Re: [time-nuts] FRK
On Tue, 27 Feb 2018 13:53:36 -0500 ewkehren via time-nuts wrote: > I have never seen a FRK or M 100 that did not have a screw iin lamp but > Attila`s unit looks like nothing I have seen before, I am not a Corby but > over time 20 units have passed through my hands My lamp is beneath the base plate, which I didn't take a photograph of, because you don't see anything but some foam that I didn't want to remove, out of fear it would just crumble in my hands. >From what I can tell, the design is close to, but not exactly as described in the FRK-L manual on Didier's site. Attila Kinali -- It is upon moral qualities that a society is ultimately founded. All the prosperity and technological sophistication in the world is of no use without that foundation. -- Miss Matheson, The Diamond Age, Neil Stephenson ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FRK
Bert OK it did look unusual. Regards On Tue, Feb 27, 2018 at 1:53 PM, ewkehren via time-nuts wrote: > PaulI have never seen a FRK or M 100 that did not have a screw iin lamp > but Attila`s unit looks like nothing I have seen before, I am not a Corby > but over time 20 units have passed through my hands > Bert > > > Sent from my Galaxy Tab® A > Original message From: paul swed > Date: 2/27/18 1:45 PM (GMT-05:00) To: Discussion of precise time and > frequency measurement Subject: Re: [time-nuts] FRK > Bert what I assume is the FRK lamp. it has a few wires and then 2 pins out > of the side. > Unless those are for mounting the lamp. > Regards > Paul > WB8TSL > > On Tue, Feb 27, 2018 at 11:21 AM, Attila Kinali wrote: > > > On Tue, 27 Feb 2018 09:01:31 -0500 > > Bob kb8tq wrote: > > > > > Judging from the date codes on some of the parts, I’d guess that > > > your FRL-L is from 1982. I’m only looking at a few parts that came > > > through well enough in the picture to read (and that have what look > > > like rational date codes …). > > > > Sorry, I didn't take much care when taking the pictures. > > I can do better ones later. > > > > But yes, the board has definitely an 80s vibe. The whole construction > > is different then what I am used to from 80s electronics, though. > > But I guess that's because it was designed and manufactured for > > hi-rel applications. > > > > Attila Kinali > > > > -- > > It is upon moral qualities that a society is ultimately founded. All > > the prosperity and technological sophistication in the world is of no > > use without that foundation. > > -- Miss Matheson, The Diamond Age, Neil Stephenson > > ___ > > time-nuts mailing list -- time-nuts@febo.com > > To unsubscribe, go to https://www.febo.com/cgi-bin/ > > mailman/listinfo/time-nuts > > and follow the instructions there. > > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/ > mailman/listinfo/time-nuts > and follow the instructions there. > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/ > mailman/listinfo/time-nuts > and follow the instructions there. > ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FRK
PaulI have never seen a FRK or M 100 that did not have a screw iin lamp but Attila`s unit looks like nothing I have seen before, I am not a Corby but over time 20 units have passed through my hands Bert Sent from my Galaxy Tab® A Original message From: paul swed Date: 2/27/18 1:45 PM (GMT-05:00) To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] FRK Bert what I assume is the FRK lamp. it has a few wires and then 2 pins out of the side. Unless those are for mounting the lamp. Regards Paul WB8TSL On Tue, Feb 27, 2018 at 11:21 AM, Attila Kinali wrote: > On Tue, 27 Feb 2018 09:01:31 -0500 > Bob kb8tq wrote: > > > Judging from the date codes on some of the parts, I’d guess that > > your FRL-L is from 1982. I’m only looking at a few parts that came > > through well enough in the picture to read (and that have what look > > like rational date codes …). > > Sorry, I didn't take much care when taking the pictures. > I can do better ones later. > > But yes, the board has definitely an 80s vibe. The whole construction > is different then what I am used to from 80s electronics, though. > But I guess that's because it was designed and manufactured for > hi-rel applications. > > Attila Kinali > > -- > It is upon moral qualities that a society is ultimately founded. All > the prosperity and technological sophistication in the world is of no > use without that foundation. > -- Miss Matheson, The Diamond Age, Neil Stephenson > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/ > mailman/listinfo/time-nuts > and follow the instructions there. > ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FRK
Bert what I assume is the FRK lamp. it has a few wires and then 2 pins out of the side. Unless those are for mounting the lamp. Regards Paul WB8TSL On Tue, Feb 27, 2018 at 11:21 AM, Attila Kinali wrote: > On Tue, 27 Feb 2018 09:01:31 -0500 > Bob kb8tq wrote: > > > Judging from the date codes on some of the parts, I’d guess that > > your FRL-L is from 1982. I’m only looking at a few parts that came > > through well enough in the picture to read (and that have what look > > like rational date codes …). > > Sorry, I didn't take much care when taking the pictures. > I can do better ones later. > > But yes, the board has definitely an 80s vibe. The whole construction > is different then what I am used to from 80s electronics, though. > But I guess that's because it was designed and manufactured for > hi-rel applications. > > Attila Kinali > > -- > It is upon moral qualities that a society is ultimately founded. All > the prosperity and technological sophistication in the world is of no > use without that foundation. > -- Miss Matheson, The Diamond Age, Neil Stephenson > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/ > mailman/listinfo/time-nuts > and follow the instructions there. > ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FRK
On Tue, 27 Feb 2018 09:01:31 -0500 Bob kb8tq wrote: > Judging from the date codes on some of the parts, I’d guess that > your FRL-L is from 1982. I’m only looking at a few parts that came > through well enough in the picture to read (and that have what look > like rational date codes …). Sorry, I didn't take much care when taking the pictures. I can do better ones later. But yes, the board has definitely an 80s vibe. The whole construction is different then what I am used to from 80s electronics, though. But I guess that's because it was designed and manufactured for hi-rel applications. Attila Kinali -- It is upon moral qualities that a society is ultimately founded. All the prosperity and technological sophistication in the world is of no use without that foundation. -- Miss Matheson, The Diamond Age, Neil Stephenson ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FRK
Which one are you talking aboutBert Kehren Sent from my Galaxy Tab® A Original message From: paul swed Date: 2/27/18 9:26 AM (GMT-05:00) To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] FRK Thanks for the pictures. Curious on the rb lamp. There seem to be 2 pins from the side. Is that a lamp start igniter? Regards Paul WB8TSL On Tue, Feb 27, 2018 at 9:01 AM, Bob kb8tq wrote: > Hi > > Judging from the date codes on some of the parts, I’d guess that > your FRL-L is from 1982. I’m only looking at a few parts that came > through well enough in the picture to read (and that have what look > like rational date codes …). > > Bob > > > On Feb 27, 2018, at 5:30 AM, Attila Kinali wrote: > > > > On Mon, 26 Feb 2018 20:04:56 -0800 > > "Tom Van Baak" wrote: > > > >> Bert's M100 Rb teardown photos are now here: > >> > >> http://leapsecond.com/bert/m100.htm > > > > For those, who would like to see the rest of M100/FRK, > > I just took pictures of my FRK-L that was sitting on my > > desk for way too long: > > > > http://time.kinali.ch/Efratom_FRK-L/ > > > > Yes, there are only the pictures of the four PCBs from outside. > > I didn't want to take the FRK further appart, as that would > > require a soldering iron, and I really should be doing something > > else. > > > > Attila Kinali > > > > -- > > It is upon moral qualities that a society is ultimately founded. All > > the prosperity and technological sophistication in the world is of no > > use without that foundation. > > -- Miss Matheson, The Diamond Age, Neil Stephenson > > ___ > > time-nuts mailing list -- time-nuts@febo.com > > To unsubscribe, go to https://www.febo.com/cgi-bin/ > mailman/listinfo/time-nuts > > and follow the instructions there. > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/ > mailman/listinfo/time-nuts > and follow the instructions there. > ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FRK
Thanks for the pictures. Curious on the rb lamp. There seem to be 2 pins from the side. Is that a lamp start igniter? Regards Paul WB8TSL On Tue, Feb 27, 2018 at 9:01 AM, Bob kb8tq wrote: > Hi > > Judging from the date codes on some of the parts, I’d guess that > your FRL-L is from 1982. I’m only looking at a few parts that came > through well enough in the picture to read (and that have what look > like rational date codes …). > > Bob > > > On Feb 27, 2018, at 5:30 AM, Attila Kinali wrote: > > > > On Mon, 26 Feb 2018 20:04:56 -0800 > > "Tom Van Baak" wrote: > > > >> Bert's M100 Rb teardown photos are now here: > >> > >> http://leapsecond.com/bert/m100.htm > > > > For those, who would like to see the rest of M100/FRK, > > I just took pictures of my FRK-L that was sitting on my > > desk for way too long: > > > > http://time.kinali.ch/Efratom_FRK-L/ > > > > Yes, there are only the pictures of the four PCBs from outside. > > I didn't want to take the FRK further appart, as that would > > require a soldering iron, and I really should be doing something > > else. > > > > Attila Kinali > > > > -- > > It is upon moral qualities that a society is ultimately founded. All > > the prosperity and technological sophistication in the world is of no > > use without that foundation. > > -- Miss Matheson, The Diamond Age, Neil Stephenson > > ___ > > time-nuts mailing list -- time-nuts@febo.com > > To unsubscribe, go to https://www.febo.com/cgi-bin/ > mailman/listinfo/time-nuts > > and follow the instructions there. > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/ > mailman/listinfo/time-nuts > and follow the instructions there. > ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FRK
Hi Judging from the date codes on some of the parts, I’d guess that your FRL-L is from 1982. I’m only looking at a few parts that came through well enough in the picture to read (and that have what look like rational date codes …). Bob > On Feb 27, 2018, at 5:30 AM, Attila Kinali wrote: > > On Mon, 26 Feb 2018 20:04:56 -0800 > "Tom Van Baak" wrote: > >> Bert's M100 Rb teardown photos are now here: >> >> http://leapsecond.com/bert/m100.htm > > For those, who would like to see the rest of M100/FRK, > I just took pictures of my FRK-L that was sitting on my > desk for way too long: > > http://time.kinali.ch/Efratom_FRK-L/ > > Yes, there are only the pictures of the four PCBs from outside. > I didn't want to take the FRK further appart, as that would > require a soldering iron, and I really should be doing something > else. > > Attila Kinali > > -- > It is upon moral qualities that a society is ultimately founded. All > the prosperity and technological sophistication in the world is of no > use without that foundation. > -- Miss Matheson, The Diamond Age, Neil Stephenson > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FRK
Thank you Tom, for the record the pictures where taken by Juerg Koegel my partner in crime Bert Kehren In a message dated 2/26/2018 11:05:19 PM Eastern Standard Time, t...@leapsecond.com writes: Bert's M100 Rb teardown photos are now here: http://leapsecond.com/bert/m100.htm /tvb - Original Message - From: "ewkehren via time-nuts" To: "Discussion of precise time and frequency measurement" Sent: Sunday, February 25, 2018 6:05 AM Subject: [time-nuts] FRK We have pictures of the guts of a M100 the file is 1.8 M off list or permission to post Bert Kehren Sent from my Galaxy Tab® A ___ ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FRK
Thank you Attila, I have seen many FRK`and M 100 but not one like yours. Some boards are very different and it is very difficult to get proper documentation.Bert Kehren Sent from my Galaxy Tab® A Original message From: Attila Kinali Date: 2/27/18 5:30 AM (GMT-05:00) To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] FRK On Mon, 26 Feb 2018 20:04:56 -0800 "Tom Van Baak" wrote: > Bert's M100 Rb teardown photos are now here: > > http://leapsecond.com/bert/m100.htm For those, who would like to see the rest of M100/FRK, I just took pictures of my FRK-L that was sitting on my desk for way too long: http://time.kinali.ch/Efratom_FRK-L/ Yes, there are only the pictures of the four PCBs from outside. I didn't want to take the FRK further appart, as that would require a soldering iron, and I really should be doing something else. Attila Kinali -- It is upon moral qualities that a society is ultimately founded. All the prosperity and technological sophistication in the world is of no use without that foundation. -- Miss Matheson, The Diamond Age, Neil Stephenson ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FRK
On Mon, 26 Feb 2018 20:04:56 -0800 "Tom Van Baak" wrote: > Bert's M100 Rb teardown photos are now here: > > http://leapsecond.com/bert/m100.htm For those, who would like to see the rest of M100/FRK, I just took pictures of my FRK-L that was sitting on my desk for way too long: http://time.kinali.ch/Efratom_FRK-L/ Yes, there are only the pictures of the four PCBs from outside. I didn't want to take the FRK further appart, as that would require a soldering iron, and I really should be doing something else. Attila Kinali -- It is upon moral qualities that a society is ultimately founded. All the prosperity and technological sophistication in the world is of no use without that foundation. -- Miss Matheson, The Diamond Age, Neil Stephenson ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FRK
Bert's M100 Rb teardown photos are now here: http://leapsecond.com/bert/m100.htm /tvb - Original Message - From: "ewkehren via time-nuts" To: "Discussion of precise time and frequency measurement" Sent: Sunday, February 25, 2018 6:05 AM Subject: [time-nuts] FRK We have pictures of the guts of a M100 the file is 1.8 M off list or permission to post Bert Kehren Sent from my Galaxy Tab® A ___ ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FRK
Thank you I am presently only on my tablet I will be on my laptop in the morning do not think that there is much interest hardware or solder iron 1%Bert Sent from my Galaxy Tab® A Original message From: Arnold Tibus Date: 2/25/18 11:04 AM (GMT-05:00) To: time-nuts@febo.com Subject: Re: [time-nuts] FRK Bert, you may upload it to this directory, which timenuts can then access and download as well, using this directory also: https://my.hidrive.com/share/5fohndsi4k The up- and downloads are much faster and there is no Mbit limit. I will keep it open for a while. Give me a note if this ok for you. Try it. Of course, from time to time I will clean up a bit. Regards, Arnold, DK2WT Am 25.02.2018 um 15:05 schrieb ewkehren via time-nuts: > We have pictures of the guts of a M100 the file is 1.8 M off list or > permission to postBert Kehren > > > Sent from my Galaxy Tab® A > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FRK
Bert, you may upload it to this directory, which timenuts can then access and download as well, using this directory also: https://my.hidrive.com/share/5fohndsi4k The up- and downloads are much faster and there is no Mbit limit. I will keep it open for a while. Give me a note if this ok for you. Try it. Of course, from time to time I will clean up a bit. Regards, Arnold, DK2WT Am 25.02.2018 um 15:05 schrieb ewkehren via time-nuts: We have pictures of the guts of a M100 the file is 1.8 M off list or permission to postBert Kehren Sent from my Galaxy Tab® A ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] FRK
We have pictures of the guts of a M100 the file is 1.8 M off list or permission to postBert Kehren Sent from my Galaxy Tab® A ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] FRK
attached a picture of the open FRK Bert Kehren___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] FRK/M100 Lamps for sale!
