Re: [time-nuts] Basic question regarding comparing two frequencies
jim...@earthlink.net said: > But over the next few years, I suspect you'll see more and more of it > coming onto the surplus market. My fond hope is that my daughter will be > able to capitalize on it. A friend had a fancy scope with an Etherenet. It got infected with the virus-de-jour. -- These are my opinions, not necessarily my employer's. I hate spam. ___ 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] HP-3586B Tunable Voltmeter...
Burt, You still need to offset the voltmeter if you intend to use it. I think it's somewhere around 1.7dB difference. I'm not sure I have the time to fix the "B" , but if things change, I'll contact you for advice. I believe I have the manual. Thanks, Bob - Original Message - From: "Burt I. Weiner" To: Sent: Saturday, July 24, 2010 9:53 PM Subject: [time-nuts] HP-3586B Tunable Voltmeter... Bob, For dBm or Volts across 50 Ohms, I normally set it for 10K bridging and use a 50 Ohm terminating connector. 10K terminated by 50 Ohms is close to 49.75 Ohms, which is close enough for anything I need to do. I suppose if I really needed to get accurate, I'd take a file to a 50 Ohm resistor like we did in the good old days. I've never been sure why the 3586B always seems to be less expensive than the A version other than possibly because of the A being a 50 Ohm instrument. I have a pdf service manual for the A,B & C instruments. Do you need a copy for working on your B? What kind of problems does your B have? I've repaired a few and have a little knowledge in repairing them. Burt From: "Robert Benward" Subject: Re: [time-nuts] HP-3586B receiver... Burt I believe the voltmeter is calibrated for 75 ohms, not 50, otherwise they are very similar. You can apply a dB offset to correct for the measurement error, run the input at 10Kohms, and use a 50ohm feedthrough termination. I own both (the B is has problems now), but I use the voltage measurement capability extensively. The B is much cheaper on Ebay. Bob - Original Message - From: Burt I. Weiner Sent: Saturday, July 24, 2010 4:05 PM Subject: [time-nuts] HP-3586B receiver... I prefer the 3586-B version. I think it's more user friendly - once you get the hang of it, it does more. Burt I. Weiner Associates Broadcast Technical Services Glendale, California U.S.A. b...@att.net www.biwa.cc K6OQK ___ 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] Basic question regarding comparing two frequencies
> Thanks for the insight re the GPIB interface. I'm curious if any has any > insight as to a suitable usb or pci to GPIB interface module or card ? It > sounds as though other surplus test gear is likely to have a GPIB interface. I've been happy with the Prologix unit. I got mine through Sparkfun: http://www.sparkfun.com/commerce/product_info.php?products_id=549 It's USB to GPIB, but it uses one of the popular USB-serial chips so drivers should be easy to find. (if you don't have them already) That lets you talk to it, but you may have to write some low level code to do what you want. I'm happy with that stuff. Some people don't like it. > Thanks, I'm glad to hear I am on the right track. At some point it would > be nice to obtain a counter that can measure the drift of the time base in > the 5328A. The 5328A has a GPIB interface but as the display only varies > by a few counts I'm not inclined to track down a GPIB adapter just to plot > this.) Hopefully a newer counter would have a more generic interface. I'm not familiar with the 5328A. On the 5334B, you can get a two more digits via GPIB. For example: F +2.997105E+06 (The display only has 9 digits.) -- These are my opinions, not necessarily my employer's. I hate spam. ___ 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] Basic question regarding comparing two frequencies
Probably yes. There are also a number of lower cost instruments (just above consumer grade)like HF-VHF VNAs that implement much of the smarts in a PC on the market. As to high end instruments w/ USB or Ethernet, I'm not so sure. The USA is doing less and less hardware development, so instruments are not being bought in anything like the quantity as in the past. FWIW, -John == > J. Forster wrote: >> I very much doubt that the majority on this list have major govenmental >> or >> corporate funding and shop from the new Agilent catalog that just came >> in >> the mail. >> >> As a result, I'd guess almost all the commercial test gear in the >> posession of listers is from 1970 to 2000. That says GPIB and almost >> nothing else. A very few instruments did use dedicated ISA, LSI-11, or >> RS-232, but the numbers are tiny. >> >> The fact is that with GPIB you can cobble up a system to almost anything >> from simple to complex very quickly. > > > But over the next few years, I suspect you'll see more and more of it > coming onto the surplus market. My fond hope is that my daughter will > be able to capitalize on it. > > > > > > ___ 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] Basic question regarding comparing two frequencies
J. Forster wrote: I very much doubt that the majority on this list have major govenmental or corporate funding and shop from the new Agilent catalog that just came in the mail. As a result, I'd guess almost all the commercial test gear in the posession of listers is from 1970 to 2000. That says GPIB and almost nothing else. A very few instruments did use dedicated ISA, LSI-11, or RS-232, but the numbers are tiny. The fact is that with GPIB you can cobble up a system to almost anything from simple to complex very quickly. But over the next few years, I suspect you'll see more and more of it coming onto the surplus market. My fond hope is that my daughter will be able to capitalize on it. ___ 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] Basic question regarding comparing two frequencies
Check http://www.ko4bb.com/Test_Equipment/GPIB.php Didier KO4BB Sent from my BlackBerry Wireless thingy while I do other things... -Original Message- From: Mark Spencer Sender: time-nuts-boun...@febo.com Date: Sat, 24 Jul 2010 18:15:20 To: ; Reply-To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Basic question regarding comparing two frequencies Thanks for the insight re the GPIB interface. I'm curious if any has any insight as to a suitable usb or pci to GPIB interface module or card ? It sounds as though other surplus test gear is likely to have a GPIB interface. Regards Mark Spencer On Sat Jul 24th, 2010 6:40 PM EDT J. L. Trantham wrote: >I would agree. GPIB (aka HPIB) is ubiquitous and is a great place to start. >Unfortunately, I haven't gotten that up to the top of my 'to-do' list yet. >I have a computer, HP and National interface cards, cables, but no time to >find the software to make everything communicate yet. I think it has a lot >to do with the fact that I have relatively old HP equipment that is >relatively 'tongue-tied' but I think I will be able to figure it out once I >get the time. > >Certainly the right place to start though, IMO. > >Joe > >-Original Message- >From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On >Behalf Of J. Forster >Sent: Saturday, July 24, 2010 5:24 PM >To: Discussion of precise time and frequency measurement >Subject: Re: [time-nuts] Basic question regarding comparing two frequencies > >".. more generic interface." ?? > >The vast majority of professional test equipment has GPIB. Virtually >anything else is an "also ran". > >FWIW, > >-John > > > > >> Thanks, I'm glad to hear I am on the right track. At some point it would >> be >> nice to obtain a counter that can measure the drift of the time base in >> the >> 5328A. The 5328A has a GPIB interface but as the display only varies by a >> few >> counts I'm not inclined to track down a GPIB adapter just to plot this.) >> Hopefully a newer counter would have a more generic interface. >> >> Best regards >> Mark Spencer >> >> >> - Original Message >> From: J. L. Trantham >> To: Discussion of precise time and frequency measurement >> >> Sent: Sat, July 24, 2010 1:49:51 PM >> Subject: Re: [time-nuts] Basic question regarding comparing two >> frequencies >> >> Sounds about right. One cycle per 5 seconds or about 0.2 Hz difference. >> Therefore, 9,999,999.8 Hz. >> >> I would feed the GPSDO to trigger your scope and look at the output of the >> time base on one channel of the scope. You could also look at the GPSDO >> on >> the other channel. Then you could adjust your counter time base to >> 'freeze' >> the display. Probably good to 'align' the counter time base but for long >> term comparison, probably better to use a counter and plot the difference. >> >> Joe >> >> -Original Message- >> From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On >> Behalf Of Mark Spencer >> Sent: Saturday, July 24, 2010 12:29 PM >> To: time-nuts@febo.com >> Subject: [time-nuts] Basic question regarding comparing two frequencies >> >> Hello: >> >> Just for grins I decided to compare the frquency from my GPSDO to the time >> base >> in my 5328A counter. >> >> >> I connected the 10 mhz time base from the counter to channel A of my 100 >> Mhz >> >> scope, fed the 10 mhz signal from my GPSDO into Channel B and with a T >> adaptor >> also fed this signal into the input of the counter. I scope to trigger >> from >> Channel B. >> >> >> The drift betwen the two signals on the scope seems to match the error in >> the >> displayed frquency on the counter. (ie. if the counter shows .9998 it >> takes >> approx 5 seconds for the the wave form on channel A to slip a full cycle >> realitve to channel B.) >> >> >> Is this a reasonable approach or is there a better way to compare two >> frequencies using a scope ? >> >> Best regards >> Mark Spencer >> >> >> >>___ >> 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] HP-3586B Tunable Voltmeter...
