[time-nuts] Tek 2252 scope as an TI counter (pt 2)
A few months ago I mentioned that I was able to use my Tek 2252 scope as a Time interval counter. Yesterday I wrote an EZ GPIB script (thanks to the author of this useful software !) to collect data via the GPIB port and after three runs alternately feeding 5 and 10 Mhz signals in to the "start" and "stop" ports via a T connector with un equal length cables the performance appears to be quite good with the standard deviation of the time interval readings being slightly less than 10 ps for each run. This is several times better than my HP 5370B. While this unit is not as versatile as real counter and has a number of limitations, (ie. the readings are taken at a fixed interval of approx 0.8 seconds) the raw performance appears to be quite good. If anyone would like more details feel free to contact me off list. 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] Sidereal timekeeping
> As an alternative you could build an external circuit (a few uA at 3V > supply) and generate a signal to inject into the existing Xtal osc with the > Xtal removed. In a typical battery operated clock, what fraction of the power goes to the oscillator and counter and how much goes to the motor? -- 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] Sidereal timekeeping
Hi Antonio, the 32kHz Xtals are 2mm long tuning forks (that is what I believe although I have not opened one). You would have very little chance of modifying it and still have enough Q left for it to oscillate. As an alternative you could build an external circuit (a few uA at 3V supply) and generate a signal to inject into the existing Xtal osc with the Xtal removed. The type of circuit that I would build would be a cmos binary divider connected to a quad gate. The 4 gate inputs connect to selected binary stages of the divider. When the gate decodes the selected number, an extra pulse is added to the count chain. The output is thus shifted to a higher frequency. If you are interested I can try to design the circuit for you, I have intend to build a Siderial clock dial for my TBolt. cheers, Neville Michie On 17/05/2011, at 7:58 AM, iov...@inwind.it wrote: Neville, at present I have not enough skill with micros to solve the problem. I think I will try modifying a crystal. This would not be that difficult using a lapping sheet or the like. And opening the can would be quite easy using hot air. This is the fastest way for me, and the device will continue to be powered by a simple AA cell, which is a non negligible advantage in my application. All the best, Antonio I8IOV Antonio, it is quite easy to make an external circuit that uses a 32kHz xtal and divides it down to siderial seconds. It is also easy to drive most analog quartz clock movements from an external circuit. Just what signal do you need? What frequency? and what does it drive? (an alternate polarity quartz clock motor?) It can also be done with a micro if you have the skills. cheers, Neville Michie ___ 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] DATUM 9390 Question...
Eugene, I have two of the DATUM 9390-5054 instruments with the original antennas and 100 foot feedline that I have above tree line and well in the clear. I have worked with many of this model receiver and my experience is that it is not uncommon for them to begin to gather satellites, having all four SVs looking happy and ten drop back down to none, or only one or two satellites. He may do this once or even twice then settle down and do his thing. Be patient. There is a Master Reset performed by turning the unit off, lowering one of the DIP switches, turning the unit on waiting about 30 seconds and then turning the unit off and then returning the DIP switch back up. The bad part is that I don't remember which DIP switch! I'll see if I can find that in my notes. Really, the only time this is handy, not mandatory, is when the unit has been moved to a different location since it was last fully operational. This reset will clear out the old Almanac and give it a fresh start. Even if you don't do this it will work just fine but will take a longer time to figure out where he is and start to gather satellites. One thing you will want to check is that the DAC number is around 27,000. This can be set by removing the protective cover screw for the oscillator in the back of the receiver and using a long insulated screw-driver to set the set the oscillator (Well, I suppose it depends on which oscillator you unit has in it.). Looking at it from the back, turning the screw counter-clockwise lowers the DAC and CW (obviously) raises the