Hi, I have a small quantity of good used FRK/M100 lamps I am getting rid of. Offering here prior to eBay. $45.00 each which includes shipping in USA. Contact me off list. Cheers, Corby ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FRK-L Rubidium
Bob, Just wanted to let you know your advice to let the FRK run for a while was spot on. The lock voltage is down to 9.2 volts. I was able to get my thunderbolt with the bad oscillator oven working by heating the oscillator with a power resistor. After it locked I could see on an oscilloscope that it and the FRK were both exactly the same. I plan on putting the thunderbolt oscillator in an oven I'm building that will have proportional control and see how that works. Thanks for the help. Garren -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Bob Camp Sent: Saturday, February 09, 2013 10:14 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] FRK-L Rubidium Hi Let it run for a couple of days. If it's still up at > 11V, I'd tweak it down a bit. Bob On Feb 9, 2013, at 12:38 PM, Garren Davis wrote: > Found my problem with the FRK. R31 on the Osc board was burned and open. This > was caused by a shorted C16. Replaced and it is now locked. The lock voltage > is 12.7v. Is this good or should it be lower? > > Garren > > > > > On Feb 9, 2013, at 6:10 AM, "Bob Camp" wrote: > >> Hi >> >> How old is the FRK? Does it look like it's been run without a heat sink for >> very long? They tend to get flaky if run for a while (many months) without >> heat sinking. There's nothing mysterious about it. The MTBF of the parts >> gets noticeably worse as the unit heats up. >> >> Bob >> >> On Feb 9, 2013, at 1:09 AM, Garren Davis wrote: >> >>> >>> Well for some reason the 10 Mhz stopped working on the FRK. Don't know why. >>> Started up the thunderbolt. It acquired satellites but then the DAC voltage >>> went to -5 volts. It's been there for an hour. Will this change after the >>> unit stabilizes? Going to bed. Will check it tomorrow. >>> >>> Garren >>> >>> >>> >>> >>> On Feb 8, 2013, at 8:25 PM, "Ed Palmer" wrote: >>> >>>> Hi Garren, >>>> >>>> I suggest that you get the Thunderbolt working first. Without a known 10 >>>> MHz source to compare to, you're flying blind. Once the Tbolt is running, >>>> you should be able to check the frequency of the FRK by feeding both into >>>> your scope. Trigger on the Tbolt and watch what the FRK does. You should >>>> see the trace scrolling in one direction, then slow down, then stop, then >>>> scroll the other direction. The 'stop' point is at 10 MHz. The frequency >>>> sweeps a total of 20-30 Hz so it's easy to see. If you don't see the >>>> 'stop' point, the FRK isn't getting to 10 MHz. Now use the best frequency >>>> counter you've got to measure the Tbolt. Regardless of the calibration of >>>> your counter, the number your counter gives you becomes your 'new' 10 MHz. >>>> Now measure the FRK to see if it's running fast or slow. >>>> >>>> You should check the temperature of the lamp. It's easy to get at by >>>> removing the cover in the center of the heat sink. Probably best to >>>> remove the cover and then power down before you go poking around inside! >>>> The temperature of the cavity is also important, but getting to it is more >>>> of a hassle - don't go there if you don't have to. >>>> >>>> Of course, check for the normal things like internal power supply >>>> voltages, ripple, current drain (both initial and steady-state), etc. >>>> >>>> Regarding your second message, yes, the adjustment under the heat sink >>>> near the edge is the C-field. That won't help you at this point. The >>>> adjustment in the center of one side is the VCO. You could try adjusting >>>> it, but like I said, you're flying blind at this point. You won't know if >>>> you're adjusting closer to 10 MHz or further away. >>>> >>>> Good luck, >>>> >>>> Ed >>>> >>>> >>>> On 2/8/2013 6:12 PM, Garren Davis wrote: >>>>> Been lurking on the list for a while and finally started playing >>>>> with a FRK-L rubidium frequency standard. I've had this thing for >>>>> a while and decided to power it up and see what it would do. I do >>>>> not get a lock. What I see is the lamp voltage at 8.54 volts which >>>>> I
Re: [time-nuts] FRK-L Rubidium
It is possible to open the can if you are careful. A good vacuum desoldering tool is a good start to remove as much of the solder as possible. Then one would peal the can open a bit at a time. Then you need to find out where the failure is. But to answer your question, yes just buy one, it's much easier. But first check that there is power to the heater. - Original Message - From: "Garren Davis" To: "Discussion of precise time and frequency measurement" Sent: Monday, February 11, 2013 12:01 PM Subject: Re: [time-nuts] FRK-L Rubidium Ed, Bob, This morning I noticed the crystal control voltage was down to 11 volts. I'll let it keep running to see if it drops any further. The tuning capacitor is adjusted out about as far as I want to set it. Any further and I think the adjustment screw will fall out. I did remove C11 as an experiment to see what it would do to the frequency. It dropped a lot so now I know I can put a smaller one in if I need more adjustment. Next up is the Tbolt. I'm pretty sure the oven heater is not working. Has anyone taken apart the trimble oscillator? It looks like it's sealed pretty good. I see quite a few for sale. Is it just easier to replace it? Thanks for all the help. Garren -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Ed Palmer Sent: Sunday, February 10, 2013 11:02 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] FRK-L Rubidium Hi Garren, Yes, you're right. Silly me, I made the mistake of believing what was written in the manual which says 2-12 volts. When I measure it, I see ~2-16 volts. Let that be a warning to you. This isn't the first time that manual has led me astray! I should have known better. Did you notice that the voltage changes as you adjust the capacitor on the side? If the adjustment is at it's limit, you may have to change capacitors A3C11 and maybe A3C12 to get the oscillator back on frequency. It's explained in the manual. :-) Let it settle for at least a few days and see which direction the crystal control voltage moves. If it falls you're fine. If it rises higher, you may want to look at the capacitors. If you have to change the capacitors, be sure to use NP0/C0G type capacitors. Bob's comments regarding the C-field are right on the money. It's for fine tuning after you have a stable lock. It won't help you obtain or maintain a lock. You won't be able to adjust it without a known, stable 10 MHz reference source like the Tbolt and some good measurement equipment. Ed On 2/10/2013 9:27 AM, Garren Davis wrote: Hi Ed, The voltage swings from 2v to 17v. Doesn't that mean I have about 4 to 5 volt margin if it's locked at 12 volts? I had to adjust the capacitor out almost all the way to get it to lock. If I need to adjust it more can I use the C-field adjustment or should I stay away from that? Garren On Feb 9, 2013, at 10:48 PM, "Ed Palmer" wrote: Hi Garren, Congrats on your repair. Since the crystal control voltage is spec'd as ~1 to 12 Vdc, you're apparently holding onto lock by the narrowest of margins. You definitely want to adjust the oscillator to bring that voltage closer to the middle of it's range. Ed On 2/9/2013 11:38 AM, Garren Davis wrote: Found my problem with the FRK. R31 on the Osc board was burned and open. This was caused by a shorted C16. Replaced and it is now locked. The lock voltage is 12.7v. Is this good or should it be lower? Garren On Feb 9, 2013, at 6:10 AM, "Bob Camp" wrote: Hi How old is the FRK? Does it look like it's been run without a heat sink for very long? They tend to get flaky if run for a while (many months) without heat sinking. There's nothing mysterious about it. The MTBF of the parts gets noticeably worse as the unit heats up. Bob On Feb 9, 2013, at 1:09 AM, Garren Davis wrote: Well for some reason the 10 Mhz stopped working on the FRK. Don't know why. Started up the thunderbolt. It acquired satellites but then the DAC voltage went to -5 volts. It's been there for an hour. Will this change after the unit stabilizes? Going to bed. Will check it tomorrow. Garren On Feb 8, 2013, at 8:25 PM, "Ed Palmer" wrote: Hi Garren, I suggest that you get the Thunderbolt working first. Without a known 10 MHz source to compare to, you're flying blind. Once the Tbolt is running, you should be able to check the frequency of the FRK by feeding both into your scope. Trigger on the Tbolt and watch what the FRK does. You should see the trace scrolling in one direction, then slow down, then stop, then scroll the other direction. The 'stop' point is at 10 MHz. The frequency sweeps a total of 20-30 Hz so it's easy to see. If you don't
Re: [time-nuts] FRK-L Rubidium
Ed, Bob, This morning I noticed the crystal control voltage was down to 11 volts. I'll let it keep running to see if it drops any further. The tuning capacitor is adjusted out about as far as I want to set it. Any further and I think the adjustment screw will fall out. I did remove C11 as an experiment to see what it would do to the frequency. It dropped a lot so now I know I can put a smaller one in if I need more adjustment. Next up is the Tbolt. I'm pretty sure the oven heater is not working. Has anyone taken apart the trimble oscillator? It looks like it's sealed pretty good. I see quite a few for sale. Is it just easier to replace it? Thanks for all the help. Garren -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Ed Palmer Sent: Sunday, February 10, 2013 11:02 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] FRK-L Rubidium Hi Garren, Yes, you're right. Silly me, I made the mistake of believing what was written in the manual which says 2-12 volts. When I measure it, I see ~2-16 volts. Let that be a warning to you. This isn't the first time that manual has led me astray! I should have known better. Did you notice that the voltage changes as you adjust the capacitor on the side? If the adjustment is at it's limit, you may have to change capacitors A3C11 and maybe A3C12 to get the oscillator back on frequency. It's explained in the manual. :-) Let it settle for at least a few days and see which direction the crystal control voltage moves. If it falls you're fine. If it rises higher, you may want to look at the capacitors. If you have to change the capacitors, be sure to use NP0/C0G type capacitors. Bob's comments regarding the C-field are right on the money. It's for fine tuning after you have a stable lock. It won't help you obtain or maintain a lock. You won't be able to adjust it without a known, stable 10 MHz reference source like the Tbolt and some good measurement equipment. Ed On 2/10/2013 9:27 AM, Garren Davis wrote: > Hi Ed, > > The voltage swings from 2v to 17v. Doesn't that mean I have about 4 to 5 volt > margin if it's locked at 12 volts? > > I had to adjust the capacitor out almost all the way to get it to lock. If I > need to adjust it more can I use the C-field adjustment or should I stay away > from that? > > Garren > > > On Feb 9, 2013, at 10:48 PM, "Ed Palmer" wrote: > >> Hi Garren, >> >> Congrats on your repair. Since the crystal control voltage is spec'd as ~1 >> to 12 Vdc, you're apparently holding onto lock by the narrowest of margins. >> You definitely want to adjust the oscillator to bring that voltage closer to >> the middle of it's range. >> >> Ed >> >> On 2/9/2013 11:38 AM, Garren Davis wrote: >>> Found my problem with the FRK. R31 on the Osc board was burned and open. >>> This was caused by a shorted C16. Replaced and it is now locked. The lock >>> voltage is 12.7v. Is this good or should it be lower? >>> >>> Garren >>> >>> On Feb 9, 2013, at 6:10 AM, "Bob Camp" wrote: >>> >>>> Hi >>>> >>>> How old is the FRK? Does it look like it's been run without a heat sink >>>> for very long? They tend to get flaky if run for a while (many months) >>>> without heat sinking. There's nothing mysterious about it. The MTBF of the >>>> parts gets noticeably worse as the unit heats up. >>>> >>>> Bob >>>> >>>> On Feb 9, 2013, at 1:09 AM, Garren Davis wrote: >>>> >>>>> Well for some reason the 10 Mhz stopped working on the FRK. Don't know >>>>> why. Started up the thunderbolt. It acquired satellites but then the DAC >>>>> voltage went to -5 volts. It's been there for an hour. Will this change >>>>> after the unit stabilizes? Going to bed. Will check it tomorrow. >>>>> >>>>> Garren >>>>> >>>>> >>>>> On Feb 8, 2013, at 8:25 PM, "Ed Palmer" wrote: >>>>> >>>>>> Hi Garren, >>>>>> >>>>>> I suggest that you get the Thunderbolt working first. Without a known >>>>>> 10 MHz source to compare to, you're flying blind. Once the Tbolt is >>>>>> running, you should be able to check the frequency of the FRK by feeding >>>>>> both into your scope. Trigger on the Tbolt and watch what the FRK does. >>>>>> You should see the trace scrolling i
Re: [time-nuts] FRK-L Rubidium
Hi Garren, Yes, you're right. Silly me, I made the mistake of believing what was written in the manual which says 2-12 volts. When I measure it, I see ~2-16 volts. Let that be a warning to you. This isn't the first time that manual has led me astray! I should have known better. Did you notice that the voltage changes as you adjust the capacitor on the side? If the adjustment is at it's limit, you may have to change capacitors A3C11 and maybe A3C12 to get the oscillator back on frequency. It's explained in the manual. :-) Let it settle for at least a few days and see which direction the crystal control voltage moves. If it falls you're fine. If it rises higher, you may want to look at the capacitors. If you have to change the capacitors, be sure to use NP0/C0G type capacitors. Bob's comments regarding the C-field are right on the money. It's for fine tuning after you have a stable lock. It won't help you obtain or maintain a lock. You won't be able to adjust it without a known, stable 10 MHz reference source like the Tbolt and some good measurement equipment. Ed On 2/10/2013 9:27 AM, Garren Davis wrote: Hi Ed, The voltage swings from 2v to 17v. Doesn't that mean I have about 4 to 5 volt margin if it's locked at 12 volts? I had to adjust the capacitor out almost all the way to get it to lock. If I need to adjust it more can I use the C-field adjustment or should I stay away from that? Garren On Feb 9, 2013, at 10:48 PM, "Ed Palmer" wrote: Hi Garren, Congrats on your repair. Since the crystal control voltage is spec'd as ~1 to 12 Vdc, you're apparently holding onto lock by the narrowest of margins. You definitely want to adjust the oscillator to bring that voltage closer to the middle of it's range. Ed On 2/9/2013 11:38 AM, Garren Davis wrote: Found my problem with the FRK. R31 on the Osc board was burned and open. This was caused by a shorted C16. Replaced and it is now locked. The lock voltage is 12.7v. Is this good or should it be lower? Garren On Feb 9, 2013, at 6:10 AM, "Bob Camp" wrote: Hi How old is the FRK? Does it look like it's been run without a heat sink for very long? They tend to get flaky if run for a while (many months) without heat sinking. There's nothing mysterious about it. The MTBF of the parts gets noticeably worse as the unit heats up. Bob On Feb 9, 2013, at 1:09 AM, Garren Davis wrote: Well for some reason the 10 Mhz stopped working on the FRK. Don't know why. Started up the thunderbolt. It acquired satellites but then the DAC voltage went to -5 volts. It's been there for an hour. Will this change after the unit stabilizes? Going to bed. Will check it tomorrow. Garren On Feb 8, 2013, at 8:25 PM, "Ed Palmer" wrote: Hi Garren, I suggest that you get the Thunderbolt working first. Without a known 10 MHz source to compare to, you're flying blind. Once the Tbolt is running, you should be able to check the frequency of the FRK by feeding both into your scope. Trigger on the Tbolt and watch what the FRK does. You should see the trace scrolling in one direction, then slow down, then stop, then scroll the other direction. The 'stop' point is at 10 MHz. The frequency sweeps a total of 20-30 Hz so it's easy to see. If you don't see the 'stop' point, the FRK isn't getting to 10 MHz. Now use the best frequency counter you've got to measure the Tbolt. Regardless of the calibration of your counter, the number your counter gives you becomes your 'new' 10 MHz. Now measure the FRK to see if it's running fast or slow. You should check the temperature of the lamp. It's easy to get at by removing the cover in the center of the heat sink. Probably best to remove the cover and then power down before you go poking around inside! The temperature of the cavity is also important, but getting to it is more of a hassle - don't go there if you don't have to. Of course, check for the normal things like internal power supply voltages, ripple, current drain (both initial and steady-state), etc. Regarding your second message, yes, the adjustment under the heat sink near the edge is the C-field. That won't help you at this point. The adjustment in the center of one side is the VCO. You could try adjusting it, but like I said, you're flying blind at this point. You won't know if you're adjusting closer to 10 MHz or further away. Good luck, Ed On 2/8/2013 6:12 PM, Garren Davis wrote: Been lurking on the list for a while and finally started playing with a FRK-L rubidium frequency standard. I've had this thing for a while and decided to power it up and see what it would do. I do not get a lock. What I see is the lamp voltage at 8.54 volts which I think is good but the xtal control voltage swings from 2 volts to 15 volts and back to 2 volts and keeps cycling like that. I don't have a good frequency counter but I have a 3 Ghz 40 G/sample scope and it shows that the 10 MHz signal is there. I jus