Bob, For dBm or Volts across 50 Ohms, I normally set it for 10K bridging and use a 50 Ohm terminating connector. 10K terminated by 50 Ohms is close to 49.75 Ohms, which is close enough for anything I need to do. I suppose if I really needed to get accurate, I'd take a file to a 50 Ohm resistor like we did in the good old days. I've never been sure why the 3586B always seems to be less expensive than the A version other than possibly because of the A being a 50 Ohm instrument. I have a pdf service manual for the A,B & C instruments. Do you need a copy for working on your B? What kind of problems does your B have? I've repaired a few and have a little knowledge in repairing them. Burt From: "Robert Benward" Subject: Re: [time-nuts] HP-3586B receiver... Burt I believe the voltmeter is calibrated for 75 ohms, not 50, otherwise they are very similar. You can apply a dB offset to correct for the measurement error, run the input at 10Kohms, and use a 50ohm feedthrough termination. I own both (the B is has problems now), but I use the voltage measurement capability extensively. The B is much cheaper on Ebay. Bob - Original Message - From: Burt I. Weiner Sent: Saturday, July 24, 2010 4:05 PM Subject: [time-nuts] HP-3586B receiver... I prefer the 3586-B version. I think it's more user friendly - once you get the hang of it, it does more. Burt I. Weiner Associates Broadcast Technical Services Glendale, California U.S.A. b...@att.net www.biwa.cc K6OQK ___ 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] Basic question regarding comparing two frequencies
EDN magazine published a simple USB to GPIB design back in 2005, and someday I might build one up for myself. Hence this email is meant to be informational and not an endorsement. The original author has updated his design since then, check out the info and links at http://lpvo.fe.uni-lj.si/gpib/ where the original design is well documented for DIY and the updated version available as a "kit" if that interests you. Bob LaJeunesse From: Mark Spencer To: time-nuts@febo.com; j...@quik.com Sent: Sat, July 24, 2010 9:15:20 PM Subject: Re: [time-nuts] Basic question regarding comparing two frequencies Thanks for the insight re the GPIB interface. I'm curious if any has any insight as to a suitable usb or pci to GPIB interface module or card ? It sounds as though other surplus test gear is likely to have a GPIB interface. Regards Mark Spencer On Sat Jul 24th, 2010 6:40 PM EDT J. L. Trantham wrote: >I would agree. GPIB (aka HPIB) is ubiquitous and is a great place to start. >Unfortunately, I haven't gotten that up to the top of my 'to-do' list yet. >I have a computer, HP and National interface cards, cables, but no time to >find the software to make everything communicate yet. I think it has a lot >to do with the fact that I have relatively old HP equipment that is >relatively 'tongue-tied' but I think I will be able to figure it out once I >get the time. > >Certainly the right place to start though, IMO. > >Joe > >-Original Message- >From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On >Behalf Of J. Forster >Sent: Saturday, July 24, 2010 5:24 PM >To: Discussion of precise time and frequency measurement >Subject: Re: [time-nuts] Basic question regarding comparing two frequencies > >".. more generic interface." ?? > >The vast majority of professional test equipment has GPIB. Virtually >anything else is an "also ran". > >FWIW, > >-John > > > > >> Thanks, I'm glad to hear I am on the right track. At some point it would >> be >> nice to obtain a counter that can measure the drift of the time base in >> the >> 5328A. The 5328A has a GPIB interface but as the display only varies by a >> few >> counts I'm not inclined to track down a GPIB adapter just to plot this.) >> Hopefully a newer counter would have a more generic interface. >> >> Best regards >> Mark Spencer >> >> >> - Original Message >> From: J. L. Trantham >> To: Discussion of precise time and frequency measurement >> >> Sent: Sat, July 24, 2010 1:49:51 PM >> Subject: Re: [time-nuts] Basic question regarding comparing two >> frequencies >> >> Sounds about right. One cycle per 5 seconds or about 0.2 Hz difference. >> Therefore, 9,999,999.8 Hz. >> >> I would feed the GPSDO to trigger your scope and look at the output of the >> time base on one channel of the scope. You could also look at the GPSDO >> on >> the other channel. Then you could adjust your counter time base to >> 'freeze' >> the display. Probably good to 'align' the counter time base but for long >> term comparison, probably better to use a counter and plot the difference. >> >> Joe >> >> -Original Message- >> From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On >> Behalf Of Mark Spencer >> Sent: Saturday, July 24, 2010 12:29 PM >> To: time-nuts@febo.com >> Subject: [time-nuts] Basic question regarding comparing two frequencies >> >> Hello: >> >> Just for grins I decided to compare the frquency from my GPSDO to the time >> base >> in my 5328A counter. >> >> >> I connected the 10 mhz time base from the counter to channel A of my 100 >> Mhz >> >> scope, fed the 10 mhz signal from my GPSDO into Channel B and with a T >> adaptor >> also fed this signal into the input of the counter. I scope to trigger >> from >> Channel B. >> >> >> The drift betwen the two signals on the scope seems to match the error in >> the >> displayed frquency on the counter. (ie. if the counter shows .9998 it >> takes >> approx 5 seconds for the the wave form on channel A to slip a full cycle >> realitve to channel B.) >> >> >> Is this a reasonable approach or is there a better way to compare two >> frequencies using a scope ? >> >> Best regards >> Mark Spencer >> >> >> >> ___ >> 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] Basic question regarding comparing two frequencies
Thanks for the insight re the GPIB interface. I'm curious if any has any insight as to a suitable usb or pci to GPIB interface module or card ? It sounds as though other surplus test gear is likely to have a GPIB interface. Regards Mark Spencer On Sat Jul 24th, 2010 6:40 PM EDT J. L. Trantham wrote: >I would agree. GPIB (aka HPIB) is ubiquitous and is a great place to start. >Unfortunately, I haven't gotten that up to the top of my 'to-do' list yet. >I have a computer, HP and National interface cards, cables, but no time to >find the software to make everything communicate yet. I think it has a lot >to do with the fact that I have relatively old HP equipment that is >relatively 'tongue-tied' but I think I will be able to figure it out once I >get the time. > >Certainly the right place to start though, IMO. > >Joe > >-Original Message- >From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On >Behalf Of J. Forster >Sent: Saturday, July 24, 2010 5:24 PM >To: Discussion of precise time and frequency measurement >Subject: Re: [time-nuts] Basic question regarding comparing two frequencies > >".. more generic interface." ?? > >The vast majority of professional test equipment has GPIB. Virtually >anything else is an "also ran". > >FWIW, > >-John > > > > >> Thanks, I'm glad to hear I am on the right track. At some point it would >> be >> nice to obtain a counter that can measure the drift of the time base in >> the >> 5328A. The 5328A has a GPIB interface but as the display only varies by a >> few >> counts I'm not inclined to track down a GPIB adapter just to plot this.) >> Hopefully a newer counter would have a more generic interface. >> >> Best regards >> Mark Spencer >> >> >> - Original Message >> From: J. L. Trantham >> To: Discussion of precise time and frequency measurement >> >> Sent: Sat, July 24, 2010 1:49:51 PM >> Subject: Re: [time-nuts] Basic question regarding comparing two >> frequencies >> >> Sounds about right. One cycle per 5 seconds or about 0.2 Hz difference. >> Therefore, 9,999,999.8 Hz. >> >> I would feed the GPSDO to trigger your scope and look at the output of the >> time base on one channel of the scope. You could also look at the GPSDO >> on >> the other channel. Then you could adjust your counter time base to >> 'freeze' >> the display. Probably good to 'align' the counter time base but for long >> term comparison, probably better to use a counter and plot the difference. >> >> Joe >> >> -Original Message- >> From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On >> Behalf Of Mark Spencer >> Sent: Saturday, July 24, 2010 12:29 PM >> To: time-nuts@febo.com >> Subject: [time-nuts] Basic question regarding comparing two frequencies >> >> Hello: >> >> Just for grins I decided to compare the frquency from my GPSDO to the time >> base >> in my 5328A counter. >> >> >> I connected the 10 mhz time base from the counter to channel A of my 100 >> Mhz >> >> scope, fed the 10 mhz signal from my GPSDO into Channel B and with a T >> adaptor >> also fed this signal into the input of the counter. I scope to trigger >> from >> Channel B. >> >> >> The drift betwen the two signals on the scope seems to match the error in >> the >> displayed frquency on the counter. (ie. if the counter shows .9998 it >> takes >> approx 5 seconds for the the wave form on channel A to slip a full cycle >> realitve to channel B.) >> >> >> Is this a reasonable approach or is there a better way to compare two >> frequencies using a scope ? >> >> Best regards >> Mark Spencer >> >> >> >> ___ >> 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. ___ 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] Basic question regarding comparing two frequencies
I very much doubt that the majority on this list have major govenmental or corporate funding and shop from the new Agilent catalog that just came in the mail. As a result, I'd guess almost all the commercial test gear in the posession of listers is from 1970 to 2000. That says GPIB and almost nothing else. A very few instruments did use dedicated ISA, LSI-11, or RS-232, but the numbers are tiny. The fact is that with GPIB you can cobble up a system to almost anything from simple to complex very quickly. YMMV, -John === > J. Forster wrote: >> ".. more generic interface." ?? >> >> The vast majority of professional test equipment has GPIB. Virtually >> anything else is an "also ran". >> >> FWIW, >> >> -John >> >> > > these days, ethernet and USB are becoming more popular. My own > preference is Ethernet and I long for the day when I can ditch the last > GPIB cable (and the stacking connectors where you always seem to need > the one on the bottom of the stack) Yes, GPIB provides some clever > triggering across the interface, useful for things like sweepers and > vector voltmeters, but I suspect that it's not much used these days.. > rather you wind up sending binary or ascii strings across the interface. > > ___ 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] Basic question regarding comparing two frequencies