DAC. What I have found as a happy way to set a receiver that has been sitting for a long time is to turn the instrument on without the antenna connected, let it warm up for a while and ten setting the oscillator as described above for an output frequency of 10 MHz - as close as you can get it with out going crazy. Anywhere within 1 Hz is plenty close enough to make it happy for a start. Mine usually settle down to 1 to 10 E-12 after about 24 hours. Periodically check the DAC - maybe once a month. It will be happy if it's between 20,000 to 45,000. Once in a while I tweak mine back to around 27,000 using the procedure I described above. I never tweak both, just one at a time, let it settle in for a day or two and then I'll tweak the other one. A sign that the DAC may be getting close to its limit is that the instrument will likely drop out of lock every once in a while or more often depending on how close to the limit he really is. I hope this is of some help. Burt, K6OQK At 08:02 PM 5/15/2011, time-nuts-requ...@febo.com wrote > On Sun, May 15, 2011 at 6:30 PM, W2HX wrote: > > Hi there. Recently acquired my first GPSDO. It is a datum 9390 (thank you, > Norm!). One aspect of its behavior seems strange to me. Within a matter > of > a few minutes, it seems that satellites are appearing and disappearing. > Are > the satellites moving that quickly? I might go from 1SV to 3SV or 4SV and > then a minute later go to 1SV or none. The antenna isn't moving and the > trees aren't moving too much today. I have not done anything with regard > to > setting minimum elevation or any other parameters. I did go through the > COLD RESTART procedure to clear out everything and let it start from > scratch. > > > > Do other GPSDO users experience something like this? > > 73 Eugene W2HX 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] Sidereal timekeeping
Jim Lux wrote: On 5/16/11 2:58 PM, iov...@inwind.it wrote: Neville, at present I have not enough skill with micros to solve the problem. I think I will try modifying a crystal. This would not be that difficult using a lapping sheet or the like. And opening the can would be quite easy using hot air. or a fine jeweler's saw or tubing cutter. As you pointed out, the crystals are cheap, so you can afford to ruin a few while figuring out how to do it. (and then, remember us all, when you're a multi-billionaire having cornered the market on sidereal rate crystals) Since the 32 kHz crystal is likely to be a tuning fork form, one merely needs to shorten the tines to increase the frequency. It may be feasible to do this without removing any of the electrode metallization. Bruce ___ 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] Sidereal timekeeping
On 5/16/11 2:58 PM, iov...@inwind.it wrote: Neville, at present I have not enough skill with micros to solve the problem. I think I will try modifying a crystal. This would not be that difficult using a lapping sheet or the like. And opening the can would be quite easy using hot air. or a fine jeweler's saw or tubing cutter. As you pointed out, the crystals are cheap, so you can afford to ruin a few while figuring out how to do it. (and then, remember us all, when you're a multi-billionaire having cornered the market on sidereal rate crystals) ___ 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] Bob Camp - bounced email
Apologies to the rest of the list ... @Bob Camp, Thank you for your e-mail! I tried to send you a reply twice, but both attempts bounced on what looks like spamcop handling mail for your domain. First attempt was a direct reply-to with a legit reply header. The second attempt was a new e-mail, but not surprisingly both bounced the exact same way. This is from a yahoo account, so maybe it doesn't like the particular yahoo mailserver. Any other way? sorry for the inconvenience... Fred ___ 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] Sidereal timekeeping
Neville, at present I have not enough skill with micros to solve the problem. I think I will try modifying a crystal. This would not be that difficult using a lapping sheet or the like. And opening the can would be quite easy using hot air. This is the fastest way for me, and the device will continue to be powered by a simple AA cell, which is a non negligible advantage in my application. All the best, Antonio I8IOV >Antonio, >it is quite easy to make an external circuit that uses a 32kHz xtal >and divides >it down to siderial seconds. It is also easy to drive most analog >quartz clock movements from >an external circuit. >Just what signal do you need? What frequency? and what does it drive? >(an alternate polarity >quartz clock motor?) >It can also be done with a micro if you have the skills. >cheers, Neville Michie ___ 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 on GPS satellites