Re: [time-nuts] FRK-L Rubidium
Hi The OCVCXO tuning voltage adjust on the 10 MHz simply centers up the sweep process. It has no impact on the output frequency once the unit is locked up. The C field adjustment sets the Rb on frequency once it is locked. It is only used to set the unit on frequency. Since the range on the C field is maybe 0.002 ppm and the 10 MHz set is maybe 1 ppm, there is little the C field would do to "help" the 10 MHz adjust. It is quite possible for the crystal in the 10 MHz oscillator to age further than tuning range on the oscillator. You can either replace the crystal (good luck) or fiddle one of the fixed caps in the oscillator circuit (normally much easier). Bob On Feb 10, 2013, at 10:27 AM, Garren Davis wrote: > > Hi Ed, > > The voltage swings from 2v to 17v. Doesn't that mean I have about 4 to 5 volt > margin if it's locked at 12 volts? > > I had to adjust the capacitor out almost all the way to get it to lock. If I > need to adjust it more can I use the C-field adjustment or should I stay away > from that? > > Garren > > > > > On Feb 9, 2013, at 10:48 PM, "Ed Palmer" wrote: > >> Hi Garren, >> >> Congrats on your repair. Since the crystal control voltage is spec'd as ~1 >> to 12 Vdc, you're apparently holding onto lock by the narrowest of margins. >> You definitely want to adjust the oscillator to bring that voltage closer to >> the middle of it's range. >> >> Ed >> >> On 2/9/2013 11:38 AM, Garren Davis wrote: >>> Found my problem with the FRK. R31 on the Osc board was burned and open. >>> This was caused by a shorted C16. Replaced and it is now locked. The lock >>> voltage is 12.7v. Is this good or should it be lower? >>> >>> Garren >>> >>> On Feb 9, 2013, at 6:10 AM, "Bob Camp" wrote: >>> Hi How old is the FRK? Does it look like it's been run without a heat sink for very long? They tend to get flaky if run for a while (many months) without heat sinking. There's nothing mysterious about it. The MTBF of the parts gets noticeably worse as the unit heats up. Bob On Feb 9, 2013, at 1:09 AM, Garren Davis wrote: > Well for some reason the 10 Mhz stopped working on the FRK. Don't know > why. Started up the thunderbolt. It acquired satellites but then the DAC > voltage went to -5 volts. It's been there for an hour. Will this change > after the unit stabilizes? Going to bed. Will check it tomorrow. > > Garren > > > On Feb 8, 2013, at 8:25 PM, "Ed Palmer" wrote: > >> Hi Garren, >> >> I suggest that you get the Thunderbolt working first. Without a known >> 10 MHz source to compare to, you're flying blind. Once the Tbolt is >> running, you should be able to check the frequency of the FRK by feeding >> both into your scope. Trigger on the Tbolt and watch what the FRK does. >> You should see the trace scrolling in one direction, then slow down, >> then stop, then scroll the other direction. The 'stop' point is at 10 >> MHz. The frequency sweeps a total of 20-30 Hz so it's easy to see. If >> you don't see the 'stop' point, the FRK isn't getting to 10 MHz. Now >> use the best frequency counter you've got to measure the Tbolt. >> Regardless of the calibration of your counter, the number your counter >> gives you becomes your 'new' 10 MHz. Now measure the FRK to see if it's >> running fast or slow. >> >> You should check the temperature of the lamp. It's easy to get at by >> removing the cover in the center of the heat sink. Probably best to >> remove the cover and then power down before you go poking around inside! >> The temperature of the cavity is also important, but getting to it is >> more of a hassle - don't go there if you don't have to. >> >> Of course, check for the normal things like internal power supply >> voltages, ripple, current drain (both initial and steady-state), etc. >> >> Regarding your second message, yes, the adjustment under the heat sink >> near the edge is the C-field. That won't help you at this point. The >> adjustment in the center of one side is the VCO. You could try >> adjusting it, but like I said, you're flying blind at this point. You >> won't know if you're adjusting closer to 10 MHz or further away. >> >> Good luck, >> >> Ed >> >> >> On 2/8/2013 6:12 PM, Garren Davis wrote: >>> Been lurking on the list for a while and finally started playing with a >>> FRK-L rubidium frequency standard. I've had this thing for a while and >>> decided to power it up and see what it would do. I do not get a lock. >>> What I see is the lamp voltage at 8.54 volts which I think is good but >>> the xtal control voltage swings from 2 volts to 15 volts and back to 2 >>> volts and keeps cycling like that. I don't have a good frequency >>>
Re: [time-nuts] FRK-L Rubidium
Bob, That was my thoughts also. The GPS receiver and serial connection to the computer are working so I know the power connections are ok. I think I bought this through a group buy from someone on this list and they said all were tested before they were shipped. Maybe it was just time for the heater to fail. Are these trimbles repairable or is it easier to just replace these? Garren On Feb 9, 2013, at 8:14 AM, "Bob Camp" wrote: > Hi > > The +12 V supply at 60 ma likely means that the heater in the OCXO is not > working. If you have 60 ma on the -12 V supply, it's pulling about 10X more > than it should. > > Bob > > On Feb 9, 2013, at 10:01 AM, Garren Davis wrote: > >> Thanks for the reply. >> I found that the 12v current is only 60ma. I suppose that means the Osc. >> heater is not working. I'm not having much luck with this time nuts stuff. >> First the FRK and now the thunderbolt. Guess I'll start looking for another >> one. >> >> Garren >> >> >> >> >> On Feb 9, 2013, at 6:01 AM, "Bob Camp" wrote: >> >>> Hi >>> >>> DAC clamped at -5 volts suggests that the TBolt has issues. First thing to >>> check is the -12 volt supply. If it's missing, the DAC will indicate -5 on >>> the screen and be sitting at 0 in real life. There are a couple other >>> things in the DAC circuit that can make it malfunction. >>> >>> Bob >>> >>> On Feb 9, 2013, at 1:09 AM, Garren Davis wrote: >>> Well for some reason the 10 Mhz stopped working on the FRK. Don't know why. Started up the thunderbolt. It acquired satellites but then the DAC voltage went to -5 volts. It's been there for an hour. Will this change after the unit stabilizes? Going to bed. Will check it tomorrow. Garren On Feb 8, 2013, at 8:25 PM, "Ed Palmer" wrote: > Hi Garren, > > I suggest that you get the Thunderbolt working first. Without a known 10 > MHz source to compare to, you're flying blind. Once the Tbolt is > running, you should be able to check the frequency of the FRK by feeding > both into your scope. Trigger on the Tbolt and watch what the FRK does. > You should see the trace scrolling in one direction, then slow down, then > stop, then scroll the other direction. The 'stop' point is at 10 MHz. > The frequency sweeps a total of 20-30 Hz so it's easy to see. If you > don't see the 'stop' point, the FRK isn't getting to 10 MHz. Now use the > best frequency counter you've got to measure the Tbolt. Regardless of > the calibration of your counter, the number your counter gives you > becomes your 'new' 10 MHz. Now measure the FRK to see if it's running > fast or slow. > > You should check the temperature of the lamp. It's easy to get at by > removing the cover in the center of the heat sink. Probably best to > remove the cover and then power down before you go poking around inside! > The temperature of the cavity is also important, but getting to it is > more of a hassle - don't go there if you don't have to. > > Of course, check for the normal things like internal power supply > voltages, ripple, current drain (both initial and steady-state), etc. > > Regarding your second message, yes, the adjustment under the heat sink > near the edge is the C-field. That won't help you at this point. The > adjustment in the center of one side is the VCO. You could try adjusting > it, but like I said, you're flying blind at this point. You won't know > if you're adjusting closer to 10 MHz or further away. > > Good luck, > > Ed > > > On 2/8/2013 6:12 PM, Garren Davis wrote: >> Been lurking on the list for a while and finally started playing with a >> FRK-L rubidium frequency standard. I've had this thing for a while and >> decided to power it up and see what it would do. I do not get a lock. >> What I see is the lamp voltage at 8.54 volts which I think is good but >> the xtal control voltage swings from 2 volts to 15 volts and back to 2 >> volts and keeps cycling like that. I don't have a good frequency counter >> but I have a 3 Ghz 40 G/sample scope and it shows that the 10 MHz signal >> is there. I just don't know how accurate it is. Has anyone seen a >> problem like this? Can anyone point me to a place to start debugging >> this? I have the schematics and test tools. I am a test engineer so I'm >> not afraid to poke around in the guts of this thing. Hopefully I can get >> this thing running. I also have a thunderbolt that I'll get running this >> weekend. I don't know how deep I'll get into this time-nuts thing but I >> have this nice scope and a Wavecrest sitting in my garage > >> a >>> n d > I'd lik > e to put them to use. Any help would be appreciated. >> >> Garren > > __
Re: [time-nuts] FRK-L Rubidium
Hi Ed, The voltage swings from 2v to 17v. Doesn't that mean I have about 4 to 5 volt margin if it's locked at 12 volts? I had to adjust the capacitor out almost all the way to get it to lock. If I need to adjust it more can I use the C-field adjustment or should I stay away from that? Garren On Feb 9, 2013, at 10:48 PM, "Ed Palmer" wrote: > Hi Garren, > > Congrats on your repair. Since the crystal control voltage is spec'd as ~1 > to 12 Vdc, you're apparently holding onto lock by the narrowest of margins. > You definitely want to adjust the oscillator to bring that voltage closer to > the middle of it's range. > > Ed > > On 2/9/2013 11:38 AM, Garren Davis wrote: >> Found my problem with the FRK. R31 on the Osc board was burned and open. >> This was caused by a shorted C16. Replaced and it is now locked. The lock >> voltage is 12.7v. Is this good or should it be lower? >> >> Garren >> >> On Feb 9, 2013, at 6:10 AM, "Bob Camp" wrote: >> >>> Hi >>> >>> How old is the FRK? Does it look like it's been run without a heat sink for >>> very long? They tend to get flaky if run for a while (many months) without >>> heat sinking. There's nothing mysterious about it. The MTBF of the parts >>> gets noticeably worse as the unit heats up. >>> >>> Bob >>> >>> On Feb 9, 2013, at 1:09 AM, Garren Davis wrote: >>> Well for some reason the 10 Mhz stopped working on the FRK. Don't know why. Started up the thunderbolt. It acquired satellites but then the DAC voltage went to -5 volts. It's been there for an hour. Will this change after the unit stabilizes? Going to bed. Will check it tomorrow. Garren On Feb 8, 2013, at 8:25 PM, "Ed Palmer" wrote: > Hi Garren, > > I suggest that you get the Thunderbolt working first. Without a known 10 > MHz source to compare to, you're flying blind. Once the Tbolt is > running, you should be able to check the frequency of the FRK by feeding > both into your scope. Trigger on the Tbolt and watch what the FRK does. > You should see the trace scrolling in one direction, then slow down, then > stop, then scroll the other direction. The 'stop' point is at 10 MHz. > The frequency sweeps a total of 20-30 Hz so it's easy to see. If you > don't see the 'stop' point, the FRK isn't getting to 10 MHz. Now use the > best frequency counter you've got to measure the Tbolt. Regardless of > the calibration of your counter, the number your counter gives you > becomes your 'new' 10 MHz. Now measure the FRK to see if it's running > fast or slow. > > You should check the temperature of the lamp. It's easy to get at by > removing the cover in the center of the heat sink. Probably best to > remove the cover and then power down before you go poking around inside! > The temperature of the cavity is also important, but getting to it is > more of a hassle - don't go there if you don't have to. > > Of course, check for the normal things like internal power supply > voltages, ripple, current drain (both initial and steady-state), etc. > > Regarding your second message, yes, the adjustment under the heat sink > near the edge is the C-field. That won't help you at this point. The > adjustment in the center of one side is the VCO. You could try adjusting > it, but like I said, you're flying blind at this point. You won't know > if you're adjusting closer to 10 MHz or further away. > > Good luck, > > Ed > > > On 2/8/2013 6:12 PM, Garren Davis wrote: >> Been lurking on the list for a while and finally started playing with a >> FRK-L rubidium frequency standard. I've had this thing for a while and >> decided to power it up and see what it would do. I do not get a lock. >> What I see is the lamp voltage at 8.54 volts which I think is good but >> the xtal control voltage swings from 2 volts to 15 volts and back to 2 >> volts and keeps cycling like that. I don't have a good frequency counter >> but I have a 3 Ghz 40 G/sample scope and it shows that the 10 MHz signal >> is there. I just don't know how accurate it is. Has anyone seen a >> problem like this? Can anyone point me to a place to start debugging >> this? I have the schematics and test tools. I am a test engineer so I'm >> not afraid to poke around in the guts of this thing. Hopefully I can get >> this thing running. I also have a thunderbolt that I'll get running this >> weekend. I don't know how deep I'll get into this time-nuts thing but I >> have this nice scope and a Wavecrest sitting in my garage > and I'd > like to put them to use. Any help would be appreciated. >> Garren > > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listin
Re: [time-nuts] FRK-L Rubidium