Speaking of which, should have or stumble a gpib for said 5328a, I'm looking for one to go in my counter. Thanks, Bob On 7/24/10, Mark Spencer wrote: > Thanks, I'm glad to hear I am on the right track. At some point it would > be > nice to obtain a counter that can measure the drift of the time base in the > 5328A. The 5328A has a GPIB interface but as the display only varies by a > few > counts I'm not inclined to track down a GPIB adapter just to plot this.) > Hopefully a newer counter would have a more generic interface. > > Best regards > Mark Spencer > > > - Original Message > From: J. L. Trantham > To: Discussion of precise time and frequency measurement > > Sent: Sat, July 24, 2010 1:49:51 PM > Subject: Re: [time-nuts] Basic question regarding comparing two frequencies > > Sounds about right. One cycle per 5 seconds or about 0.2 Hz difference. > Therefore, 9,999,999.8 Hz. > > I would feed the GPSDO to trigger your scope and look at the output of the > time base on one channel of the scope. You could also look at the GPSDO on > the other channel. Then you could adjust your counter time base to 'freeze' > the display. Probably good to 'align' the counter time base but for long > term comparison, probably better to use a counter and plot the difference. > > Joe > > -Original Message- > From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On > Behalf Of Mark Spencer > Sent: Saturday, July 24, 2010 12:29 PM > To: time-nuts@febo.com > Subject: [time-nuts] Basic question regarding comparing two frequencies > > Hello: > > Just for grins I decided to compare the frquency from my GPSDO to the time > base > in my 5328A counter. > > > I connected the 10 mhz time base from the counter to channel A of my 100 Mhz > > scope, fed the 10 mhz signal from my GPSDO into Channel B and with a T > adaptor > also fed this signal into the input of the counter. I scope to trigger > from > Channel B. > > > The drift betwen the two signals on the scope seems to match the error in > the > displayed frquency on the counter. (ie. if the counter shows .9998 it > takes > approx 5 seconds for the the wave form on channel A to slip a full cycle > realitve to channel B.) > > > Is this a reasonable approach or is there a better way to compare two > frequencies using a scope ? > > Best regards > Mark Spencer > > > > ___ > 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] Basic question regarding comparing two frequencies
J. Forster wrote: ".. more generic interface." ?? The vast majority of professional test equipment has GPIB. Virtually anything else is an "also ran". FWIW, -John these days, ethernet and USB are becoming more popular. My own preference is Ethernet and I long for the day when I can ditch the last GPIB cable (and the stacking connectors where you always seem to need the one on the bottom of the stack) Yes, GPIB provides some clever triggering across the interface, useful for things like sweepers and vector voltmeters, but I suspect that it's not much used these days.. rather you wind up sending binary or ascii strings across the interface. ___ 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] Basic question regarding comparing two frequencies
If you have NI card(s) it is easy. National makes the simple SW available for free. Last time I looked there is a console command line utility and a VB and C interfaces. Labview is a different story. A new version is $$$. You can sometimes find older versions on eBay. Some versions are PW keyed, so be careful. NI has a stunning selection of virtual instruments for free, I think. The HP-IB cards are much more problematic. AFAIK, there is little to no SW support. I have a couple, but only because they are required to run a specific instrument (a Laser Interferometer) with a PC and HP system SW. There are also 2nd source GPIB cards (Prologix, etc). The SW support is spotty, although I'm told that Prologix is pretty good. FWIW, -John == > I would agree. GPIB (aka HPIB) is ubiquitous and is a great place to > start. > Unfortunately, I haven't gotten that up to the top of my 'to-do' list yet. > I have a computer, HP and National interface cards, cables, but no time to > find the software to make everything communicate yet. I think it has a > lot > to do with the fact that I have relatively old HP equipment that is > relatively 'tongue-tied' but I think I will be able to figure it out once > I > get the time. > > Certainly the right place to start though, IMO. > > Joe > > -Original Message- > From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On > Behalf Of J. Forster > Sent: Saturday, July 24, 2010 5:24 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Basic question regarding comparing two > frequencies > > ".. more generic interface." ?? > > The vast majority of professional test equipment has GPIB. Virtually > anything else is an "also ran". > > FWIW, > > -John > > > > >> Thanks, I'm glad to hear I am on the right track. At some point >> it would >> be >> nice to obtain a counter that can measure the drift of the time base in >> the >> 5328A. The 5328A has a GPIB interface but as the display only varies by >> a >> few >> counts I'm not inclined to track down a GPIB adapter just to plot >> this.) >> Hopefully a newer counter would have a more generic interface. >> >> Best regards >> Mark Spencer >> >> >> - Original Message >> From: J. L. Trantham >> To: Discussion of precise time and frequency measurement >> >> Sent: Sat, July 24, 2010 1:49:51 PM >> Subject: Re: [time-nuts] Basic question regarding comparing two >> frequencies >> >> Sounds about right. One cycle per 5 seconds or about 0.2 Hz difference. >> Therefore, 9,999,999.8 Hz. >> >> I would feed the GPSDO to trigger your scope and look at the output of >> the >> time base on one channel of the scope. You could also look at the GPSDO >> on >> the other channel. Then you could adjust your counter time base to >> 'freeze' >> the display. Probably good to 'align' the counter time base but for >> long >> term comparison, probably better to use a counter and plot the >> difference. >> >> Joe >> >> -Original Message- >> From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On >> Behalf Of Mark Spencer >> Sent: Saturday, July 24, 2010 12:29 PM >> To: time-nuts@febo.com >> Subject: [time-nuts] Basic question regarding comparing two frequencies >> >> Hello: >> >> Just for grins I decided to compare the frquency from my GPSDO to the >> time >> base >> in my 5328A counter. >> >> >> I connected the 10 mhz time base from the counter to channel A of my 100 >> Mhz >> >> scope, fed the 10 mhz signal from my GPSDO into Channel B and with a T >> adaptor >> also fed this signal into the input of the counter. I scope to >> trigger >> from >> Channel B. >> >> >> The drift betwen the two signals on the scope seems to match the error >> in >> the >> displayed frquency on the counter. (ie. if the counter shows .9998 >> it >> takes >> approx 5 seconds for the the wave form on channel A to slip a full cycle >> realitve to channel B.) >> >> >> Is this a reasonable approach or is there a better way to compare two >> frequencies using a scope ? >> >> Best regards >> Mark Spencer >> >> >> >> ___ >> 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/list
Re: [time-nuts] HP-3586B receiver...
Burt I believe the voltmeter is calibrated for 75 ohms, not 50, otherwise they are very similar. You can apply a dB offset to correct for the measurement error, run the input at 10Kohms, and use a 50ohm feedthrough termination. I own both (the B is has problems now), but I use the voltage measurement capability extensively. The B is much cheaper on Ebay. Bob - Original Message - From: Burt I. Weiner To: time-nuts@febo.com Sent: Saturday, July 24, 2010 4:05 PM Subject: [time-nuts] HP-3586B receiver... I prefer the 3586-B version. I think it's more user friendly - once you get the hang of it, it does more. You can get off-the -shelf adaptors for the weird telco connectors to BNC for about $20, but it's simpler to just change out the connectors to BNC. The input module is a plug-in box. Remove six front panel screws, swing front panel out of the way, unplug the input module, replace connector, plug in the input module, look for screws you just had, replace just-lost screws, try again, and Voilla, normal connectors. The detection is only upper or lower sideband. Mine is GPS referenced and I use it for AM, PSK-31, RTTY, as well for FMT's. I live within 4 miles to two 50 KW AM stations and Have never had a problem when using my 210' Inverted-V. The selectable bandwidths with common options are: 3.1 kHz, 400 Hz, and 20 Hz. Marv Collins, W6OQI came over to our home about 3 years ago to look at the one I had at the time (I now have two of the B's). He said he doesn't know how he'd ever use one. Marv now has two of the B's. Burt, K6OQK At 12:32 PM 7/24/2010, time-nuts-requ...@febo.com wrote >Subject: Re: [time-nuts] A Highly-Accurate and Stable SDR-IQ Using > GPS-DO and DFS >To: "paul swed" >Cc: Discussion of precise time and frequency measurement > >Message-ID: <58923.12.6.201.2.1279990884.squir...@popaccts.quikus.com> >Content-Type: text/plain;charset=iso-8859-1 > >Oops. Yes, typo. Sorry. > >I don't know about the A version but the and C are essentially identical >except the B used wierd Telco connectors. An new adapter might cost as >much as you'd pay for the receiver. > >Their shortfall is the demodulation options are limited, but they do a >wonderful job of measuring carrier frequency. > >Best, > >-John Burt I. Weiner Associates Broadcast Technical Services Glendale, California U.S.A. b...@att.net www.biwa.cc K6OQK ___ 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] Basic question regarding comparing two frequencies