Lots of good answers I do not select a mask Most of my rcvrs will guess are 10 degrees mask. But that just happens to be were they come in at. My antenna is at 45 foot on a 95 foot tower on the south side. There are 70 foot trees around me. I use 1/2" catv hard line very low loss and free. Hit a 4 way 2.5 Ghz splitter feeding 4 rcvrs. Designing a 8 way splitter with amplifier over the next few weeks using a 31 to 1 2.1 GHz combiner works well at 1.5 Ghz. Cut out 3 1 X 8 sections for now. Total gain after splits will + 6db. port to port isolation will be about 20 db. Will see how it all plays out. Regards Paul WB8TSL On Mon, May 16, 2011 at 11:13 AM, Chris Albertson wrote: > Another way to go is to move the GPS receiver so that it is close to > the antenna, then use a long RS232 serial cable. Or if the distance > is more than 100 feet uses a balanced type of serieal. You can use > Cat-5 cable for this and there ar enough pairs in cat-5 so that you > can send DC power on the same cable. This is cheap than a log coax > cable and there is even less cable loss. > > On Sun, May 15, 2011 at 8:39 PM, WB6BNQ wrote: > > Paul, > > > > If you had read more carefully what I wrote you would see that I said > better coax > > "WHEN HE PUTS IT OUTSIDE." > > -- > = > Chris Albertson > Redondo Beach, California > > ___ > 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] Results parts selection + commercial assembly poll?
Since the last few post on that "alternate list" were by me, and were never answered, my working assumption was much the same thing. Apparently not enough interest. Oh well, slowly plow forward on my own then. Which is a bit of a pity, since I am sure that with a few people (3 or so) this whole DIY counter business is going to be better and done quicker. But no interest is no interest. regards, Fred PS: and yes that was a hint. Get to it already, you collective fence sitters. :P From: Bob Bownes To: Discussion of precise time and frequency measurement Cc: Tijd Dingen Sent: Monday, May 16, 2011 5:56 PM Subject: Re: [time-nuts] Results parts selection + commercial assembly poll? I'll add that for some reason the discussion never morphed over to an alternate list created just to discuss a counter project without taking up bandwidth here. Not sure that there was enough interest. Other Bob On Mon, May 16, 2011 at 11:53 AM, Bob Camp wrote: > Hi > > The polls ran for less than a day before they drew considerable fire for > using too much bandwidth. Since we still had several steps to go (what to > design, what to design it with, and who to design what), it was dropped. > Doing a group general purpose FPGA based timing board isn't going to happen > within the perceived bandwidth limits here. > > Bob > > -Original Message- > From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On > Behalf Of Tijd Dingen > Sent: Saturday, May 14, 2011 5:04 PM > To: time-nuts@febo.com > Subject: [time-nuts] Results parts selection + commercial assembly poll? > > Incidentally, did something ever come of these two polls? I was trying find > the conclusion / results, but could not find it on the list. Entirely > possible that I am blind for which I apologize in advance. Anyone know what > came of it? > > regards, > Fred > ___ > 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] Results parts selection + commercial assembly poll?
Hi I think the reference is to whole "take it off line" part of the discussion. The reasons for not doing so were explained at the time, so really don't require repeating again. Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Scott Newell Sent: Monday, May 16, 2011 3:00 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Results parts selection + commercial assembly poll? At 01:38 PM 5/16/2011, Bill Hawkins wrote: >Part of the problem is that this list discourages off-list >discussion by not providing the individual's email address. What? I'm looking at the from: header and see "Bill Hawkins" . -- newell N5TNL ___ 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] Results parts selection + commercial assembly poll?
At 01:38 PM 5/16/2011, Bill Hawkins wrote: Part of the problem is that this list discourages off-list discussion by not providing the individual's email address. What? I'm looking at the from: header and see "Bill Hawkins" . -- newell N5TNL ___ 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] Results parts selection + commercial assembly poll?