Hi Garren, Congrats on your repair. Since the crystal control voltage is spec'd as ~1 to 12 Vdc, you're apparently holding onto lock by the narrowest of margins. You definitely want to adjust the oscillator to bring that voltage closer to the middle of it's range. Ed On 2/9/2013 11:38 AM, Garren Davis wrote: Found my problem with the FRK. R31 on the Osc board was burned and open. This was caused by a shorted C16. Replaced and it is now locked. The lock voltage is 12.7v. Is this good or should it be lower? Garren On Feb 9, 2013, at 6:10 AM, "Bob Camp" wrote: Hi How old is the FRK? Does it look like it's been run without a heat sink for very long? They tend to get flaky if run for a while (many months) without heat sinking. There's nothing mysterious about it. The MTBF of the parts gets noticeably worse as the unit heats up. Bob On Feb 9, 2013, at 1:09 AM, Garren Davis wrote: Well for some reason the 10 Mhz stopped working on the FRK. Don't know why. Started up the thunderbolt. It acquired satellites but then the DAC voltage went to -5 volts. It's been there for an hour. Will this change after the unit stabilizes? Going to bed. Will check it tomorrow. Garren On Feb 8, 2013, at 8:25 PM, "Ed Palmer" wrote: Hi Garren, I suggest that you get the Thunderbolt working first. Without a known 10 MHz source to compare to, you're flying blind. Once the Tbolt is running, you should be able to check the frequency of the FRK by feeding both into your scope. Trigger on the Tbolt and watch what the FRK does. You should see the trace scrolling in one direction, then slow down, then stop, then scroll the other direction. The 'stop' point is at 10 MHz. The frequency sweeps a total of 20-30 Hz so it's easy to see. If you don't see the 'stop' point, the FRK isn't getting to 10 MHz. Now use the best frequency counter you've got to measure the Tbolt. Regardless of the calibration of your counter, the number your counter gives you becomes your 'new' 10 MHz. Now measure the FRK to see if it's running fast or slow. You should check the temperature of the lamp. It's easy to get at by removing the cover in the center of the heat sink. Probably best to remove the cover and then power down before you go poking around inside! The temperature of the cavity is also important, but getting to it is more of a hassle - don't go there if you don't have to. Of course, check for the normal things like internal power supply voltages, ripple, current drain (both initial and steady-state), etc. Regarding your second message, yes, the adjustment under the heat sink near the edge is the C-field. That won't help you at this point. The adjustment in the center of one side is the VCO. You could try adjusting it, but like I said, you're flying blind at this point. You won't know if you're adjusting closer to 10 MHz or further away. Good luck, Ed On 2/8/2013 6:12 PM, Garren Davis wrote: Been lurking on the list for a while and finally started playing with a FRK-L rubidium frequency standard. I've had this thing for a while and decided to power it up and see what it would do. I do not get a lock. What I see is the lamp voltage at 8.54 volts which I think is good but the xtal control voltage swings from 2 volts to 15 volts and back to 2 volts and keeps cycling like that. I don't have a good frequency counter but I have a 3 Ghz 40 G/sample scope and it shows that the 10 MHz signal is there. I just don't know how accurate it is. Has anyone seen a problem like this? Can anyone point me to a place to start debugging this? I have the schematics and test tools. I am a test engineer so I'm not afraid to poke around in the guts of this thing. Hopefully I can get this thing running. I also have a thunderbolt that I'll get running this weekend. I don't know how deep I'll get into this time-nuts thing but I have this nice scope and a Wavecrest sitting in my garage and I'd like to put them to use. Any help would be appreciated. Garren ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FRK-L Rubidium
I'll add my own FRK-L failure story. I have a FRK that suddenly stopped locking. The 10 MHz was there, but off frequency so much that I couldn't adjust it to sweep over 10 MHz. It suddenly occurred to me that the crystal oven housing should be hotter than just barely warm to the touch (it's usually too hot to touch). I found that the Darlington transistor that is used as a oven heater was bad. Replacing the transistor fixed the problem. Tom --- On Sat, 2/9/13, Dan Rae wrote: From: Dan Rae Subject: Re: [time-nuts] FRK-L Rubidium To: "Discussion of precise time and frequency measurement" Date: Saturday, February 9, 2013, 10:31 AM Since we're offering up faults for the FRK, I'll add one that I've found: there's a CMOS 4060 oscillator that should go off at 8.128 kHz, set by an adjust on test R. If this drifts off enough the lock will never happen. It provides the FM frequency for the synth. Dan ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FRK-L Rubidium
Since we're offering up faults for the FRK, I'll add one that I've found: there's a CMOS 4060 oscillator that should go off at 8.128 kHz, set by an adjust on test R. If this drifts off enough the lock will never happen. It provides the FM frequency for the synth. Dan ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FRK-L Rubidium
Hi Let it run for a couple of days. If it's still up at > 11V, I'd tweak it down a bit. Bob On Feb 9, 2013, at 12:38 PM, Garren Davis wrote: > Found my problem with the FRK. R31 on the Osc board was burned and open. This > was caused by a shorted C16. Replaced and it is now locked. The lock voltage > is 12.7v. Is this good or should it be lower? > > Garren > > > > > On Feb 9, 2013, at 6:10 AM, "Bob Camp" wrote: > >> Hi >> >> How old is the FRK? Does it look like it's been run without a heat sink for >> very long? They tend to get flaky if run for a while (many months) without >> heat sinking. There's nothing mysterious about it. The MTBF of the parts >> gets noticeably worse as the unit heats up. >> >> Bob >> >> On Feb 9, 2013, at 1:09 AM, Garren Davis wrote: >> >>> >>> Well for some reason the 10 Mhz stopped working on the FRK. Don't know why. >>> Started up the thunderbolt. It acquired satellites but then the DAC voltage >>> went to -5 volts. It's been there for an hour. Will this change after the >>> unit stabilizes? Going to bed. Will check it tomorrow. >>> >>> Garren >>> >>> >>> >>> >>> On Feb 8, 2013, at 8:25 PM, "Ed Palmer" wrote: >>> Hi Garren, I suggest that you get the Thunderbolt working first. Without a known 10 MHz source to compare to, you're flying blind. Once the Tbolt is running, you should be able to check the frequency of the FRK by feeding both into your scope. Trigger on the Tbolt and watch what the FRK does. You should see the trace scrolling in one direction, then slow down, then stop, then scroll the other direction. The 'stop' point is at 10 MHz. The frequency sweeps a total of 20-30 Hz so it's easy to see. If you don't see the 'stop' point, the FRK isn't getting to 10 MHz. Now use the best frequency counter you've got to measure the Tbolt. Regardless of the calibration of your counter, the number your counter gives you becomes your 'new' 10 MHz. Now measure the FRK to see if it's running fast or slow. You should check the temperature of the lamp. It's easy to get at by removing the cover in the center of the heat sink. Probably best to remove the cover and then power down before you go poking around inside! The temperature of the cavity is also important, but getting to it is more of a hassle - don't go there if you don't have to. Of course, check for the normal things like internal power supply voltages, ripple, current drain (both initial and steady-state), etc. Regarding your second message, yes, the adjustment under the heat sink near the edge is the C-field. That won't help you at this point. The adjustment in the center of one side is the VCO. You could try adjusting it, but like I said, you're flying blind at this point. You won't know if you're adjusting closer to 10 MHz or further away. Good luck, Ed On 2/8/2013 6:12 PM, Garren Davis wrote: > Been lurking on the list for a while and finally started playing with a > FRK-L rubidium frequency standard. I've had this thing for a while and > decided to power it up and see what it would do. I do not get a lock. > What I see is the lamp voltage at 8.54 volts which I think is good but > the xtal control voltage swings from 2 volts to 15 volts and back to 2 > volts and keeps cycling like that. I don't have a good frequency counter > but I have a 3 Ghz 40 G/sample scope and it shows that the 10 MHz signal > is there. I just don't know how accurate it is. Has anyone seen a problem > like this? Can anyone point me to a place to start debugging this? I have > the schematics and test tools. I am a test engineer so I'm not afraid to > poke around in the guts of this thing. Hopefully I can get this thing > running. I also have a thunderbolt that I'll get running this weekend. I > don't know how deep I'll get into this time-nuts thing but I have this > nice scope and a Wavecrest sitting in my garage > a >> n >>> d I'd lik e to put them to use. Any help would be appreciated. > > Garren ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. >>> >>> >>> >>> This message and any attached documents contain information from QLogic >>> Corporation or its wholly-owned subsidiaries that may be confidential. If >>> you are not the intended recipient, you may not read, copy, distribute, or >>> use this information. If you have received this transmission in error, >>> please notify the sender immediately by reply e-mail and then delete this >>> message. >>> >>> __
Re: [time-nuts] FRK-L Rubidium
Found my problem with the FRK. R31 on the Osc board was burned and open. This was caused by a shorted C16. Replaced and it is now locked. The lock voltage is 12.7v. Is this good or should it be lower? Garren On Feb 9, 2013, at 6:10 AM, "Bob Camp" wrote: > Hi > > How old is the FRK? Does it look like it's been run without a heat sink for > very long? They tend to get flaky if run for a while (many months) without > heat sinking. There's nothing mysterious about it. The MTBF of the parts gets > noticeably worse as the unit heats up. > > Bob > > On Feb 9, 2013, at 1:09 AM, Garren Davis wrote: > >> >> Well for some reason the 10 Mhz stopped working on the FRK. Don't know why. >> Started up the thunderbolt. It acquired satellites but then the DAC voltage >> went to -5 volts. It's been there for an hour. Will this change after the >> unit stabilizes? Going to bed. Will check it tomorrow. >> >> Garren >> >> >> >> >> On Feb 8, 2013, at 8:25 PM, "Ed Palmer" wrote: >> >>> Hi Garren, >>> >>> I suggest that you get the Thunderbolt working first. Without a known 10 >>> MHz source to compare to, you're flying blind. Once the Tbolt is running, >>> you should be able to check the frequency of the FRK by feeding both into >>> your scope. Trigger on the Tbolt and watch what the FRK does. You should >>> see the trace scrolling in one direction, then slow down, then stop, then >>> scroll the other direction. The 'stop' point is at 10 MHz. The frequency >>> sweeps a total of 20-30 Hz so it's easy to see. If you don't see the >>> 'stop' point, the FRK isn't getting to 10 MHz. Now use the best frequency >>> counter you've got to measure the Tbolt. Regardless of the calibration of >>> your counter, the number your counter gives you becomes your 'new' 10 MHz. >>> Now measure the FRK to see if it's running fast or slow. >>> >>> You should check the temperature of the lamp. It's easy to get at by >>> removing the cover in the center of the heat sink. Probably best to remove >>> the cover and then power down before you go poking around inside! The >>> temperature of the cavity is also important, but getting to it is more of a >>> hassle - don't go there if you don't have to. >>> >>> Of course, check for the normal things like internal power supply voltages, >>> ripple, current drain (both initial and steady-state), etc. >>> >>> Regarding your second message, yes, the adjustment under the heat sink near >>> the edge is the C-field. That won't help you at this point. The >>> adjustment in the center of one side is the VCO. You could try adjusting >>> it, but like I said, you're flying blind at this point. You won't know if >>> you're adjusting closer to 10 MHz or further away. >>> >>> Good luck, >>> >>> Ed >>> >>> >>> On 2/8/2013 6:12 PM, Garren Davis wrote: Been lurking on the list for a while and finally started playing with a FRK-L rubidium frequency standard. I've had this thing for a while and decided to power it up and see what it would do. I do not get a lock. What I see is the lamp voltage at 8.54 volts which I think is good but the xtal control voltage swings from 2 volts to 15 volts and back to 2 volts and keeps cycling like that. I don't have a good frequency counter but I have a 3 Ghz 40 G/sample scope and it shows that the 10 MHz signal is there. I just don't know how accurate it is. Has anyone seen a problem like this? Can anyone point me to a place to start debugging this? I have the schematics and test tools. I am a test engineer so I'm not afraid to poke around in the guts of this thing. Hopefully I can get this thing running. I also have a thunderbolt that I'll get running this weekend. I don't know how deep I'll get into this time-nuts thing but I have this nice scope and a Wavecrest sitting in my garage a > n >> d >>> I'd lik >>> e to put them to use. Any help would be appreciated. Garren >>> >>> ___ >>> time-nuts mailing list -- time-nuts@febo.com >>> To unsubscribe, go to >>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>> and follow the instructions there. >>> >> >> >> >> This message and any attached documents contain information from QLogic >> Corporation or its wholly-owned subsidiaries that may be confidential. If >> you are not the intended recipient, you may not read, copy, distribute, or >> use this information. If you have received this transmission in error, >> please notify the sender immediately by reply e-mail and then delete this >> message. >> >> ___ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. > > ___ > time-nuts mailing list -- time-nuts@febo.com > To un
Re: [time-nuts] FRK-L Rubidium
Hi The +12 V supply at 60 ma likely means that the heater in the OCXO is not working. If you have 60 ma on the -12 V supply, it's pulling about 10X more than it should. Bob On Feb 9, 2013, at 10:01 AM, Garren Davis wrote: > Thanks for the reply. > I found that the 12v current is only 60ma. I suppose that means the Osc. > heater is not working. I'm not having much luck with this time nuts stuff. > First the FRK and now the thunderbolt. Guess I'll start looking for another > one. > > Garren > > > > > On Feb 9, 2013, at 6:01 AM, "Bob Camp" wrote: > >> Hi >> >> DAC clamped at -5 volts suggests that the TBolt has issues. First thing to >> check is the -12 volt supply. If it's missing, the DAC will indicate -5 on >> the screen and be sitting at 0 in real life. There are a couple other things >> in the DAC circuit that can make it malfunction. >> >> Bob >> >> On Feb 9, 2013, at 1:09 AM, Garren Davis wrote: >> >>> >>> Well for some reason the 10 Mhz stopped working on the FRK. Don't know why. >>> Started up the thunderbolt. It acquired satellites but then the DAC voltage >>> went to -5 volts. It's been there for an hour. Will this change after the >>> unit stabilizes? Going to bed. Will check it tomorrow. >>> >>> Garren >>> >>> >>> >>> >>> On Feb 8, 2013, at 8:25 PM, "Ed Palmer" wrote: >>> Hi Garren, I suggest that you get the Thunderbolt working first. Without a known 10 MHz source to compare to, you're flying blind. Once the Tbolt is running, you should be able to check the frequency of the FRK by feeding both into your scope. Trigger on the Tbolt and watch what the FRK does. You should see the trace scrolling in one direction, then slow down, then stop, then scroll the other direction. The 'stop' point is at 10 MHz. The frequency sweeps a total of 20-30 Hz so it's easy to see. If you don't see the 'stop' point, the FRK isn't getting to 10 MHz. Now use the best frequency counter you've got to measure the Tbolt. Regardless of the calibration of your counter, the number your counter gives you becomes your 'new' 10 MHz. Now measure the FRK to see if it's running fast or slow. You should check the temperature of the lamp. It's easy to get at by removing the cover in the center of the heat sink. Probably best to remove the cover and then power down before you go poking around inside! The temperature of the cavity is also important, but getting to it is more of a hassle - don't go there if you don't have to. Of course, check for the normal things like internal power supply voltages, ripple, current drain (both initial and steady-state), etc. Regarding your second message, yes, the adjustment under the heat sink near the edge is the C-field. That won't help you at this point. The adjustment in the center of one side is the VCO. You could try adjusting it, but like I said, you're flying blind at this point. You won't know if you're adjusting closer to 10 MHz or further away. Good luck, Ed On 2/8/2013 6:12 PM, Garren Davis wrote: > Been lurking on the list for a while and finally started playing with a > FRK-L rubidium frequency standard. I've had this thing for a while and > decided to power it up and see what it would do. I do not get a lock. > What I see is the lamp voltage at 8.54 volts which I think is good but > the xtal control voltage swings from 2 volts to 15 volts and back to 2 > volts and keeps cycling like that. I don't have a good frequency counter > but I have a 3 Ghz 40 G/sample scope and it shows that the 10 MHz signal > is there. I just don't know how accurate it is. Has anyone seen a problem > like this? Can anyone point me to a place to start debugging this? I have > the schematics and test tools. I am a test engineer so I'm not afraid to > poke around in the guts of this thing. Hopefully I can get this thing > running. I also have a thunderbolt that I'll get running this weekend. I > don't know how deep I'll get into this time-nuts thing but I have this > nice scope and a Wavecrest sitting in my garage > a >> n >>> d I'd lik e to put them to use. Any help would be appreciated. > > Garren ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. >>> >>> >>> >>> This message and any attached documents contain information from QLogic >>> Corporation or its wholly-owned subsidiaries that may be confidential. If >>> you are not the intended recipient, you may not read, copy, distribute, or >>> use this information. If you have received this transm