I would agree. GPIB (aka HPIB) is ubiquitous and is a great place to start. Unfortunately, I haven't gotten that up to the top of my 'to-do' list yet. I have a computer, HP and National interface cards, cables, but no time to find the software to make everything communicate yet. I think it has a lot to do with the fact that I have relatively old HP equipment that is relatively 'tongue-tied' but I think I will be able to figure it out once I get the time. Certainly the right place to start though, IMO. Joe -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of J. Forster Sent: Saturday, July 24, 2010 5:24 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Basic question regarding comparing two frequencies ".. more generic interface." ?? The vast majority of professional test equipment has GPIB. Virtually anything else is an "also ran". FWIW, -John > Thanks, I'm glad to hear I am on the right track. At some point it would > be > nice to obtain a counter that can measure the drift of the time base in > the > 5328A. The 5328A has a GPIB interface but as the display only varies by a > few > counts I'm not inclined to track down a GPIB adapter just to plot this.) > Hopefully a newer counter would have a more generic interface. > > Best regards > Mark Spencer > > > - Original Message > From: J. L. Trantham > To: Discussion of precise time and frequency measurement > > Sent: Sat, July 24, 2010 1:49:51 PM > Subject: Re: [time-nuts] Basic question regarding comparing two > frequencies > > Sounds about right. One cycle per 5 seconds or about 0.2 Hz difference. > Therefore, 9,999,999.8 Hz. > > I would feed the GPSDO to trigger your scope and look at the output of the > time base on one channel of the scope. You could also look at the GPSDO > on > the other channel. Then you could adjust your counter time base to > 'freeze' > the display. Probably good to 'align' the counter time base but for long > term comparison, probably better to use a counter and plot the difference. > > Joe > > -Original Message- > From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On > Behalf Of Mark Spencer > Sent: Saturday, July 24, 2010 12:29 PM > To: time-nuts@febo.com > Subject: [time-nuts] Basic question regarding comparing two frequencies > > Hello: > > Just for grins I decided to compare the frquency from my GPSDO to the time > base > in my 5328A counter. > > > I connected the 10 mhz time base from the counter to channel A of my 100 > Mhz > > scope, fed the 10 mhz signal from my GPSDO into Channel B and with a T > adaptor > also fed this signal into the input of the counter. I scope to trigger > from > Channel B. > > > The drift betwen the two signals on the scope seems to match the error in > the > displayed frquency on the counter. (ie. if the counter shows .9998 it > takes > approx 5 seconds for the the wave form on channel A to slip a full cycle > realitve to channel B.) > > > Is this a reasonable approach or is there a better way to compare two > frequencies using a scope ? > > Best regards > Mark Spencer > > > > ___ > 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] Basic question regarding comparing two frequencies
".. more generic interface." ?? The vast majority of professional test equipment has GPIB. Virtually anything else is an "also ran". FWIW, -John > Thanks, I'm glad to hear I am on the right track. At some point it would > be > nice to obtain a counter that can measure the drift of the time base in > the > 5328A. The 5328A has a GPIB interface but as the display only varies by a > few > counts I'm not inclined to track down a GPIB adapter just to plot this.) > Hopefully a newer counter would have a more generic interface. > > Best regards > Mark Spencer > > > - Original Message > From: J. L. Trantham > To: Discussion of precise time and frequency measurement > > Sent: Sat, July 24, 2010 1:49:51 PM > Subject: Re: [time-nuts] Basic question regarding comparing two > frequencies > > Sounds about right. One cycle per 5 seconds or about 0.2 Hz difference. > Therefore, 9,999,999.8 Hz. > > I would feed the GPSDO to trigger your scope and look at the output of the > time base on one channel of the scope. You could also look at the GPSDO > on > the other channel. Then you could adjust your counter time base to > 'freeze' > the display. Probably good to 'align' the counter time base but for long > term comparison, probably better to use a counter and plot the difference. > > Joe > > -Original Message- > From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On > Behalf Of Mark Spencer > Sent: Saturday, July 24, 2010 12:29 PM > To: time-nuts@febo.com > Subject: [time-nuts] Basic question regarding comparing two frequencies > > Hello: > > Just for grins I decided to compare the frquency from my GPSDO to the time > base > in my 5328A counter. > > > I connected the 10 mhz time base from the counter to channel A of my 100 > Mhz > > scope, fed the 10 mhz signal from my GPSDO into Channel B and with a T > adaptor > also fed this signal into the input of the counter. I scope to trigger > from > Channel B. > > > The drift betwen the two signals on the scope seems to match the error in > the > displayed frquency on the counter. (ie. if the counter shows .9998 it > takes > approx 5 seconds for the the wave form on channel A to slip a full cycle > realitve to channel B.) > > > Is this a reasonable approach or is there a better way to compare two > frequencies using a scope ? > > Best regards > Mark Spencer > > > > ___ > 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] Symmetricom X72
To Bob and Stan (W1LE),
[p.s. But not just to you two alone]
Why complicate the answers to Heathkid (now Brice KA8MAV) with a bunch of
different directions that should only be decided after one gains enough
knowledge and understanding (they are not the same) to properly grasp the
subject matter ? ? ? ?
Clearly Heathkid needs some guidance. The form should be to start out with the
very basics and get his feet on the ground. He already has three (3) Rb
sources that should keep him busy for quite some time. However, his counter is
really junk from a lab point of view. Nonetheless, even it can be useful if it
is understood how to apply it after understanding its limitations.
What Heathkid needs to understand is it is not about equipment. It is all
about how to measure and account for errors and unknowns. Actually, quite a
daunting task depending upon the level of achievement.
I agree he needs some kind of external reference and I agree the Trimble
Thunderbolt (Tbolt) would be the right item for his true reference. Even the
Tbolt has its issues that need to be understood.
He will also need a method of comparison. The oscilloscope is a good start
but very tedious. Here Burt's project would help him a lot when Burt gets it
done. I guess he is close. I guess, also, the PICTIC II would fit the bill
after he understands what it is.
Still he needs to understand how to apply and use this stuff. Confusing him
with suggesting all of the different Rb sources available is only making him
think a better one { relative statement } would be the answer which is not
true. His FEI-5680's are so much better for his particular level, it is not
even funny.
What has not been asked of him is what are his goals and intentions. If it is
to just say you have an atomic frequency reference, then sit the FEI-5680 on
the coffee table; job done. One cannot be properly guided if the goals are
unknown.
BillWB6BNQ
Bob Camp wrote:
> Hi
>
> The only way to be sure of what's going on is to have several (hopefully)
> accurate references. With at least three you can begin to guess how good they
> are.
>
> The TBolt is different from the Rb in a couple of regards:
>
> 1) It's short term stability isn't as good when locked tightly to the GPS.
> 2) It's long term stability is much better than the Rb when it's locked.
> 3) It's easier to tell what's happening with it if you hook up a PC and the
> Lady Heather (free) program.
>
> The Rb will need a couple of things to make it play right:
>
> 1) It's got to have a pretty good heat sink on it. An 8 x 10" piece of 1/4"
> aluminum is a reasonable start
> 2) It's got to be run for a while (possibly 24 hours) before it will be stable
> 3) You need to watch the lock, and lamp voltages to be sure it's not doing
> something crazy.
>
> My recommendation based on cost is the Efratom LPRO for a cheap Rb. They are
> in the ~$60 range and seem to work pretty well.
>
> Setup wise, I would get a TBolt in addition to the Rb. You need something to
> calibrate the Rb (and your counter TCXO) against. Both are "secondary"
> standards. They (unlike a Cesium) are adjusted to match a known good
> reference.
>
> Once you have the Rb and the TBolt, next step is up to you. Cesium is always
> an alternative, so's a Hydrogen Maser
>
> Bob
>
> On Jul 24, 2010, at 3:32 PM, Heathkid wrote:
>
> > Hello Bob,
> >
> > What would you recommend? I already have three FE-5680A Rb standards
> > (which I'm quickly learning likely aren't worth the powder to blow them to
> > (*insert your own word here*). Okay, that was probably my first mistake
> > (thoughts?).
> >
> > My frequency counter is one I built from a kit from aade.com that has the
> > TCXO option (although I had to tweak it myself so I have NO idea how close
> > it is to any accuracy or precision). I have access to some really nice HP
> > counters at work so that's my next step is to try one of those. My DFD4
> > measured the output of one of my 5680A's to 10.000.007 MHz after about a 10
> > minute warm-up. I don't know which one is off. Reading the specs on the
> > 5680A's before I bought them looked like they were pretty decent. I'm
> > learning...
> >
> > So, what "reasonably priced" Rb standard would you recommend?
> >
> > Should my next step in this process be a Trimble Thunderbolt? Am I
> > starting over?
> >
> > Thanks...
> >
> > - Original Message - From: "Bob Camp"
> > To: "Discussion of precise time and frequency measurement"
> >
> > Sent: Saturday, July 24, 2010 9:31 AM
> > Subject: Re: [time-nuts] Symmetricom X72
> >
> >
> >> Hi
> >>
> >> At least looking at the spec sheet it's not really very impressive.
> >>
> >> Bob
> >>
> >>
> >> On Jul 23, 2010, at 11:06 PM, Heathkid wrote:
> >>
> >>> Hello. Does anyone have any experience with the Symmetricom X72?
> >>>
> >>> Thanks...