As I recall, the thread looked like marketing research for a profitable product, not design research for the benefit of list members. Part of the problem is that this list discourages off-list discussion by not providing the individual's email address. If the original poll request gave the sender's address and made it clear that their mailer's Reply key was the wrong thing to use, we might not be having this discussion. You can reply to me at b...@iaxs.net. I'm already on all of the spam lists, and Red Condor filters all of the spam. Bill Hawkins -Original Message- From: Bob Bownes Sent: Monday, May 16, 2011 12:15 PM I was more wondering why the discussion never moved, not why the project discussion died here. But this is probably enough bandwidth wasted again. :) ___ 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] Results parts selection + commercial assembly poll?
I was more wondering why the discussion never moved, not why the project discussion died here. But this is probably enough bandwidth wasted again. :) On Mon, May 16, 2011 at 12:46 PM, Bob Camp wrote: > Hi > > The issue that killed it was at least one member objecting quite strenuously > to the bandwidth used. > > The counter project was the initial spark that started it all, but the > objective of the polls was more general. You can indeed build a piece of > hardware and then tell it what it is after it's built. The one you have > might be a general purpose counter, the one somebody else has might be > something totally different. > > With modern parts, design isn't to hard, the big constraint on it is > construction techniques. Most of the cheap / neat stuff you would use is > tough to put on a board. There's no use in starting a design effort and > ruling out all the likely solutions after it's started. > > Bob > > -Original Message- > From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On > Behalf Of Bob Bownes > Sent: Monday, May 16, 2011 11:56 AM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Results parts selection + commercial assembly poll? > > I'll add that for some reason the discussion never morphed over to an > alternate list created just to discuss a counter project without > taking up bandwidth here. Not sure that there was enough interest. > > Other Bob > > > On Mon, May 16, 2011 at 11:53 AM, Bob Camp wrote: >> Hi >> >> The polls ran for less than a day before they drew considerable fire for >> using too much bandwidth. Since we still had several steps to go (what to >> design, what to design it with, and who to design what), it was dropped. >> Doing a group general purpose FPGA based timing board isn't going to > happen >> within the perceived bandwidth limits here. >> >> Bob >> >> -Original Message- >> From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On >> Behalf Of Tijd Dingen >> Sent: Saturday, May 14, 2011 5:04 PM >> To: time-nuts@febo.com >> Subject: [time-nuts] Results parts selection + commercial assembly poll? >> >> Incidentally, did something ever come of these two polls? I was trying > find >> the conclusion / results, but could not find it on the list. Entirely >> possible that I am blind for which I apologize in advance. Anyone know > what >> came of it? >> >> regards, >> Fred >> ___ >> 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] Results parts selection + commercial assembly poll?
Hi The issue that killed it was at least one member objecting quite strenuously to the bandwidth used. The counter project was the initial spark that started it all, but the objective of the polls was more general. You can indeed build a piece of hardware and then tell it what it is after it's built. The one you have might be a general purpose counter, the one somebody else has might be something totally different. With modern parts, design isn't to hard, the big constraint on it is construction techniques. Most of the cheap / neat stuff you would use is tough to put on a board. There's no use in starting a design effort and ruling out all the likely solutions after it's started. Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Bob Bownes Sent: Monday, May 16, 2011 11:56 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Results parts selection + commercial assembly poll? I'll add that for some reason the discussion never morphed over to an alternate list created just to discuss a counter project without taking up bandwidth here. Not sure that there was enough interest. Other Bob On Mon, May 16, 2011 at 11:53 AM, Bob Camp wrote: > Hi > > The polls ran for less than a day before they drew considerable fire for > using too much bandwidth. Since we still had several steps to go (what to > design, what to design it with, and who to design what), it was dropped. > Doing a group general purpose FPGA based timing board isn't going to happen > within the perceived bandwidth limits here. > > Bob > > -Original Message- > From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On > Behalf Of Tijd Dingen > Sent: Saturday, May 14, 2011 5:04 PM > To: time-nuts@febo.com > Subject: [time-nuts] Results parts selection + commercial assembly poll? > > Incidentally, did something ever come of these two polls? I was trying find > the conclusion / results, but could not find it on the list. Entirely > possible that I am blind for which I apologize in advance. Anyone know what > came of it? > > regards, > Fred > ___ > 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] Results parts selection + commercial assembly poll?