Re: [time-nuts] FRK-L Rubidium
Thanks for the reply. I found that the 12v current is only 60ma. I suppose that means the Osc. heater is not working. I'm not having much luck with this time nuts stuff. First the FRK and now the thunderbolt. Guess I'll start looking for another one. Garren On Feb 9, 2013, at 6:01 AM, "Bob Camp" wrote: > Hi > > DAC clamped at -5 volts suggests that the TBolt has issues. First thing to > check is the -12 volt supply. If it's missing, the DAC will indicate -5 on > the screen and be sitting at 0 in real life. There are a couple other things > in the DAC circuit that can make it malfunction. > > Bob > > On Feb 9, 2013, at 1:09 AM, Garren Davis wrote: > >> >> Well for some reason the 10 Mhz stopped working on the FRK. Don't know why. >> Started up the thunderbolt. It acquired satellites but then the DAC voltage >> went to -5 volts. It's been there for an hour. Will this change after the >> unit stabilizes? Going to bed. Will check it tomorrow. >> >> Garren >> >> >> >> >> On Feb 8, 2013, at 8:25 PM, "Ed Palmer" wrote: >> >>> Hi Garren, >>> >>> I suggest that you get the Thunderbolt working first. Without a known 10 >>> MHz source to compare to, you're flying blind. Once the Tbolt is running, >>> you should be able to check the frequency of the FRK by feeding both into >>> your scope. Trigger on the Tbolt and watch what the FRK does. You should >>> see the trace scrolling in one direction, then slow down, then stop, then >>> scroll the other direction. The 'stop' point is at 10 MHz. The frequency >>> sweeps a total of 20-30 Hz so it's easy to see. If you don't see the >>> 'stop' point, the FRK isn't getting to 10 MHz. Now use the best frequency >>> counter you've got to measure the Tbolt. Regardless of the calibration of >>> your counter, the number your counter gives you becomes your 'new' 10 MHz. >>> Now measure the FRK to see if it's running fast or slow. >>> >>> You should check the temperature of the lamp. It's easy to get at by >>> removing the cover in the center of the heat sink. Probably best to remove >>> the cover and then power down before you go poking around inside! The >>> temperature of the cavity is also important, but getting to it is more of a >>> hassle - don't go there if you don't have to. >>> >>> Of course, check for the normal things like internal power supply voltages, >>> ripple, current drain (both initial and steady-state), etc. >>> >>> Regarding your second message, yes, the adjustment under the heat sink near >>> the edge is the C-field. That won't help you at this point. The >>> adjustment in the center of one side is the VCO. You could try adjusting >>> it, but like I said, you're flying blind at this point. You won't know if >>> you're adjusting closer to 10 MHz or further away. >>> >>> Good luck, >>> >>> Ed >>> >>> >>> On 2/8/2013 6:12 PM, Garren Davis wrote: Been lurking on the list for a while and finally started playing with a FRK-L rubidium frequency standard. I've had this thing for a while and decided to power it up and see what it would do. I do not get a lock. What I see is the lamp voltage at 8.54 volts which I think is good but the xtal control voltage swings from 2 volts to 15 volts and back to 2 volts and keeps cycling like that. I don't have a good frequency counter but I have a 3 Ghz 40 G/sample scope and it shows that the 10 MHz signal is there. I just don't know how accurate it is. Has anyone seen a problem like this? Can anyone point me to a place to start debugging this? I have the schematics and test tools. I am a test engineer so I'm not afraid to poke around in the guts of this thing. Hopefully I can get this thing running. I also have a thunderbolt that I'll get running this weekend. I don't know how deep I'll get into this time-nuts thing but I have this nice scope and a Wavecrest sitting in my garage a > n >> d >>> I'd lik >>> e to put them to use. Any help would be appreciated. Garren >>> >>> ___ >>> time-nuts mailing list -- time-nuts@febo.com >>> To unsubscribe, go to >>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>> and follow the instructions there. >>> >> >> >> >> This message and any attached documents contain information from QLogic >> Corporation or its wholly-owned subsidiaries that may be confidential. If >> you are not the intended recipient, you may not read, copy, distribute, or >> use this information. If you have received this transmission in error, >> please notify the sender immediately by reply e-mail and then delete this >> message. >> >> ___ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. > >
Re: [time-nuts] FRK-L Rubidium
Hi How old is the FRK? Does it look like it's been run without a heat sink for very long? They tend to get flaky if run for a while (many months) without heat sinking. There's nothing mysterious about it. The MTBF of the parts gets noticeably worse as the unit heats up. Bob On Feb 9, 2013, at 1:09 AM, Garren Davis wrote: > > Well for some reason the 10 Mhz stopped working on the FRK. Don't know why. > Started up the thunderbolt. It acquired satellites but then the DAC voltage > went to -5 volts. It's been there for an hour. Will this change after the > unit stabilizes? Going to bed. Will check it tomorrow. > > Garren > > > > > On Feb 8, 2013, at 8:25 PM, "Ed Palmer" wrote: > >> Hi Garren, >> >> I suggest that you get the Thunderbolt working first. Without a known 10 >> MHz source to compare to, you're flying blind. Once the Tbolt is running, >> you should be able to check the frequency of the FRK by feeding both into >> your scope. Trigger on the Tbolt and watch what the FRK does. You should >> see the trace scrolling in one direction, then slow down, then stop, then >> scroll the other direction. The 'stop' point is at 10 MHz. The frequency >> sweeps a total of 20-30 Hz so it's easy to see. If you don't see the 'stop' >> point, the FRK isn't getting to 10 MHz. Now use the best frequency counter >> you've got to measure the Tbolt. Regardless of the calibration of your >> counter, the number your counter gives you becomes your 'new' 10 MHz. Now >> measure the FRK to see if it's running fast or slow. >> >> You should check the temperature of the lamp. It's easy to get at by >> removing the cover in the center of the heat sink. Probably best to remove >> the cover and then power down before you go poking around inside! The >> temperature of the cavity is also important, but getting to it is more of a >> hassle - don't go there if you don't have to. >> >> Of course, check for the normal things like internal power supply voltages, >> ripple, current drain (both initial and steady-state), etc. >> >> Regarding your second message, yes, the adjustment under the heat sink near >> the edge is the C-field. That won't help you at this point. The adjustment >> in the center of one side is the VCO. You could try adjusting it, but like >> I said, you're flying blind at this point. You won't know if you're >> adjusting closer to 10 MHz or further away. >> >> Good luck, >> >> Ed >> >> >> On 2/8/2013 6:12 PM, Garren Davis wrote: >>> Been lurking on the list for a while and finally started playing with a >>> FRK-L rubidium frequency standard. I've had this thing for a while and >>> decided to power it up and see what it would do. I do not get a lock. What >>> I see is the lamp voltage at 8.54 volts which I think is good but the xtal >>> control voltage swings from 2 volts to 15 volts and back to 2 volts and >>> keeps cycling like that. I don't have a good frequency counter but I have a >>> 3 Ghz 40 G/sample scope and it shows that the 10 MHz signal is there. I >>> just don't know how accurate it is. Has anyone seen a problem like this? >>> Can anyone point me to a place to start debugging this? I have the >>> schematics and test tools. I am a test engineer so I'm not afraid to poke >>> around in the guts of this thing. Hopefully I can get this thing running. I >>> also have a thunderbolt that I'll get running this weekend. I don't know >>> how deep I'll get into this time-nuts thing but I have this nice scope and >>> a Wavecrest sitting in my garage an > d >> I'd lik >> e to put them to use. Any help would be appreciated. >>> >>> Garren >> >> ___ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> > > > > This message and any attached documents contain information from QLogic > Corporation or its wholly-owned subsidiaries that may be confidential. If you > are not the intended recipient, you may not read, copy, distribute, or use > this information. If you have received this transmission in error, please > notify the sender immediately by reply e-mail and then delete this message. > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FRK-L Rubidium
Hi DAC clamped at -5 volts suggests that the TBolt has issues. First thing to check is the -12 volt supply. If it's missing, the DAC will indicate -5 on the screen and be sitting at 0 in real life. There are a couple other things in the DAC circuit that can make it malfunction. Bob On Feb 9, 2013, at 1:09 AM, Garren Davis wrote: > > Well for some reason the 10 Mhz stopped working on the FRK. Don't know why. > Started up the thunderbolt. It acquired satellites but then the DAC voltage > went to -5 volts. It's been there for an hour. Will this change after the > unit stabilizes? Going to bed. Will check it tomorrow. > > Garren > > > > > On Feb 8, 2013, at 8:25 PM, "Ed Palmer" wrote: > >> Hi Garren, >> >> I suggest that you get the Thunderbolt working first. Without a known 10 >> MHz source to compare to, you're flying blind. Once the Tbolt is running, >> you should be able to check the frequency of the FRK by feeding both into >> your scope. Trigger on the Tbolt and watch what the FRK does. You should >> see the trace scrolling in one direction, then slow down, then stop, then >> scroll the other direction. The 'stop' point is at 10 MHz. The frequency >> sweeps a total of 20-30 Hz so it's easy to see. If you don't see the 'stop' >> point, the FRK isn't getting to 10 MHz. Now use the best frequency counter >> you've got to measure the Tbolt. Regardless of the calibration of your >> counter, the number your counter gives you becomes your 'new' 10 MHz. Now >> measure the FRK to see if it's running fast or slow. >> >> You should check the temperature of the lamp. It's easy to get at by >> removing the cover in the center of the heat sink. Probably best to remove >> the cover and then power down before you go poking around inside! The >> temperature of the cavity is also important, but getting to it is more of a >> hassle - don't go there if you don't have to. >> >> Of course, check for the normal things like internal power supply voltages, >> ripple, current drain (both initial and steady-state), etc. >> >> Regarding your second message, yes, the adjustment under the heat sink near >> the edge is the C-field. That won't help you at this point. The adjustment >> in the center of one side is the VCO. You could try adjusting it, but like >> I said, you're flying blind at this point. You won't know if you're >> adjusting closer to 10 MHz or further away. >> >> Good luck, >> >> Ed >> >> >> On 2/8/2013 6:12 PM, Garren Davis wrote: >>> Been lurking on the list for a while and finally started playing with a >>> FRK-L rubidium frequency standard. I've had this thing for a while and >>> decided to power it up and see what it would do. I do not get a lock. What >>> I see is the lamp voltage at 8.54 volts which I think is good but the xtal >>> control voltage swings from 2 volts to 15 volts and back to 2 volts and >>> keeps cycling like that. I don't have a good frequency counter but I have a >>> 3 Ghz 40 G/sample scope and it shows that the 10 MHz signal is there. I >>> just don't know how accurate it is. Has anyone seen a problem like this? >>> Can anyone point me to a place to start debugging this? I have the >>> schematics and test tools. I am a test engineer so I'm not afraid to poke >>> around in the guts of this thing. Hopefully I can get this thing running. I >>> also have a thunderbolt that I'll get running this weekend. I don't know >>> how deep I'll get into this time-nuts thing but I have this nice scope and >>> a Wavecrest sitting in my garage an > d >> I'd lik >> e to put them to use. Any help would be appreciated. >>> >>> Garren >> >> ___ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> > > > > This message and any attached documents contain information from QLogic > Corporation or its wholly-owned subsidiaries that may be confidential. If you > are not the intended recipient, you may not read, copy, distribute, or use > this information. If you have received this transmission in error, please > notify the sender immediately by reply e-mail and then delete this message. > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FRK-L Rubidium
Do you have the service manual? If not, get it here... http://www.ko4bb.com/manuals/index.php?dir=05%29_GPS_Timing/Efratom As I recall there's pretty good trouble shooting in the manual. Several years ago I fixed an FRK-H that wouldn't lock. The crystal osc had drifted enough that the trimmer didn't have enough range to tune to the lock freq. Fix was to pull one small cap that was in parallel with the trimmer. (C-11 on Osc schematic A21.) If you have a counter that you trust, it should be easy to see if tuning is reasonable. The manual will show where the trimmer is. I think I recall looking at the modulation signal as shown in fig 3-2 in the manual as I didn't have an accurately calibrated counter at the time. (I wasn't able to get to a balanced 2fm output signal until I modified the circuit.) On 2/8/2013 6:50 PM, Garren Davis wrote: I've let it run for hours and it gets warm. It has a heat sink and it all gets warm. There are two adjustment screws. One under the heat sink and one on the side of the unit. Is one for the vco and the other for the C-field? On Feb 8, 2013, at 4:53 PM, "jmfranke" wrote: How long do you let it run? Does the crystal oscillator oven get warm? If you let it run more than 15 minutes, and the oven gets hot, the next thing to check is the output frequency range as the tuning voltage sweeps. Not having a frequency counter hurts but there are other methods. One is to use WWV on 10 MHz. You should hear the output slowly sweep through WWV, first on one side of zero beat and then through zero beat to the other side. If the beat stays on one side, the VCO needs tweaking to get the sweep somewhat symmetrical about the 10 MHz WWV signal. John WA4WDL -- From: "Garren Davis" Sent: Friday, February 08, 2013 7:12 PM To: Subject: [time-nuts] FRK-L Rubidium Been lurking on the list for a while and finally started playing with a FRK-L rubidium frequency standard. I've had this thing for a while and decided to power it up and see what it would do. I do not get a lock. What I see is the lamp voltage at 8.54 volts which I think is good but the xtal control voltage swings from 2 volts to 15 volts and back to 2 volts and keeps cycling like that. I don't have a good frequency counter but I have a 3 Ghz 40 G/sample scope and it shows that the 10 MHz signal is there. I just don't know how accurate it is. Has anyone seen a problem like this? Can anyone point me to a place to start debugging this? I have the schematics and test tools. I am a test engineer so I'm not afraid to poke around in the guts of this thing. Hopefully I can get this thing running. I also have a thunderbolt that I'll get running this weekend. I don't know how deep I'll get into this time-nuts thing but I have this nice scope and a Wavecrest sitting in my garage and I'd like to put them to use. Any help would be appreciated. Garren ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FRK-L Rubidium