> >>>
> >>> ___
> >>> time-nuts mailing list -- time-nuts@
Re: [time-nuts] Basic question regarding comparing two frequencies
Thanks, I'm glad to hear I am on the right track. At some point it would be nice to obtain a counter that can measure the drift of the time base in the 5328A. The 5328A has a GPIB interface but as the display only varies by a few counts I'm not inclined to track down a GPIB adapter just to plot this.) Hopefully a newer counter would have a more generic interface. Best regards Mark Spencer - Original Message From: J. L. Trantham To: Discussion of precise time and frequency measurement Sent: Sat, July 24, 2010 1:49:51 PM Subject: Re: [time-nuts] Basic question regarding comparing two frequencies Sounds about right. One cycle per 5 seconds or about 0.2 Hz difference. Therefore, 9,999,999.8 Hz. I would feed the GPSDO to trigger your scope and look at the output of the time base on one channel of the scope. You could also look at the GPSDO on the other channel. Then you could adjust your counter time base to 'freeze' the display. Probably good to 'align' the counter time base but for long term comparison, probably better to use a counter and plot the difference. Joe -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Mark Spencer Sent: Saturday, July 24, 2010 12:29 PM To: time-nuts@febo.com Subject: [time-nuts] Basic question regarding comparing two frequencies Hello: Just for grins I decided to compare the frquency from my GPSDO to the time base in my 5328A counter. I connected the 10 mhz time base from the counter to channel A of my 100 Mhz scope, fed the 10 mhz signal from my GPSDO into Channel B and with a T adaptor also fed this signal into the input of the counter. I scope to trigger from Channel B. The drift betwen the two signals on the scope seems to match the error in the displayed frquency on the counter. (ie. if the counter shows .9998 it takes approx 5 seconds for the the wave form on channel A to slip a full cycle realitve to channel B.) Is this a reasonable approach or is there a better way to compare two frequencies using a scope ? Best regards Mark Spencer ___ 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] Cesium Reference
Anyone around here close to central Indiana with a Cesium Reference? :) 73 Brice KA8MAV ___ 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] Symmetricom X72
Bob, so you're saying the Efratom LPRO is better than the three FE-5680A's I already have? Sounds like I do need a TBolt anyway. - Original Message - From: "Bob Camp" To: "Discussion of precise time and frequency measurement" Sent: Saturday, July 24, 2010 5:20 PM Subject: Re: [time-nuts] Symmetricom X72 Hi The only way to be sure of what's going on is to have several (hopefully) accurate references. With at least three you can begin to guess how good they are. The TBolt is different from the Rb in a couple of regards: 1) It's short term stability isn't as good when locked tightly to the GPS. 2) It's long term stability is much better than the Rb when it's locked. 3) It's easier to tell what's happening with it if you hook up a PC and the Lady Heather (free) program. The Rb will need a couple of things to make it play right: 1) It's got to have a pretty good heat sink on it. An 8 x 10" piece of 1/4" aluminum is a reasonable start 2) It's got to be run for a while (possibly 24 hours) before it will be stable 3) You need to watch the lock, and lamp voltages to be sure it's not doing something crazy. My recommendation based on cost is the Efratom LPRO for a cheap Rb. They are in the ~$60 range and seem to work pretty well. Setup wise, I would get a TBolt in addition to the Rb. You need something to calibrate the Rb (and your counter TCXO) against. Both are "secondary" standards. They (unlike a Cesium) are adjusted to match a known good reference. Once you have the Rb and the TBolt, next step is up to you. Cesium is always an alternative, so's a Hydrogen Maser Bob On Jul 24, 2010, at 3:32 PM, Heathkid wrote: Hello Bob, What would you recommend? I already have three FE-5680A Rb standards (which I'm quickly learning likely aren't worth the powder to blow them to (*insert your own word here*). Okay, that was probably my first mistake (thoughts?). My frequency counter is one I built from a kit from aade.com that has the TCXO option (although I had to tweak it myself so I have NO idea how close it is to any accuracy or precision). I have access to some really nice HP counters at work so that's my next step is to try one of those. My DFD4 measured the output of one of my 5680A's to 10.000.007 MHz after about a 10 minute warm-up. I don't know which one is off. Reading the specs on the 5680A's before I bought them looked like they were pretty decent. I'm learning... So, what "reasonably priced" Rb standard would you recommend? Should my next step in this process be a Trimble Thunderbolt? Am I starting over? Thanks... - Original Message - From: "Bob Camp" To: "Discussion of precise time and frequency measurement" Sent: Saturday, July 24, 2010 9:31 AM Subject: Re: [time-nuts] Symmetricom X72 Hi At least looking at the spec sheet it's not really very impressive. Bob On Jul 23, 2010, at 11:06 PM, Heathkid wrote: Hello. Does anyone have any experience with the Symmetricom X72? Thanks... ___ 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] GR 1115B
Hi I have (thanks to a kind fellow list member) obtained a manual scan for the 115B Thanks! Bob On Jul 24, 2010, at 9:38 AM, Bob Camp wrote: > Hi > > My impression is that a lot of these guys put up a list of "everything and > anything on the planet" so the search engines find them. > > Still no luck on a free download manual. I may actually have to buy the GR > cdrom. > > Bob > > > On Jul 24, 2010, at 4:53 AM, K. Szeker wrote: > >> Sorry Bob, >> but the home addresse is working: >> http://www.imltest.com/ >> I found a very long listing on "inventory" yesterday, it was me only not >> full clear if its a real listing of "manual s to have" or they does serve >> repairing for the mentioned types... >> K. >> >> 2010/7/24 K. Szeker >> >>> Hi Bob, >>> >>> Raeser service repairs it_hopefuly have some documentations too? >>> http://www.raeservices.com/product-detail.asp?search=67241 >>> Seems; they have a manual too? http://www.imltest.com/inventory. >>> >> >>> Karesz >>> >>> 2010/7/24 Bob Camp >>> >>> Hi A GR 1115B seems to be headed this way. I have no idea what condition it's in. About all I have been able to find is the GR news article on the unit from 1961(?). Does anybody have a schematic or manual? Thanks! Bob ___ 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] Symmetricom X72
Hi The only way to be sure of what's going on is to have several (hopefully) accurate references. With at least three you can begin to guess how good they are. The TBolt is different from the Rb in a couple of regards: 1) It's short term stability isn't as good when locked tightly to the GPS. 2) It's long term stability is much better than the Rb when it's locked. 3) It's easier to tell what's happening with it if you hook up a PC and the Lady Heather (free) program. The Rb will need a couple of things to make it play right: 1) It's got to have a pretty good heat sink on it. An 8 x 10" piece of 1/4" aluminum is a reasonable start 2) It's got to be run for a while (possibly 24 hours) before it will be stable 3) You need to watch the lock, and lamp voltages to be sure it's not doing something crazy. My recommendation based on cost is the Efratom LPRO for a cheap Rb. They are in the ~$60 range and seem to work pretty well. Setup wise, I would get a TBolt in addition to the Rb. You need something to calibrate the Rb (and your counter TCXO) against. Both are "secondary" standards. They (unlike a Cesium) are adjusted to match a known good reference. Once you have the Rb and the TBolt, next step is up to you. Cesium is always an alternative, so's a Hydrogen Maser Bob On Jul 24, 2010, at 3:32 PM, Heathkid wrote: > Hello Bob, > > What would you recommend? I already have three FE-5680A Rb standards (which > I'm quickly learning likely aren't worth the powder to blow them to (*insert > your own word here*). Okay, that was probably my first mistake (thoughts?). > > My frequency counter is one I built from a kit from aade.com that has the > TCXO option (although I had to tweak it myself so I have NO idea how close it > is to any accuracy or precision). I have access to some really nice HP > counters at work so that's my next step is to try one of those. My DFD4 > measured the output of one of my 5680A's to 10.000.007 MHz after about a 10 > minute warm-up. I don't know which one is off. Reading the specs on the > 5680A's before I bought them looked like they were pretty decent. I'm > learning... > > So, what "reasonably priced" Rb standard would you recommend? > > Should my next step in this process be a Trimble Thunderbolt? Am I starting > over? > > Thanks... > > - Original Message - From: "Bob Camp" > To: "Discussion of precise time and frequency measurement" > > Sent: Saturday, July 24, 2010 9:31 AM > Subject: Re: [time-nuts] Symmetricom X72 > > >> Hi >> >> At least looking at the spec sheet it's not really very impressive. >> >> Bob >> >> >> On Jul 23, 2010, at 11:06 PM, Heathkid wrote: >> >>> Hello. Does anyone have any experience with the Symmetricom X72? >>> >>> Thanks... >>> >>> ___ >>> 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] Basic question regarding comparing two frequencies
Sounds about right. One cycle per 5 seconds or about 0.2 Hz difference. Therefore, 9,999,999.8 Hz. I would feed the GPSDO to trigger your scope and look at the output of the time base on one channel of the scope. You could also look at the GPSDO on the other channel. Then you could adjust your counter time base to 'freeze' the display. Probably good to 'align' the counter time base but for long term comparison, probably better to use a counter and plot the difference. Joe -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Mark Spencer Sent: Saturday, July 24, 2010 12:29 PM To: time-nuts@febo.com Subject: [time-nuts] Basic question regarding comparing two frequencies Hello: Just for grins I decided to compare the frquency from my GPSDO to the time base in my 5328A counter. I connected the 10 mhz time base from the counter to channel A of my 100 Mhz scope, fed the 10 mhz signal from my GPSDO into Channel B and with a T adaptor also fed this signal into the input of the counter. I scope to trigger from Channel B. The drift betwen the two signals on the scope seems to match the error in the displayed frquency on the counter. (ie. if the counter shows .9998 it takes approx 5 seconds for the the wave form on channel A to slip a full cycle realitve to channel B.) Is this a reasonable approach or is there a better way to compare two frequencies using a scope ? Best regards Mark Spencer ___ 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] Symmetricom X72