I'll add that for some reason the discussion never morphed over to an alternate list created just to discuss a counter project without taking up bandwidth here. Not sure that there was enough interest. Other Bob On Mon, May 16, 2011 at 11:53 AM, Bob Camp wrote: > Hi > > The polls ran for less than a day before they drew considerable fire for > using too much bandwidth. Since we still had several steps to go (what to > design, what to design it with, and who to design what), it was dropped. > Doing a group general purpose FPGA based timing board isn't going to happen > within the perceived bandwidth limits here. > > Bob > > -Original Message- > From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On > Behalf Of Tijd Dingen > Sent: Saturday, May 14, 2011 5:04 PM > To: time-nuts@febo.com > Subject: [time-nuts] Results parts selection + commercial assembly poll? > > Incidentally, did something ever come of these two polls? I was trying find > the conclusion / results, but could not find it on the list. Entirely > possible that I am blind for which I apologize in advance. Anyone know what > came of it? > > regards, > Fred > ___ > 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] Results parts selection + commercial assembly poll?
Hi The polls ran for less than a day before they drew considerable fire for using too much bandwidth. Since we still had several steps to go (what to design, what to design it with, and who to design what), it was dropped. Doing a group general purpose FPGA based timing board isn't going to happen within the perceived bandwidth limits here. Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Tijd Dingen Sent: Saturday, May 14, 2011 5:04 PM To: time-nuts@febo.com Subject: [time-nuts] Results parts selection + commercial assembly poll? Incidentally, did something ever come of these two polls? I was trying find the conclusion / results, but could not find it on the list. Entirely possible that I am blind for which I apologize in advance. Anyone know what came of it? regards, Fred ___ 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 on GPS satellites
Another way to go is to move the GPS receiver so that it is close to the antenna, then use a long RS232 serial cable. Or if the distance is more than 100 feet uses a balanced type of serieal. You can use Cat-5 cable for this and there ar enough pairs in cat-5 so that you can send DC power on the same cable. This is cheap than a log coax cable and there is even less cable loss. On Sun, May 15, 2011 at 8:39 PM, WB6BNQ wrote: > Paul, > > If you had read more carefully what I wrote you would see that I said better > coax > "WHEN HE PUTS IT OUTSIDE." -- = Chris Albertson Redondo Beach, California ___ 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] Sidereal timekeeping
Nope - you're right - most don't go below 1MHz. Got a little loose with my K's and M's I guess. Kinda like - "what's 3dB among friends?" My apologies for the stray lead. Thanks for catching it Jim. Brent On Mon, May 16, 2011 at 10:21 AM, Jim Lux wrote: > On 5/16/11 6:30 AM, brent evers wrote: >> >> Can't you just use a programmable crystal? Digikey will do this for >> you prior to ship. Search on crystal, then under the field type, >> filter by "Programmed by Digikey". Four types pop up as in stock. >> Not sure if they would meet you footprint requirement, but its worth a >> shot. >> > > > Do those go down to 32kHz? We've used them at work in the 40-60 MHz range > (by the way, the noise properties leave something to be desired.. you don't > want to be using them as the reference oscillator for a microwave PLL), but > I don't know if they go low. > > They're also fairly high power (compared to running a clock off a single AA > battery) > > > ___ > 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] Sidereal timekeeping
On 5/16/11 6:30 AM, brent evers wrote: Can't you just use a programmable crystal? Digikey will do this for you prior to ship. Search on crystal, then under the field type, filter by "Programmed by Digikey". Four types pop up as in stock. Not sure if they would meet you footprint requirement, but its worth a shot. Do those go down to 32kHz? We've used them at work in the 40-60 MHz range (by the way, the noise properties leave something to be desired.. you don't want to be using them as the reference oscillator for a microwave PLL), but I don't know if they go low. They're also fairly high power (compared to running a clock off a single AA battery) ___ 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 on GPS satellites