Well for some reason the 10 Mhz stopped working on the FRK. Don't know why. Started up the thunderbolt. It acquired satellites but then the DAC voltage went to -5 volts. It's been there for an hour. Will this change after the unit stabilizes? Going to bed. Will check it tomorrow. Garren On Feb 8, 2013, at 8:25 PM, "Ed Palmer" wrote: > Hi Garren, > > I suggest that you get the Thunderbolt working first. Without a known 10 MHz > source to compare to, you're flying blind. Once the Tbolt is running, you > should be able to check the frequency of the FRK by feeding both into your > scope. Trigger on the Tbolt and watch what the FRK does. You should see the > trace scrolling in one direction, then slow down, then stop, then scroll the > other direction. The 'stop' point is at 10 MHz. The frequency sweeps a > total of 20-30 Hz so it's easy to see. If you don't see the 'stop' point, > the FRK isn't getting to 10 MHz. Now use the best frequency counter you've > got to measure the Tbolt. Regardless of the calibration of your counter, the > number your counter gives you becomes your 'new' 10 MHz. Now measure the FRK > to see if it's running fast or slow. > > You should check the temperature of the lamp. It's easy to get at by > removing the cover in the center of the heat sink. Probably best to remove > the cover and then power down before you go poking around inside! The > temperature of the cavity is also important, but getting to it is more of a > hassle - don't go there if you don't have to. > > Of course, check for the normal things like internal power supply voltages, > ripple, current drain (both initial and steady-state), etc. > > Regarding your second message, yes, the adjustment under the heat sink near > the edge is the C-field. That won't help you at this point. The adjustment > in the center of one side is the VCO. You could try adjusting it, but like I > said, you're flying blind at this point. You won't know if you're adjusting > closer to 10 MHz or further away. > > Good luck, > > Ed > > > On 2/8/2013 6:12 PM, Garren Davis wrote: >> Been lurking on the list for a while and finally started playing with a >> FRK-L rubidium frequency standard. I've had this thing for a while and >> decided to power it up and see what it would do. I do not get a lock. What I >> see is the lamp voltage at 8.54 volts which I think is good but the xtal >> control voltage swings from 2 volts to 15 volts and back to 2 volts and >> keeps cycling like that. I don't have a good frequency counter but I have a >> 3 Ghz 40 G/sample scope and it shows that the 10 MHz signal is there. I just >> don't know how accurate it is. Has anyone seen a problem like this? Can >> anyone point me to a place to start debugging this? I have the schematics >> and test tools. I am a test engineer so I'm not afraid to poke around in the >> guts of this thing. Hopefully I can get this thing running. I also have a >> thunderbolt that I'll get running this weekend. I don't know how deep I'll >> get into this time-nuts thing but I have this nice scope and a Wavecrest >> sitting in my garage and > I'd lik > e to put them to use. Any help would be appreciated. >> >> Garren > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > This message and any attached documents contain information from QLogic Corporation or its wholly-owned subsidiaries that may be confidential. If you are not the intended recipient, you may not read, copy, distribute, or use this information. If you have received this transmission in error, please notify the sender immediately by reply e-mail and then delete this message. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FRK-L Rubidium
Hi Garren, I suggest that you get the Thunderbolt working first. Without a known 10 MHz source to compare to, you're flying blind. Once the Tbolt is running, you should be able to check the frequency of the FRK by feeding both into your scope. Trigger on the Tbolt and watch what the FRK does. You should see the trace scrolling in one direction, then slow down, then stop, then scroll the other direction. The 'stop' point is at 10 MHz. The frequency sweeps a total of 20-30 Hz so it's easy to see. If you don't see the 'stop' point, the FRK isn't getting to 10 MHz. Now use the best frequency counter you've got to measure the Tbolt. Regardless of the calibration of your counter, the number your counter gives you becomes your 'new' 10 MHz. Now measure the FRK to see if it's running fast or slow. You should check the temperature of the lamp. It's easy to get at by removing the cover in the center of the heat sink. Probably best to remove the cover and then power down before you go poking around inside! The temperature of the cavity is also important, but getting to it is more of a hassle - don't go there if you don't have to. Of course, check for the normal things like internal power supply voltages, ripple, current drain (both initial and steady-state), etc. Regarding your second message, yes, the adjustment under the heat sink near the edge is the C-field. That won't help you at this point. The adjustment in the center of one side is the VCO. You could try adjusting it, but like I said, you're flying blind at this point. You won't know if you're adjusting closer to 10 MHz or further away. Good luck, Ed On 2/8/2013 6:12 PM, Garren Davis wrote: Been lurking on the list for a while and finally started playing with a FRK-L rubidium frequency standard. I've had this thing for a while and decided to power it up and see what it would do. I do not get a lock. What I see is the lamp voltage at 8.54 volts which I think is good but the xtal control voltage swings from 2 volts to 15 volts and back to 2 volts and keeps cycling like that. I don't have a good frequency counter but I have a 3 Ghz 40 G/sample scope and it shows that the 10 MHz signal is there. I just don't know how accurate it is. Has anyone seen a problem like this? Can anyone point me to a place to start debugging this? I have the schematics and test tools. I am a test engineer so I'm not afraid to poke around in the guts of this thing. Hopefully I can get this thing running. I also have a thunderbolt that I'll get running this weekend. I don't know how deep I'll get into this time-nuts thing but I have this nice scope and a Wavecrest sitting in my garage and I'd lik e to put them to use. Any help would be appreciated. Garren ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FRK-L Rubidium
I've let it run for hours and it gets warm. It has a heat sink and it all gets warm. There are two adjustment screws. One under the heat sink and one on the side of the unit. Is one for the vco and the other for the C-field? On Feb 8, 2013, at 4:53 PM, "jmfranke" wrote: > How long do you let it run? Does the crystal oscillator oven get warm? If you > let it run more than 15 minutes, and the oven gets hot, the next thing to > check is the output frequency range as the tuning voltage sweeps. Not having > a frequency counter hurts but there are other methods. One is to use WWV on > 10 MHz. You should hear the output slowly sweep through WWV, first on one > side of zero beat and then through zero beat to the other side. If the beat > stays on one side, the VCO needs tweaking to get the sweep somewhat > symmetrical about the 10 MHz WWV signal. > > John WA4WDL > > -- > From: "Garren Davis" > Sent: Friday, February 08, 2013 7:12 PM > To: > Subject: [time-nuts] FRK-L Rubidium > >> >> Been lurking on the list for a while and finally started playing with a >> FRK-L rubidium frequency standard. I've had >> this thing for a while and decided to power it up and see what it would do. >> I do not get a lock. What I see is the >> lamp voltage at 8.54 volts which I think is good but the xtal control >> voltage swings from 2 volts to 15 volts and back >> to 2 volts and keeps cycling like that. I don't have a good frequency >> counter but I have a 3 Ghz 40 G/sample scope >> and it shows that the 10 MHz signal is there. I just don't know how accurate >> it is. Has anyone seen a problem like >> this? Can anyone point me to a place to start debugging this? I have the >> schematics and test tools. I am a test >> engineer so I'm not afraid to poke around in the guts of this thing. >> Hopefully I can get this thing running. I also >> have a thunderbolt that I'll get running this weekend. I don't know how deep >> I'll get into this time-nuts thing but >> I have this nice scope and a Wavecrest sitting in my garage and I'd like to >> put them to use. Any help would be appreciated. >> >> Garren >> >> >> >> This message and any attached documents contain information from QLogic >> Corporation or its wholly-owned subsidiaries that may be confidential. If >> you are not the intended recipient, you may not read, copy, distribute, or >> use this information. If you have received this transmission in error, >> please notify the sender immediately by reply e-mail and then delete this >> message. >> ___ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > This message and any attached documents contain information from QLogic Corporation or its wholly-owned subsidiaries that may be confidential. If you are not the intended recipient, you may not read, copy, distribute, or use this information. If you have received this transmission in error, please notify the sender immediately by reply e-mail and then delete this message. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FRK-L Rubidium
Hi First thing to check is indeed the frequency of the 10 MHz oscillator. There's a good chance it's simply aged far enough that it will no longer lock up. If the drift isn't super far, the oscillator can be adjusted. The TBolt and a good counter will tell you everything you need to know about the 10 MHz. If the oscillator is sweeping past the correct frequency, the next thing to check is the output of the SRD assembly. Your scope should be able to "see" that signal. If it's missing, then track it back down the multiplier chain. Bob On Feb 8, 2013, at 7:12 PM, Garren Davis wrote: > > Been lurking on the list for a while and finally started playing with a FRK-L > rubidium frequency standard. I've had > this thing for a while and decided to power it up and see what it would do. I > do not get a lock. What I see is the > lamp voltage at 8.54 volts which I think is good but the xtal control voltage > swings from 2 volts to 15 volts and back > to 2 volts and keeps cycling like that. I don't have a good frequency counter > but I have a 3 Ghz 40 G/sample scope > and it shows that the 10 MHz signal is there. I just don't know how accurate > it is. Has anyone seen a problem like > this? Can anyone point me to a place to start debugging this? I have the > schematics and test tools. I am a test > engineer so I'm not afraid to poke around in the guts of this thing. > Hopefully I can get this thing running. I also > have a thunderbolt that I'll get running this weekend. I don't know how deep > I'll get into this time-nuts thing but > I have this nice scope and a Wavecrest sitting in my garage and I'd like to > put them to use. Any help would be appreciated. > > Garren > > > > This message and any attached documents contain information from QLogic > Corporation or its wholly-owned subsidiaries that may be confidential. If you > are not the intended recipient, you may not read, copy, distribute, or use > this information. If you have received this transmission in error, please > notify the sender immediately by reply e-mail and then delete this message. > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FRK-L Rubidium
How long do you let it run? Does the crystal oscillator oven get warm? If you let it run more than 15 minutes, and the oven gets hot, the next thing to check is the output frequency range as the tuning voltage sweeps. Not having a frequency counter hurts but there are other methods. One is to use WWV on 10 MHz. You should hear the output slowly sweep through WWV, first on one side of zero beat and then through zero beat to the other side. If the beat stays on one side, the VCO needs tweaking to get the sweep somewhat symmetrical about the 10 MHz WWV signal. John WA4WDL -- From: "Garren Davis" Sent: Friday, February 08, 2013 7:12 PM To: Subject: [time-nuts] FRK-L Rubidium Been lurking on the list for a while and finally started playing with a FRK-L rubidium frequency standard. I've had this thing for a while and decided to power it up and see what it would do. I do not get a lock. What I see is the lamp voltage at 8.54 volts which I think is good but the xtal control voltage swings from 2 volts to 15 volts and back to 2 volts and keeps cycling like that. I don't have a good frequency counter but I have a 3 Ghz 40 G/sample scope and it shows that the 10 MHz signal is there. I just don't know how accurate it is. Has anyone seen a problem like this? Can anyone point me to a place to start debugging this? I have the schematics and test tools. I am a test engineer so I'm not afraid to poke around in the guts of this thing. Hopefully I can get this thing running. I also have a thunderbolt that I'll get running this weekend. I don't know how deep I'll get into this time-nuts thing but I have this nice scope and a Wavecrest sitting in my garage and I'd like to put them to use. Any help would be appreciated. Garren This message and any attached documents contain information from QLogic Corporation or its wholly-owned subsidiaries that may be confidential. If you are not the intended recipient, you may not read, copy, distribute, or use this information. If you have received this transmission in error, please notify the sender immediately by reply e-mail and then delete this message. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] FRK-L Rubidium
Been lurking on the list for a while and finally started playing with a FRK-L rubidium frequency standard. I've had this thing for a while and decided to power it up and see what it would do. I do not get a lock. What I see is the lamp voltage at 8.54 volts which I think is good but the xtal control voltage swings from 2 volts to 15 volts and back to 2 volts and keeps cycling like that. I don't have a good frequency counter but I have a 3 Ghz 40 G/sample scope and it shows that the 10 MHz signal is there. I just don't know how accurate it is. Has anyone seen a problem like this? Can anyone point me to a place to start debugging this? I have the schematics and test tools. I am a test engineer so I'm not afraid to poke around in the guts of this thing. Hopefully I can get this thing running. I also have a thunderbolt that I'll get running this weekend. I don't know how deep I'll get into this time-nuts thing but I have this nice scope and a Wavecrest sitting in my garage and I'd like to put them to use. Any help would be appreciated. Garren This message and any attached documents contain information from QLogic Corporation or its wholly-owned subsidiaries that may be confidential. If you are not the intended recipient, you may not read, copy, distribute, or use this information. If you have received this transmission in error, please notify the sender immediately by reply e-mail and then delete this message. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FRK specs.....