The Trimble Thunderbolt GPS/DOs have been on a nice learning curve. Lady Heather helps alot to understand what is going on. Checking and calibrating your freq counter to the stuff you have at work is a great idea. Just keep in mind the basic accuracy of the aade stuff, after you get back home. For my 10 GHz transverter I use a externally boxed up ISOTEMP 10 MHz xtal bases OCXO with voltage control. Before a radio contest I will warm up the OCXO for a few days, then I measure it with a freq counter using the GPSDO as reference. Adjusting as needed. I do not think you can go wrong with a Trimble T'Bolt. Cost effective fun. Stan, W1LE On 7/24/2010 3:32 PM, Heathkid wrote: Hello Bob, What would you recommend? I already have three FE-5680A Rb standards (which I'm quickly learning likely aren't worth the powder to blow them to (*insert your own word here*). Okay, that was probably my first mistake (thoughts?). My frequency counter is one I built from a kit from aade.com that has the TCXO option (although I had to tweak it myself so I have NO idea how close it is to any accuracy or precision). I have access to some really nice HP counters at work so that's my next step is to try one of those. My DFD4 measured the output of one of my 5680A's to 10.000.007 MHz after about a 10 minute warm-up. I don't know which one is off. Reading the specs on the 5680A's before I bought them looked like they were pretty decent. I'm learning... So, what "reasonably priced" Rb standard would you recommend? Should my next step in this process be a Trimble Thunderbolt? Am I starting over? Thanks... - Original Message - From: "Bob Camp" To: "Discussion of precise time and frequency measurement" Sent: Saturday, July 24, 2010 9:31 AM Subject: Re: [time-nuts] Symmetricom X72 Hi At least looking at the spec sheet it's not really very impressive. Bob On Jul 23, 2010, at 11:06 PM, Heathkid wrote: Hello. Does anyone have any experience with the Symmetricom X72? Thanks... ___ 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] Symmetricom X72
On 07/24/2010 09:32 PM, Heathkid wrote: Hello Bob, What would you recommend? I already have three FE-5680A Rb standards (which I'm quickly learning likely aren't worth the powder to blow them to (*insert your own word here*). Okay, that was probably my first mistake (thoughts?). My frequency counter is one I built from a kit from aade.com that has the TCXO option (although I had to tweak it myself so I have NO idea how close it is to any accuracy or precision). I have access to some really nice HP counters at work so that's my next step is to try one of those. My DFD4 measured the output of one of my 5680A's to 10.000.007 MHz after about a 10 minute warm-up. I don't know which one is off. Reading the specs on the 5680A's before I bought them looked like they were pretty decent. I'm learning... It's the TCXO in the DFD4 which may "only" 7E-7 off. The DFD4 isn't the right tool for measuring rubidiums with. Neat and all, it is not as good as needed. You need to get some better counter. So, what "reasonably priced" Rb standard would you recommend? Should my next step in this process be a Trimble Thunderbolt? Am I starting over? Thanks... A Thunderbolt would be a nice addition... but do keep the 5680s. I can get them of your hands if you really need to... but that should be a hint to you... Thunderbolt and some better counter is what you need. There are many counters which should be a good step in the right direction for you. I still use my HP5335A despite I have much better gear around. 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] Symmetricom X72
Heathkid, You got to be kidding ? I am guessing, from your comments, that you need to do a bunch more reading and pondering on the subjects of stability, accuracy and making those measurements. Especially before tossing the FEI-5680's in the trash. The FEI-5680A is a nice unit, you just have to understand what you have and how to apply it. Assuming that the FEI-5680 is working correctly, it will be more stable then most crystal oscillators found in the all but the very higher quality frequency counters. In comparison to your TCXO, the FEI-5680 would be 3 orders of magnitude (i.e., 3 more decimal places or a 1000 times) more stable. And likely a hell of a lot closer to the proper reference too. Until you have a measurement system that is known to be more accurate then the FEI-5680, there is no way to say it is a mistake. So, two primary components are at hand here; first being stability and the second being accuracy. Even if it is not SPOT on accurate with a world reference does not make it UN-usable as stability would be the more sought after parameter in any case. So, I disagree with your premise, BillWB6BNQ Heathkid wrote: > Hello Bob, > > What would you recommend? I already have three FE-5680A Rb standards (which > I'm quickly learning likely aren't worth the powder to blow them to (*insert > your own word here*). Okay, that was probably my first mistake (thoughts?). > > My frequency counter is one I built from a kit from aade.com that has the > TCXO option (although I had to tweak it myself so I have NO idea how close > it is to any accuracy or precision). I have access to some really nice HP > counters at work so that's my next step is to try one of those. My DFD4 > measured the output of one of my 5680A's to 10.000.007 MHz after about a 10 > minute warm-up. I don't know which one is off. Reading the specs on the > 5680A's before I bought them looked like they were pretty decent. I'm > learning... > > So, what "reasonably priced" Rb standard would you recommend? > > Should my next step in this process be a Trimble Thunderbolt? Am I starting > over? > > Thanks... > > - Original Message - > From: "Bob Camp" > To: "Discussion of precise time and frequency measurement" > > Sent: Saturday, July 24, 2010 9:31 AM > Subject: Re: [time-nuts] Symmetricom X72 > > > Hi > > > > At least looking at the spec sheet it's not really very impressive. > > > > Bob > > > > > > On Jul 23, 2010, at 11:06 PM, Heathkid wrote: > > > >> Hello. Does anyone have any experience with the Symmetricom X72? > >> > >> Thanks... > >> > >> ___ > >> 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] HP-3586B receiver...
I prefer the 3586-B version. I think it's more user friendly - once you get the hang of it, it does more. You can get off-the -shelf adaptors for the weird telco connectors to BNC for about $20, but it's simpler to just change out the connectors to BNC. The input module is a plug-in box. Remove six front panel screws, swing front panel out of the way, unplug the input module, replace connector, plug in the input module, look for screws you just had, replace just-lost screws, try again, and Voilla, normal connectors. The detection is only upper or lower sideband. Mine is GPS referenced and I use it for AM, PSK-31, RTTY, as well for FMT's. I live within 4 miles to two 50 KW AM stations and Have never had a problem when using my 210' Inverted-V. The selectable bandwidths with common options are: 3.1 kHz, 400 Hz, and 20 Hz. Marv Collins, W6OQI came over to our home about 3 years ago to look at the one I had at the time (I now have two of the B's). He said he doesn't know how he'd ever use one. Marv now has two of the B's. Burt, K6OQK At 12:32 PM 7/24/2010, time-nuts-requ...@febo.com wrote Subject: Re: [time-nuts] A Highly-Accurate and Stable SDR-IQ Using GPS-DO and DFS To: "paul swed" Cc: Discussion of precise time and frequency measurement Message-ID: <58923.12.6.201.2.1279990884.squir...@popaccts.quikus.com> Content-Type: text/plain;charset=iso-8859-1 Oops. Yes, typo. Sorry. I don't know about the A version but the and C are essentially identical except the B used wierd Telco connectors. An new adapter might cost as much as you'd pay for the receiver. Their shortfall is the demodulation options are limited, but they do a wonderful job of measuring carrier frequency. Best, -John Burt I. Weiner Associates Broadcast Technical Services Glendale, California U.S.A. b...@att.net www.biwa.cc K6OQK ___ 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] Symmetricom X72
Hello Bob, What would you recommend? I already have three FE-5680A Rb standards (which I'm quickly learning likely aren't worth the powder to blow them to (*insert your own word here*). Okay, that was probably my first mistake (thoughts?). My frequency counter is one I built from a kit from aade.com that has the TCXO option (although I had to tweak it myself so I have NO idea how close it is to any accuracy or precision). I have access to some really nice HP counters at work so that's my next step is to try one of those. My DFD4 measured the output of one of my 5680A's to 10.000.007 MHz after about a 10 minute warm-up. I don't know which one is off. Reading the specs on the 5680A's before I bought them looked like they were pretty decent. I'm learning... So, what "reasonably priced" Rb standard would you recommend? Should my next step in this process be a Trimble Thunderbolt? Am I starting over? Thanks... - Original Message - From: "Bob Camp" To: "Discussion of precise time and frequency measurement" Sent: Saturday, July 24, 2010 9:31 AM Subject: Re: [time-nuts] Symmetricom X72 Hi At least looking at the spec sheet it's not really very impressive. Bob On Jul 23, 2010, at 11:06 PM, Heathkid wrote: Hello. Does anyone have any experience with the Symmetricom X72? Thanks... ___ 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] Symmetricom X72
I installed one in a friends DEMI 10G transverter. It had microphonics and I am still trying to remove them. Stan, W1LE On 7/23/2010 11:06 PM, Heathkid wrote: Hello. Does anyone have any experience with the Symmetricom X72? Thanks... ___ 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] Basic question regarding comparing two frequencies
Thanks. I'll try that, with the x10 trace magnifier turned on my scope can resolve down to 2ns per division so that should work. - Original Message From: Bob Camp To: Discussion of precise time and frequency measurement Sent: Sat, July 24, 2010 10:51:21 AM Subject: Re: [time-nuts] Basic question regarding comparing two frequencies Hi If you have a fast enough scope you can also use the: Moved X ns in 10 seconds => X/10 ppb of frequency error. Bob On Jul 24, 2010, at 1:28 PM, Mark Spencer wrote: > Hello: > > Just for grins I decided to compare the frquency from my GPSDO to the time > base > > in my 5328A counter. > > > I connected the 10 mhz time base from the counter to channel A of my 100 Mhz > scope, fed the 10 mhz signal from my GPSDO into Channel B and with a T > adaptor > also fed this signal into the input of the counter. I scope to trigger > from > Channel B. > > > The drift betwen the two signals on the scope seems to match the error in the > displayed frquency on the counter. (ie. if the counter shows .9998 it >takes > > approx 5 seconds for the the wave form on channel A to slip a full cycle > realitve to channel B.) > > > Is this a reasonable approach or is there a better way to compare two > frequencies using a scope ? > > Best regards > Mark Spencer > > > > ___ > 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] Basic question regarding comparing two frequencies