Do you have a mask set on the signal level? I have two tbolts running that are completely surrounded by trees, and I was getting satellites popping in and out. I dropped the AMU to 0.0 and it is much more stable as to not dropping birds, although I have absolutley no idea what effect that might have had on the stability of the 10.0M reference. Also, a high elevation mask can do the same. Any reflection/comment as to the effect of my doing the above is appreciated. Brent On Mon, May 16, 2011 at 8:49 AM, paul swed wrote: > ok > Indeed now that its morning and different glasses I would have seen that. > There you go dangerous at 11pm > > On Sun, May 15, 2011 at 11:39 PM, WB6BNQ wrote: > >> Paul, >> >> If you had read more carefully what I wrote you would see that I said >> better coax >> "WHEN HE PUTS IT OUTSIDE." >> >> thank you, >> >> BillWB6BNQ >> >> >> paul swed wrote: >> >> > 12' of rg 58 should be fine and 5-3.7V should work >> > In the thread it says this is using a window. Boy some windows actually >> can >> > block the signal especially if there is a screen. >> > Some one else said you need a view to the south. Thats a fact from ma. at >> > least interesting to watch the sat tracks. I would not have believed they >> > travel the way they do. >> > Strongly believe you need to see clear sky. Signal to noise ratio. >> > Lastly its late forgive typos. >> > >> > On Sun, May 15, 2011 at 11:01 PM, WB6BNQ wrote: >> > >> > > Hi Eugene, >> > > >> > > I will presume from your call sign that you are North of the equator. >> Thus >> > > you >> > > would want to have the best visibility (i.e., clear) pointing to the >> South. >> > > The >> > > fact that you are at the window, on the inside, does limit the amount >> of >> > > sky you >> > > can see. Just getting it on the roof will make a reasonable >> difference. >> > > Getting >> > > above, or reasonably at the same height as, the trees should be the >> goal. >> > > >> > > I would use something better then RG-58 when you put it outside. Even >> RG-6 >> > > with >> > > quality connectors, the good type used by the cable TV companies, is >> better >> > > than >> > > RG-58 at the GPS frequency. >> > > >> > > As for increasing the voltage to the antenna, I would definitely be >> careful >> > > there. No doubt a regulator of some sort is used up at the antenna and >> > > raising >> > > the voltage would just make that regulator work harder. If the voltage >> is >> > > well >> > > lower than the specified 5 volts, I would investigate why that is. >> Could >> > > be your >> > > meter is off ? The only reason for raising the voltage a TAD would be >> if >> > > you had >> > > a very long run (like over 200 feet) to compensate for I*R losses if >> they >> > > are >> > > significant. However, such a long run would be counterproductive due >> to >> > > line >> > > loss at the RF frequency of the GPS. >> > > >> > > 73BillWB6BNQ >> > > >> > > W2HX wrote: >> > > >> > > > Length is about 12', type is RG-58, antenna is at my window pointing >> to a >> > > > some blue sky (no splitter). I think from the emails from the folks >> on >> > > the >> > > > list, before anything, I need to find a better location for the >> antenna. >> > > > Thanks for the reply >> > > > >> > > > 73 Eugene W2HX >> > > > >> > > > -Original Message- >> > > > From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] >> On >> > > > Behalf Of Scott Mace >> > > > Sent: Sunday, May 15, 2011 10:07 PM >> > > > To: time-nuts@febo.com >> > > > Subject: Re: [time-nuts] basic question on GPS satellites >> > > > >> > > > What type of coax are you using and how long is the run? >> > > > >> > > > I live in the woods and my antenna is partially blocked by >> > > > trees to the north and east and have never had problems. I have >> about >> > > > 130ft of LMR-400 between my antenna and splitter. >> > > > >> > > > Scott >> > > > >> > > > On 05/15/2011 05:30 PM, W2HX