Hi Don, > > Bert: > Interesting. > > I, too, have a couple of the HP 10811 oven-oscillators sitting on the > shelf for several years, waiting for a project. I want to 'discipline' > them, but really do not know how. Also look at John's modification of a Thunderbolt. http://www.ke5fx.com/tbolt.htm -- Björn ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FRK specs.....
Me too, please. -Brian, WA1ZMS -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of dlewis6...@austin.rr.com Sent: Sunday, August 12, 2012 2:55 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] FRK specs. Bert: Interesting. I, too, have a couple of the HP 10811 oven-oscillators sitting on the shelf for several years, waiting for a project. I want to 'discipline' them, but really do not know how. Could you kindly mark up the HP 10811 schematic and/or please tell me what to cut, ... what to jumper??? Thanks a lot! Don Lewis Austin, TX -- == ewkeh...@aol.com wrote: > In the commercial world a PRS10 is most likely the best but for time > nuts even at the surplus price in my opinion it is all hype and a > waste of money. Have you looked closely at the specification and the > design. Frequency accuracy can not be better than 1 E-12 since the > OCXO is driven strictly by a DAC and the A/V is for time nuts nothing > to write home about. Any digital loop controlling a Rb in tern with an > analog loop controlling a selected HP 10811 or for that matter a Morion will outperform a PRS 10. > I have a FRK-H controlling a HP 10811 that has an A/V below 1 E-12 > from 1 to 100 seconds, I modified the FRK loop and the 10811. On the > 10811 it is easy to get to the bottom PCB and without un soldering any > component or further disassembly cutting two traces and two jumpers > you end up with a 2 to 12 Volt tuning voltage, perfect for a FRK or > M100.. A second option is to use a separate analog loop with a time constant suitable for your OCXO. > By the way the FRK-H is not lower noise but factor 2 lower aging with > the proper OCXO not an issue, since hopefully you discipline it with GPS. > For 12 years I have used Shera in that application recently switching > the DAC to a LTC1655. Has served me well over the years. > Other Rb's will do also a very credible job. On one extreme a FEI 5680 > is waiting to be integrated with a MV180 on the other extreme a HP5065 > RVFR assembly will be integrated with a M1000 OCXO along with state of > the art circuitry. > Bert Kehren > > > > In a message dated 8/12/2012 8:09:54 A.M. Eastern Daylight Time, > wa1...@att.net writes: > > Thanks Tom. > > I agree, the SRS seems to be the best > overall Rb except maybe on old HP if one is willing to spend about the > same price on a 20 year old unit. The SRS units I bought for work were > only > $2700 with chassis, rack ears and multiple outputs. > > > > -Brian, WA1ZMS > > On Aug 12, 2012, at 3:17 AM, Tom Knox wrote: > > > > > Hi Brian; > > There are a few decent rubidium oscillators short term like the SRS > > but > none are great, in my humble opinion you are much better off > disciplining a good quartz oscillator off your LPRO. > > Best Wishes; > > Thomas Knox > > > > > > > >> From: wa1...@att.net > >> Date: Sat, 11 Aug 2012 21:56:13 -0700 > >> To: time-nuts@febo.com > >> Subject: [time-nuts] FRK specs. > >> > >> I used to be of the opinion that the Efratom FRK-H was the best of > >> the > models of FRK Rb standards for both short-term stability and overall > performance. > >> > >> Is that still true today? > >> > >> I know there are better solutions for short-term (BVA OCXO) and > >> long > term > >> (Cs & MASERS). But where to things stack up today? > >> > >> I'm looking to buy an Rb that's better than my LPROs and other models. > >> But I do not own an FRK-H. > >> > >> Looking for comments, please. > >> > >> Thanks in advance, > >> -Brian, WA1ZMS > >> ___ > >> time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > >> and follow the instructions there. > > > > ___ > > time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions there. > > ___ > time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > ___ > time-nuts mailing list -- time-nuts@f
Re: [time-nuts] FRK specs.....
Bert: Interesting. I, too, have a couple of the HP 10811 oven-oscillators sitting on the shelf for several years, waiting for a project. I want to 'discipline' them, but really do not know how. Could you kindly mark up the HP 10811 schematic and/or please tell me what to cut, ... what to jumper??? Thanks a lot! Don Lewis Austin, TX -- == ewkeh...@aol.com wrote: > In the commercial world a PRS10 is most likely the best but for time nuts > even at the surplus price in my opinion it is all hype and a waste of > money. Have you looked closely at the specification and the design. Frequency > accuracy can not be better than 1 E-12 since the OCXO is driven strictly by a > DAC and the A/V is for time nuts nothing to write home about. Any digital > loop controlling a Rb in tern with an analog loop controlling a selected > HP 10811 or for that matter a Morion will outperform a PRS 10. > I have a FRK-H controlling a HP 10811 that has an A/V below 1 E-12 from 1 > to 100 seconds, I modified the FRK loop and the 10811. On the 10811 it is > easy to get to the bottom PCB and without un soldering any component or > further disassembly cutting two traces and two jumpers you end up with a 2 to > 12 > Volt tuning voltage, perfect for a FRK or M100.. A second option is to use > a separate analog loop with a time constant suitable for your OCXO. > By the way the FRK-H is not lower noise but factor 2 lower aging with the > proper OCXO not an issue, since hopefully you discipline it with GPS. > For 12 years I have used Shera in that application recently switching the > DAC to a LTC1655. Has served me well over the years. > Other Rb's will do also a very credible job. On one extreme a FEI 5680 is > waiting to be integrated with a MV180 on the other extreme a HP5065 RVFR > assembly will be integrated with a M1000 OCXO along with state of the art > circuitry. > Bert Kehren > > > > In a message dated 8/12/2012 8:09:54 A.M. Eastern Daylight Time, > wa1...@att.net writes: > > Thanks Tom. > > I agree, the SRS seems to be the best > overall Rb except maybe on old HP if one is willing to spend about the > same price on a 20 year old unit. The SRS units I bought for work were only > $2700 with chassis, rack ears and multiple outputs. > > > > -Brian, WA1ZMS > > On Aug 12, 2012, at 3:17 AM, Tom Knox wrote: > > > > > Hi Brian; > > There are a few decent rubidium oscillators short term like the SRS but > none are great, in my humble opinion you are much better off disciplining a > good quartz oscillator off your LPRO. > > Best Wishes; > > Thomas Knox > > > > > > > >> From: wa1...@att.net > >> Date: Sat, 11 Aug 2012 21:56:13 -0700 > >> To: time-nuts@febo.com > >> Subject: [time-nuts] FRK specs. > >> > >> I used to be of the opinion that the Efratom FRK-H was the best of the > models of FRK Rb standards for both short-term stability and overall > performance. > >> > >> Is that still true today? > >> > >> I know there are better solutions for short-term (BVA OCXO) and long > term > >> (Cs & MASERS). But where to things stack up today? > >> > >> I'm looking to buy an Rb that's better than my LPROs and other models. > >> But I do not own an FRK-H. > >> > >> Looking for comments, please. > >> > >> Thanks in advance, > >> -Brian, WA1ZMS > >> ___ > >> time-nuts mailing list -- time-nuts@febo.com > >> To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > >> and follow the instructions there. > > > > ___ > > time-nuts mailing list -- time-nuts@febo.com > > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions there. > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FRK specs.....
In the commercial world a PRS10 is most likely the best but for time nuts even at the surplus price in my opinion it is all hype and a waste of money. Have you looked closely at the specification and the design. Frequency accuracy can not be better than 1 E-12 since the OCXO is driven strictly by a DAC and the A/V is for time nuts nothing to write home about. Any digital loop controlling a Rb in tern with an analog loop controlling a selected HP 10811 or for that matter a Morion will outperform a PRS 10. I have a FRK-H controlling a HP 10811 that has an A/V below 1 E-12 from 1 to 100 seconds, I modified the FRK loop and the 10811. On the 10811 it is easy to get to the bottom PCB and without un soldering any component or further disassembly cutting two traces and two jumpers you end up with a 2 to 12 Volt tuning voltage, perfect for a FRK or M100.. A second option is to use a separate analog loop with a time constant suitable for your OCXO. By the way the FRK-H is not lower noise but factor 2 lower aging with the proper OCXO not an issue, since hopefully you discipline it with GPS. For 12 years I have used Shera in that application recently switching the DAC to a LTC1655. Has served me well over the years. Other Rb's will do also a very credible job. On one extreme a FEI 5680 is waiting to be integrated with a MV180 on the other extreme a HP5065 RVFR assembly will be integrated with a M1000 OCXO along with state of the art circuitry. Bert Kehren In a message dated 8/12/2012 8:09:54 A.M. Eastern Daylight Time, wa1...@att.net writes: Thanks Tom. I agree, the SRS seems to be the best overall Rb except maybe on old HP if one is willing to spend about the same price on a 20 year old unit. The SRS units I bought for work were only $2700 with chassis, rack ears and multiple outputs. -Brian, WA1ZMS On Aug 12, 2012, at 3:17 AM, Tom Knox wrote: > > Hi Brian; > There are a few decent rubidium oscillators short term like the SRS but none are great, in my humble opinion you are much better off disciplining a good quartz oscillator off your LPRO. > Best Wishes; > Thomas Knox > > > >> From: wa1...@att.net >> Date: Sat, 11 Aug 2012 21:56:13 -0700 >> To: time-nuts@febo.com >> Subject: [time-nuts] FRK specs. >> >> I used to be of the opinion that the Efratom FRK-H was the best of the models of FRK Rb standards for both short-term stability and overall performance. >> >> Is that still true today? >> >> I know there are better solutions for short-term (BVA OCXO) and long term >> (Cs & MASERS). But where to things stack up today? >> >> I'm looking to buy an Rb that's better than my LPROs and other models. >> But I do not own an FRK-H. >> >> Looking for comments, please. >> >> Thanks in advance, >> -Brian, WA1ZMS >> ___ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FRK specs.....