Hi If you have a fast enough scope you can also use the: Moved X ns in 10 seconds => X/10 ppb of frequency error. Bob On Jul 24, 2010, at 1:28 PM, Mark Spencer wrote: > Hello: > > Just for grins I decided to compare the frquency from my GPSDO to the time > base > in my 5328A counter. > > > I connected the 10 mhz time base from the counter to channel A of my 100 Mhz > scope, fed the 10 mhz signal from my GPSDO into Channel B and with a T > adaptor > also fed this signal into the input of the counter.I scope to trigger > from > Channel B. > > > The drift betwen the two signals on the scope seems to match the error in the > displayed frquency on the counter. (ie. if the counter shows .9998 it > takes > approx 5 seconds for the the wave form on channel A to slip a full cycle > realitve to channel B.) > > > Is this a reasonable approach or is there a better way to compare two > frequencies using a scope ? > > Best regards > Mark Spencer > > > > ___ > 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] Basic question regarding comparing two frequencies
Hello: Just for grins I decided to compare the frquency from my GPSDO to the time base in my 5328A counter. I connected the 10 mhz time base from the counter to channel A of my 100 Mhz scope, fed the 10 mhz signal from my GPSDO into Channel B and with a T adaptor also fed this signal into the input of the counter. I scope to trigger from Channel B. The drift betwen the two signals on the scope seems to match the error in the displayed frquency on the counter. (ie. if the counter shows .9998 it takes approx 5 seconds for the the wave form on channel A to slip a full cycle realitve to channel B.) Is this a reasonable approach or is there a better way to compare two frequencies using a scope ? Best regards Mark Spencer ___ 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] A Highly-Accurate and Stable SDR-IQ Using GPS-DO and DFS
Oops. Yes, typo. Sorry. I don't know about the A version but the and C are essentially identical except the B used wierd Telco connectors. An new adapter might cost as much as you'd pay for the receiver. Their shortfall is the demodulation options are limited, but they do a wonderful job of measuring carrier frequency. Best, -John === > Indeed the do. I believe its actually a HP3586b a selective level > voltmeter. > One heck of a reciever measures signals to 100th of a db. As a heads up > they > have a very good xtal oven in them. I have 5 of these units. Just can not > resist them. > Often you find these quite cheap. Last one was $20 because it did not > work. > Well the oven had been taken. Ext ref did just fine. Mine are locked to a > Rb > standard. > Another big caution these have a nicad in them with a resistor for > charging. > They leak. > You need to pull the board and look at it and remove it before powering > up. > If the leakage has hit the traces, normal. It will raise holy heck and > damage the regulators. > Clean all the gook and repair any traces and you should be fine. > > On Fri, Jul 23, 2010 at 11:05 PM, J. Forster wrote: > >> If you want an HF radio that reads to a Hz, ready made, get a used HP >> (Agilent) 3486 Selective Level Meter. It covers essentially DC to either >> 20 or 30 MHz. It has a good internal ovenized oscillator, and can be >> locked to an external standard. >> >> A virtually unique feature is that it will lock onto a carrier and read >> that carrier frequency to a Hz or better. >> >> They are often abailable for a few hundred. The 3486A & B are similar. >> >> FWIW, >> >> -John >> >> = >> >> >> >> >> >> > I have been involved with many kinds of radio receivers for over fifty >> > years -- amateur, military, and commercial. This modified SDR-IQ is a >> > dream come true. When I was a young ham, I dreamed of the day when I >> might >> > have a receiver that would read out to one kilocycle (before we used >> the >> > term Hertz). Now I have assembled one that reads out to one Hertz and >> is >> > accurate to a few millihertz -- and thanks to GPS -- it will maintain >> this >> > accuracy as long as the GPS satellites keep working. >> > >> > I well remember the early radios that I used. I had to be very careful >> to >> > not bump the table where the radio was or it would jump completely off >> > frequency. Whatever frequency it indicated was only approximate. It >> made >> > me nervous to operate near a band edge. >> > >> > Dave Powis, G4HUP designed and built a 66.6 MHz DFS for me. I >> really >> > appreciate his help on this project, especially since several hams >> told >> me >> > it couldn't or shouldn't be done. Some said that the frequency >> read-out >> on >> > the SDR-IQ would not be accurate because the time-base in the >> computer's >> > sound card would be a variable factor, but this is not true. The >> frequency >> > accuracy and stability of this radio ONLY depends on the 10 MHz >> oscillator >> > in the Trimble Thunderbolt and that oscillator is locked to the GPS >> > constellation. >> > >> > Dave and I worked together on this project for about one year. The DFS >> box >> > travelled across the Atlantic Ocean five times before we finished. >> > >> > Dave has written an article "Precise Frequency Locking for the RFSpace >> SDR >> > radios" and I have a web page showing how I connected all of this >> > equipment together. Here are the links: >> > >> > http://www.braddye.com/g4hup_dfs.html >> > http://www.braddye.com/gps_do.html >> > >> > 73s >> > >> > Brad Dye, K9IQY >> > ex KN9IQY, KN4BK, KM5NK, WB4JCF, ZP5TQ, WA4VXU, WA9RVL, HH2FJ /TI2, >> /9Y4, >> > /6Y5, /KP4 >> > 53 years as a FCC licensed amateur radio operator >> > 37 years as a FCC licensed first class commercial radio operator >> > >> > >> > ___ >> > 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] Reference source 1E10^8 only ...Ideas
I use the 10 mhz signal from a simple GPSDO for this application. I suspect that doppler shift would prevent you from consistenly getting the accuracy you are looking for from the carrier of WWVH at your location. Regards Mark Spencer - Original Message From: Don Collie jnr To: time-nuts@febo.com Sent: Sat, July 24, 2010 5:33:08 AM Subject: [time-nuts] Reference source 1E10^8 only ...Ideas I need a frequency reference for my frequency counters, it needs to be accurate to at least +or- 1 part in 10,000,000. !0MHz would be OK, but also 5, or 1. Due to technical "improvements", the 4.43361875 MHz colour subcarrier which is available on the analogue TV system here in New Zealand, is no longer referenced to a Rubidium standard, and can be about +,- 1Hz in error. I have a communications receiver, and have been thinking of using this with Lyssajous figures on an oscilloscope, with the receiver tuned to WWVH in Hawaii, but a GPS might be a possability, if there is satellite coverage here in Invercargill, southern NZ. Bearing in mind I don`t need extreme accuracy, what is my best option, please?.Don. ___ 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] A Highly-Accurate and Stable SDR-IQ Using GPS-DO and DFS
Indeed the do. I believe its actually a HP3586b a selective level voltmeter. One heck of a reciever measures signals to 100th of a db. As a heads up they have a very good xtal oven in them. I have 5 of these units. Just can not resist them. Often you find these quite cheap. Last one was $20 because it did not work. Well the oven had been taken. Ext ref did just fine. Mine are locked to a Rb standard. Another big caution these have a nicad in them with a resistor for charging. They leak. You need to pull the board and look at it and remove it before powering up. If the leakage has hit the traces, normal. It will raise holy heck and damage the regulators. Clean all the gook and repair any traces and you should be fine. On Fri, Jul 23, 2010 at 11:05 PM, J. Forster wrote: > If you want an HF radio that reads to a Hz, ready made, get a used HP > (Agilent) 3486 Selective Level Meter. It covers essentially DC to either > 20 or 30 MHz. It has a good internal ovenized oscillator, and can be > locked to an external standard. > > A virtually unique feature is that it will lock onto a carrier and read > that carrier frequency to a Hz or better. > > They are often abailable for a few hundred. The 3486A & B are similar. > > FWIW, > > -John > > = > > > > > > > I have been involved with many kinds of radio receivers for over fifty > > years -- amateur, military, and commercial. This modified SDR-IQ is a > > dream come true. When I was a young ham, I dreamed of the day when I > might > > have a receiver that would read out to one kilocycle (before we used the > > term Hertz). Now I have assembled one that reads out to one Hertz and is > > accurate to a few millihertz -- and thanks to GPS -- it will maintain > this > > accuracy as long as the GPS satellites keep working. > > > > I well remember the early radios that I used. I had to be very careful to > > not bump the table where the radio was or it would jump completely off > > frequency. Whatever frequency it indicated was only approximate. It made > > me nervous to operate near a band edge. > > > > Dave Powis, G4HUP designed and built a 66.6 MHz DFS for me. I really > > appreciate his help on this project, especially since several hams told > me > > it couldn't or shouldn't be done. Some said that the frequency read-out > on > > the SDR-IQ would not be accurate because the time-base in the computer's > > sound card would be a variable factor, but this is not true. The > frequency > > accuracy and stability of this radio ONLY depends on the 10 MHz > oscillator > > in the Trimble Thunderbolt and that oscillator is locked to the GPS > > constellation. > > > > Dave and I worked together on this project for about one year. The DFS > box > > travelled across the Atlantic Ocean five times before we finished. > > > > Dave has written an article "Precise Frequency Locking for the RFSpace > SDR > > radios" and I have a web page showing how I connected all of this > > equipment together. Here are the links: > > > > http://www.braddye.com/g4hup_dfs.html > > http://www.braddye.com/gps_do.html > > > > 73s > > > > Brad Dye, K9IQY > > ex KN9IQY, KN4BK, KM5NK, WB4JCF, ZP5TQ, WA4VXU, WA9RVL, HH2FJ /TI2, /9Y4, > > /6Y5, /KP4 > > 53 years as a FCC licensed amateur radio operator > > 37 years as a FCC licensed first class commercial radio operator > > > > > > ___ > > 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] Reference source 1E10^8 only ...Ideas