Thanks Tom. I agree, the SRS seems to be the best overall Rb except maybe on old HP if one is willing to spend about the same price on a 20 year old unit. The SRS units I bought for work were only $2700 with chassis, rack ears and multiple outputs. -Brian, WA1ZMS On Aug 12, 2012, at 3:17 AM, Tom Knox wrote: > > Hi Brian; > There are a few decent rubidium oscillators short term like the SRS but none > are great, in my humble opinion you are much better off disciplining a good > quartz oscillator off your LPRO. > Best Wishes; > Thomas Knox > > > >> From: wa1...@att.net >> Date: Sat, 11 Aug 2012 21:56:13 -0700 >> To: time-nuts@febo.com >> Subject: [time-nuts] FRK specs. >> >> I used to be of the opinion that the Efratom FRK-H was the best of the >> models of FRK Rb standards for both short-term stability and overall >> performance. >> >> Is that still true today? >> >> I know there are better solutions for short-term (BVA OCXO) and long term >> (Cs & MASERS). But where to things stack up today? >> >> I'm looking to buy an Rb that's better than my LPROs and other models. >> But I do not own an FRK-H. >> >> Looking for comments, please. >> >> Thanks in advance, >> -Brian, WA1ZMS >> ___ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FRK specs.....
Hi Brian; There are a few decent rubidium oscillators short term like the SRS but none are great, in my humble opinion you are much better off disciplining a good quartz oscillator off your LPRO. Best Wishes; Thomas Knox > From: wa1...@att.net > Date: Sat, 11 Aug 2012 21:56:13 -0700 > To: time-nuts@febo.com > Subject: [time-nuts] FRK specs. > > I used to be of the opinion that the Efratom FRK-H was the best of the models > of FRK Rb standards for both short-term stability and overall performance. > > Is that still true today? > > I know there are better solutions for short-term (BVA OCXO) and long term > (Cs & MASERS). But where to things stack up today? > > I'm looking to buy an Rb that's better than my LPROs and other models. > But I do not own an FRK-H. > > Looking for comments, please. > > Thanks in advance, > -Brian, WA1ZMS > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] FRK specs.....
I used to be of the opinion that the Efratom FRK-H was the best of the models of FRK Rb standards for both short-term stability and overall performance. Is that still true today? I know there are better solutions for short-term (BVA OCXO) and long term (Cs & MASERS). But where to things stack up today? I'm looking to buy an Rb that's better than my LPROs and other models. But I do not own an FRK-H. Looking for comments, please. Thanks in advance, -Brian, WA1ZMS ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FRK and TS-105A
On 07/06/2010 06:45 PM, Rob Kimberley wrote: I assume you found manual for FRK, available at http://www.to-way.com/tf/frk.pdf It was hinted to me from Björn, thanks to your both. It has a FRK-HO, which is the low-noise variant, but offset outside the normal trimming range. I probably have one lurking in a box somewhere in my store. If I can find it, it's yours for the postage. Deal. I have a flair for hardcopy manuals. I guess I am old-fashioned. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FRK and TS-105A
I assume you found manual for FRK, available at http://www.to-way.com/tf/frk.pdf I probably have one lurking in a box somewhere in my store. If I can find it, it's yours for the postage. Rob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Magnus Danielson Sent: 06 July 2010 10:07 AM To: time-nuts@febo.com Subject: Re: [time-nuts] FRK and TS-105A On 07/06/2010 10:51 AM, Rob Kimberley wrote: > Nice acquisition! Yes, indeed. Now the curious mind wants to "dig in". :) It set me back 159 USD, which I can handle and then naturally shipping and customs. Ah well. For an "As is" condition, it is working modulus operator inexperience with the particular box. However, it is cranking out numbers and fairly easy to operate. Three push-buttons as user interface. To start a new measurement - press "Reset". :) It is clear that it used the non-overlapping ADEV, which gives it a drawback for the larger taus. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FRK and TS-105A
On 07/06/2010 10:51 AM, Rob Kimberley wrote: Nice acquisition! Yes, indeed. Now the curious mind wants to "dig in". :) It set me back 159 USD, which I can handle and then naturally shipping and customs. Ah well. For an "As is" condition, it is working modulus operator inexperience with the particular box. However, it is cranking out numbers and fairly easy to operate. Three push-buttons as user interface. To start a new measurement - press "Reset". :) It is clear that it used the non-overlapping ADEV, which gives it a drawback for the larger taus. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FRK and TS-105A
Nice acquisition! Rob K -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Magnus Danielson Sent: 06 July 2010 09:41 To: Discussion of precise time and frequency measurement Subject: [time-nuts] FRK and TS-105A Hi! Could somebody from the top of their head give me the most useful pointers on FRK rubidiums? I now have one as part of a box, and naturally I want to stash up on the information. The rubidium locks nicely, if just patiently sitting there and waiting, and the designers of the box was nice enough to dedicate a status view to the rubidium monitoring voltages and lock status. The box itself is a Ball Efratom TS-105A measurement box, which crunches out frequency offsets and allan variances for 100 ms, 1 s, 10 s and 100 s directly on the screen. All under the control of the awsome CPU powers of 6502. The box works, but I am trying to collect info on it. The box will run in either single mixer or double-mixer mode. It accepts 5 MHz and 10 MHz. Each counter channel receives a signal conditioned input and 10,1 MHz from the Rubidium. It hits the mixer after an ECL driver and is then amplified in LM108 and comparator LM111. From there will a cascade of TTL chips count it, presumably in the 10 MHz from the rubidium. For 1 s this gives a resolution of 1E-7/1E6 = 1E-13 which isn't too shabby. The only SMD component seen so far is the cap sitting directly on the mixers terminals. I have not retraced the card in detail so far, just looked at it breefly (out of curiosity naturally). If someone has manuals for the TS-105A I will be happy, TvB has promised to locate his.. This box is from 1985, so it is not cutting edge, but it is functional, direct and a bit fun, so why not. :) It would be fun if it could crank out the observables directly on serial port or so... My beast doesn't have the GPIB interface. It may be a matter of hooking up a cable, but in that case it is undocumented. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] FRK and TS-105A
Hi! Could somebody from the top of their head give me the most useful pointers on FRK rubidiums? I now have one as part of a box, and naturally I want to stash up on the information. The rubidium locks nicely, if just patiently sitting there and waiting, and the designers of the box was nice enough to dedicate a status view to the rubidium monitoring voltages and lock status. The box itself is a Ball Efratom TS-105A measurement box, which crunches out frequency offsets and allan variances for 100 ms, 1 s, 10 s and 100 s directly on the screen. All under the control of the awsome CPU powers of 6502. The box works, but I am trying to collect info on it. The box will run in either single mixer or double-mixer mode. It accepts 5 MHz and 10 MHz. Each counter channel receives a signal conditioned input and 10,1 MHz from the Rubidium. It hits the mixer after an ECL driver and is then amplified in LM108 and comparator LM111. From there will a cascade of TTL chips count it, presumably in the 10 MHz from the rubidium. For 1 s this gives a resolution of 1E-7/1E6 = 1E-13 which isn't too shabby. The only SMD component seen so far is the cap sitting directly on the mixers terminals. I have not retraced the card in detail so far, just looked at it breefly (out of curiosity naturally). If someone has manuals for the TS-105A I will be happy, TvB has promised to locate his.. This box is from 1985, so it is not cutting edge, but it is functional, direct and a bit fun, so why not. :) It would be fun if it could crank out the observables directly on serial port or so... My beast doesn't have the GPIB interface. It may be a matter of hooking up a cable, but in that case it is undocumented. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] FRK-H question
Tim, It sound like your unit is locked. Power it off for 15 minutes and then monitor the Xtal control when powering back up. It should sweep from about 2 volts to 15 volts. Within 10 minutes it should stop sweeping indicating a lock. After being locked for a few hours adjust the Xtal trim cap for around 8.5 VDC on the Xtal control pin. It may lose lock while making the adjustment, just wait till it locks again and continue until done. Then after 24 hours you can adjust the C-field adjustment to set the frequency against GPS or other known good <1X10-11th standard. There are several options for the lock pin but try this: Take a DVM (set on the ohms range that will source enough voltage to read a diodes voltage drop) from the return to the lock pin. (+ volts from ohmeter to lock pin) With the unit out of lock you should read an open, once locked it should read a low value. This is if your unit has the open collector output. If so an LED through a dropping resistor to the +24VDC supply will give you a lock light! Hope this helps! Corby Dawson ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FRK-L OK or too tired?
If the unit does not have external EFC, you can bring out the existing potentiometer circuit to the outside world , via un-used I/O pins.. Most are 1 kilo-ohm 10 to 20 turn trim pots. Replace it with a low tempco wire wound pot and use a turns counter. My unit was fairly close on frequency when I received it and the pot was set close to 500 ohms. I replaced it with a 0.1 percent 460 some ohms precision resistor, which was mounted inside the case and a 100 ohm - 10 turn pot was put in series with it , outside of the case - this combo gives about +/- 1E-10 control of the frequency. Brian - N4FMN Marco Bruno wrote: > At 23.31 07/09/2006, you wrote: > >> James and Brooke, >> >> Thanks for the informative replies. I have done pretty much what you >> suggested. The result is a nice sloped line in the positive direction, >> indicating that the FRK-L Rb source is running fast at a rate of about >> 1e-9. >> >> I checked the lamp and crystal osc monitors and both are within spec. >> The crystal mon was 5V (2-16V is the suggested range), so I adjusted it >> up to 10V with the range adjust trimmer. >> >> I don't know if an FRK-L running for 13 years is expected to be 1E-9 >> high in frequency or if the unit could use some maintenance. The >> suggested drift of 1e-11 per month would add up to 1.5 e-9 over 13 >> years, so it may well be within spec and need some C-field adjustment. >> >> Unfortunately, when it was mounted in its box, the C-field adjust hole >> was covered up. I'll need to power it down and do some disassembly and >> drilling to make that adjustment accessible. >> >> Suggestions? Comments? >> > > David, > > drill an hole, turn the trimmer and zero it. It's a perfectly > legitimate offset, > and since you see a straight line it's working well. Only it needs to > be zeroed. > > Do it after a few hours of warm up, then check it for a week and zero again. > It will stay in the usual +/- 1E-11 per day. > > If it has the EFC option, may be that the external voltage was used to correct > the drift, so it may have had even a smaller drift over it's life. > > Marco IK1ODO > > > ___ > time-nuts mailing list > time-nuts@febo.com > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] FRK-L OK or too tired?
At 23.31 07/09/2006, you wrote: >James and Brooke, > >Thanks for the informative replies. I have done pretty much what you >suggested. The result is a nice sloped line in the positive direction, >indicating that the FRK-L Rb source is running fast at a rate of about >1e-9. > >I checked the lamp and crystal osc monitors and both are within spec. >The crystal mon was 5V (2-16V is the suggested range), so I adjusted it >up to 10V with the range adjust trimmer. > >I don't know if an FRK-L running for 13 years is expected to be 1E-9 >high in frequency or if the unit could use some maintenance. The >suggested drift of 1e-11 per month would add up to 1.5 e-9 over 13 >years, so it may well be within spec and need some C-field adjustment. > >Unfortunately, when it was mounted in its box, the C-field adjust hole >was covered up. I'll need to power it down and do some disassembly and >drilling to make that adjustment accessible. > >Suggestions? Comments? David, drill an hole, turn the trimmer and zero it. It's a perfectly legitimate offset, and since you see a straight line it's working well. Only it needs to be zeroed. Do it after a few hours of warm up, then check it for a week and zero again. It will stay in the usual +/- 1E-11 per day. If it has the EFC option, may be that the external voltage was used to correct the drift, so it may have had even a smaller drift over it's life. Marco IK1ODO ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
[time-nuts] FRK-L OK or too tired?
James and Brooke, Thanks for the informative replies. I have done pretty much what you suggested. The result is a nice sloped line in the positive direction, indicating that the FRK-L Rb source is running fast at a rate of about 1e-9. I checked the lamp and crystal osc monitors and both are within spec. The crystal mon was 5V (2-16V is the suggested range), so I adjusted it up to 10V with the range adjust trimmer. I don't know if an FRK-L running for 13 years is expected to be 1E-9 high in frequency or if the unit could use some maintenance. The suggested drift of 1e-11 per month would add up to 1.5 e-9 over 13 years, so it may well be within spec and need some C-field adjustment. Unfortunately, when it was mounted in its box, the C-field adjust hole was covered up. I'll need to power it down and do some disassembly and drilling to make that adjustment accessible. Suggestions? Comments? ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] FRK-L Manual
Brian, i just sent you the 80 page "FRK (H OR L) Operating and Maintainance Manual". It is abt. 5 MB 73 Ulli > -Ursprüngliche Nachricht- > Von: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] Im Auftrag von Brian Kirby > Gesendet: Dienstag, 11. Juli 2006 05:42 > An: Discussion of precise time and frequency measurement > Betreff: [time-nuts] FRK-L Manual > > > Does anybody have a scanned copy of the FRK-L manual ? > > Brian - N4FMN > > > > ___ > time-nuts mailing list > time-nuts@febo.com > https://www.febo.com/cgi-> bin/mailman/listinfo/time-nuts > ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] FRK-L Manual
Peter, Would you please send me the FRK-L manual. Thanks, Hadley, K7MLR [EMAIL PROTECTED] At 05:38 AM 7/11/2006, you wrote: >I do, post your email address and I can send it to you. > >Peter Lacey - AA1ZU > A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed. ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] FRK-L Manual
I do, post your email address and I can send it to you. Peter Lacey - AA1ZU -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Brian Kirby Sent: Monday, July 10, 2006 11:42 PM To: Discussion of precise time and frequency measurement Subject: [time-nuts] FRK-L Manual Does anybody have a scanned copy of the FRK-L manual ? Brian - N4FMN ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
[time-nuts] FRK-L Manual
Does anybody have a scanned copy of the FRK-L manual ? Brian - N4FMN ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