Hi A lot depends on just how much trouble you want to go to. The TBolt is indeed a reasonable solution, it's overkill, but it will do everything you want to do. A free running Efratom LPRO 10 MHz rubidium also would do everything you need to do for a bit less money and a bit less hassle. A third alternative would be to simply use a decent modern 10 MHz OCXO. There are a number of double oven 10 MHz units that show up on the e-place regularly for a bit less money than either the LPRO or the TBolt. The OCXO should hold the level of accuracy you need for several years between calibrations. The disadvantage compared to the TBolt is that you would need to set up a calibration system. The TBolt with power (+/-12 and +5), antenna, shipping, and the various cables should come in for $150 to $250 (US). The LPro with power (+20) and shipping should be under $100 The OCXO with bench power (I assume +12 is there already) should be under $50. Possibly less if you go dumpster diving at Rakon... Lots of choices. Bob On Jul 24, 2010, at 8:33 AM, Don Collie jnr wrote: > I need a frequency reference for my frequency counters, it needs to be > accurate to at least +or- 1 part in 10,000,000. > !0MHz would be OK, but also 5, or 1. Due to technical "improvements", the > 4.43361875 MHz colour subcarrier which is available on the analogue TV system > here in New Zealand, is no longer referenced to a Rubidium standard, and can > be about +,- 1Hz in error. I have a communications receiver, and have been > thinking of using this with Lyssajous > figures on an oscilloscope, with the receiver tuned to WWVH in Hawaii, but a > GPS might be a possability, if there is satellite coverage here in > Invercargill, southern NZ. Bearing in mind I don`t need extreme accuracy, > what is my best option, > please?.Don. > ___ > 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] Reference source 1E10^8 only ...Ideas
On 07/24/2010 02:33 PM, Don Collie jnr wrote: I need a frequency reference for my frequency counters, it needs to be accurate to at least +or- 1 part in 10,000,000. !0MHz would be OK, but also 5, or 1. Due to technical "improvements", the 4.43361875 MHz colour subcarrier which is available on the analogue TV system here in New Zealand, is no longer referenced to a Rubidium standard, and can be about +,- 1Hz in error. I have a communications receiver, and have been thinking of using this with Lyssajous figures on an oscilloscope, with the receiver tuned to WWVH in Hawaii, but a GPS might be a possability, if there is satellite coverage here in Invercargill, southern NZ. Bearing in mind I don`t need extreme accuracy, what is my best option, please?.Don. For that level of quality, consider getting a cheap rubidium like the LPRO of Ebay. The prices is fairly humane. Build it into a box with a power-supply and a heatsink. Adding a fan helps to keep cooling sufficient at high temperature. If you want to be fancy, you can even put a servo-loop on the fan. Rubidiums have temperature stabilisations which wants a fairly high temperature (70 degrees and 130 degrees) but needs cooling, the higher cooling-plate temperature you allow yourself, the better the cooling must be, but the less heat is actually cooled off and thus consumed on the powerlines. Ah well. Optionally adding a PPS output with a SYNC input would ease comparision with a simple GPS. Adding a multi-turn high quality potentiometer for manual EFC tuning to keep it inline with GPS would suffice for your needs. You might want some form of voltage reference to give the reference voltage to the potentiometer. Maybe a REF10 would suffice. The +/- 1 Hz on the PAL subcarrier is within the standard, so they are allowed to relax it to that... but it is a pitty they don't lock it up to propper reference. The only guys doing PAL transmissions here in Sweden is the radio-amateurs. I would not bet that their carrier and rig is locked to a atomic reference at all times. 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] GR 1115B
Hi My impression is that a lot of these guys put up a list of "everything and anything on the planet" so the search engines find them. Still no luck on a free download manual. I may actually have to buy the GR cdrom. Bob On Jul 24, 2010, at 4:53 AM, K. Szeker wrote: > Sorry Bob, > but the home addresse is working: > http://www.imltest.com/ > I found a very long listing on "inventory" yesterday, it was me only not > full clear if its a real listing of "manual s to have" or they does serve > repairing for the mentioned types... > K. > > 2010/7/24 K. Szeker > >> Hi Bob, >> >> Raeser service repairs it_hopefuly have some documentations too? >> http://www.raeservices.com/product-detail.asp?search=67241 >> Seems; they have a manual too? http://www.imltest.com/inventory. >> > >> Karesz >> >> 2010/7/24 Bob Camp >> >> Hi >>> >>> A GR 1115B seems to be headed this way. I have no idea what condition it's >>> in. About all I have been able to find is the GR news article on the unit >>> from 1961(?). Does anybody have a schematic or manual? >>> >>> Thanks! >>> >>> Bob >>> ___ >>> 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] Symmetricom X72
Hi At least looking at the spec sheet it's not really very impressive. Bob On Jul 23, 2010, at 11:06 PM, Heathkid wrote: > Hello. Does anyone have any experience with the Symmetricom X72? > > Thanks... > > ___ > 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] Reference source 1E10^8 only ...Ideas
On 07/24/2010 02:33 PM, Don Collie jnr wrote: I need a frequency reference for my frequency counters, it needs to be accurate to at least +or- 1 part in 10,000,000. For a home-cooked gpsdo in the really low end I have this bit to offer: http://n1.taur.dk/simplexdo/ It was built to be an always calibrated and ready, pocketable, instant-on source. Not to compete with something like a second hand Tbolt. /Kasper Pedersen ___ 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] Reference source 1E10^8 only ...Ideas
Don, Go to fluke.l (that's a lower case l at the end) seller on eBay, and buy a Thunderbolt GPS controlled oscillator. You should have fully adequate satellite coverage at 45 or 50 degrees South PS Once I get the parts through I'll have a divider board available. Cheers Dave -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Don Collie jnr Sent: 24 July 2010 13:33 To: time-nuts@febo.com Subject: [time-nuts] Reference source 1E10^8 only ...Ideas I need a frequency reference for my frequency counters, it needs to be accurate to at least +or- 1 part in 10,000,000. !0MHz would be OK, but also 5, or 1. Due to technical "improvements", the 4.43361875 MHz colour subcarrier which is available on the analogue TV system here in New Zealand, is no longer referenced to a Rubidium standard, and can be about +,- 1Hz in error. I have a communications receiver, and have been thinking of using this with Lyssajous figures on an oscilloscope, with the receiver tuned to WWVH in Hawaii, but a GPS might be a possability, if there is satellite coverage here in Invercargill, southern NZ. Bearing in mind I don`t need extreme accuracy, what is my best option, please?.Don. ___ 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] Reference source 1E10^8 only ...Ideas
Don, A GPSDO would suit you fine, perhaps a Thunderbolt as that seems to be well know and respected here, and is a relatively inexpensive way to get a GPS disciplined oscillator. There is plenty of coverage of sats in NZ, I'm in Christchurch and daily track up to 12 on a Z3805A at any one time. You could always buy your own used Rb oscillator, like an LPRO, as these are easily available on fleeBay from sellers like Bob Mokia (fluke.l) but you would need something to calibrate it with in the first place (possibly someone else's standard). These are used Rb units and have had their planned life already but the telecom's providers that have used them have generally bargained on a reasonable safety margin so you are likely to get a few more years out of them depending on the duty cycle you are using them. Steve On 25/07/2010, Don Collie jnr wrote: > I need a frequency reference for my frequency counters, it needs to be > accurate to at least +or- 1 part in 10,000,000. > !0MHz would be OK, but also 5, or 1. Due to technical "improvements", the > 4.43361875 MHz colour subcarrier which is available on the analogue TV > system here in New Zealand, is no longer referenced to a Rubidium standard, > and can be about +,- 1Hz in error. I have a communications receiver, and > have been thinking of using this with Lyssajous > figures on an oscilloscope, with the receiver tuned to WWVH in Hawaii, but a > GPS might be a possability, if there is satellite coverage here in > Invercargill, southern NZ. Bearing in mind I don`t need extreme accuracy, > what is my best option, > please?.Don. > ___ > 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. > -- Steve Rooke - ZL3TUV & G8KVD The only reason for time is so that everything doesn't happen at once. - Einstein ___ 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] Reference source 1E10^8 only ...Ideas
I need a frequency reference for my frequency counters, it needs to be accurate to at least +or- 1 part in 10,000,000. !0MHz would be OK, but also 5, or 1. Due to technical "improvements", the 4.43361875 MHz colour subcarrier which is available on the analogue TV system here in New Zealand, is no longer referenced to a Rubidium standard, and can be about +,- 1Hz in error. I have a communications receiver, and have been thinking of using this with Lyssajous figures on an oscilloscope, with the receiver tuned to WWVH in Hawaii, but a GPS might be a possability, if there is satellite coverage here in Invercargill, southern NZ. Bearing in mind I don`t need extreme accuracy, what is my best option, please?.Don. ___ 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] GR 1115B
Sorry Bob, but the home addresse is working: http://www.imltest.com/ I found a very long listing on "inventory" yesterday, it was me only not full clear if its a real listing of "manual s to have" or they does serve repairing for the mentioned types... K. 2010/7/24 K. Szeker > Hi Bob, > > Raeser service repairs it_hopefuly have some documentations too? > http://www.raeservices.com/product-detail.asp?search=67241 > Seems; they have a manual too? http://www.imltest.com/inventory. > > Karesz > > 2010/7/24 Bob Camp > > Hi >> >> A GR 1115B seems to be headed this way. I have no idea what condition it's >> in. About all I have been able to find is the GR news article on the unit >> from 1961(?). Does anybody have a schematic or manual? >> >> Thanks! >> >> Bob >> ___ >> 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.