wrote: >> > > > > Hi there. Recently acquired my first GPSDO. It is a datum 9390 >> (thank >> > > you, >> > > > > Norm!). One aspect of its behavior seems strange to me. Within a >> > > matter >> > > > of >> > > > > a few minutes, it seems that satellites are appearing and >> disappearing. >> > > > Are >> > > > > the satellites moving that quickly? I might go from 1SV to 3SV or >> 4SV >> > > and >> > > > > then a minute later go to 1SV or none. The antenna isn't moving >> and >> > > the >> > > > > trees aren't moving too much today. I have not done anything with >> > > regard >> > > > to >> > > > > setting minimum elevation or any other parameters. I did go >> through >> > > the >> > > > > COLD RESTART procedure to clear out everything and let it start >> from >> > > > > scratch. >> > > > > >> > > > > >> > > > > >> > > > > Do other GPSDO users experience something like this? >> > > > > >> > > > > 73 Eugene W2HX >> > > > > >> > > > > >> > > > > >> > > > > _
Re: [time-nuts] Sidereal timekeeping
Can't you just use a programmable crystal? Digikey will do this for you prior to ship. Search on crystal, then under the field type, filter by "Programmed by Digikey". Four types pop up as in stock. Not sure if they would meet you footprint requirement, but its worth a shot. Brent On Mon, May 16, 2011 at 8:08 AM, Neville Michie wrote: > Antonio, > it is quite easy to make an external circuit that uses a 32kHz xtal and > divides > it down to siderial seconds. It is also easy to drive most analog quartz > clock movements from > an external circuit. > Just what signal do you need? What frequency? and what does it drive? (an > alternate polarity > quartz clock motor?) > It can also be done with a micro if you have the skills. > cheers, Neville Michie > > > On 16/05/2011, at 8:02 PM, iov...@inwind.it wrote: > >> The background of my request is an OT story. Just to mention briefly, I >> already >> have an ordinary (non-radio-controlled) clock machine which turns a >> miniature >> torsion balance in a sealed glass vessel. It runs on a single AA battery. >> No >> extreme accuracy needed. I wont to modify the rate to sidereal, and might >> have >> to replicate the setup too. I figure that the solution I should pursue is >> getting the "odd" crystals. >> Now it is clear to me that I have to explore two options, a) contacting a >> crystal manufacturer, b) modifying 32768 crystals. >> Thanks, >> Antonio >> >> hmur...@megapathdsl.net wrote: >>> does anybody out there have any ideas as where to find a 32859Hz crystal >> >> (1/ 2 that value would be better) to be used to replace 32768 crystals in ordinary clocks? I think that 32768 crystals cannot be dragged that much. I've already read the JimLux article somewhere on the web, but I would be pleased finding a simpler solution. Also, I already have computer programs that show sidereal time. >>> >>> I think it depends upon what you mean by "ordinary clocks". >>> >>> Most of the recent wall clocks I've seen are battery powered (single AA) >>> and >>> resynchronize nightly via WWVB. >>> >>> If you want sidereal time, you won't have anything to synchronize to. >>> What >>> sort of accuracy are you interested in? If you want reasonable accuracy, >> >> you >>> >>> will need an external signal. (You can provide power over the same >>> cable.) >>> >>> My straw man would be to send 32859Hz down coax or twisted pair and feed >>> it >>> into the xtal-in pin on the clock chip. I'm not sure how to set the >>> time. >>> You can cut the lead to the antenna to make sure it doesn't sync to WWVB. >>> >>> You can make 32859Hz from a PIC (or any micro you like) running off any >> >> handy >>> >>> frequency. Given that this is time-nuts, I'd suggest 10 MHz from a >>> GPSDO. >>> >>> It might be simpler to dump the 32KHz and WWVB chip and drive the motor >>> directly from a 1 PPS signal. Just use a sidereal second rather than a >>> normal second. >> >> >> >> >> ___ >> 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 on GPS satellites
ok Indeed now that its morning and different glasses I would have seen that. There you go dangerous at 11pm On Sun, May 15, 2011 at 11:39 PM, WB6BNQ wrote: > Paul, > > If you had read more carefully what I wrote you would see that I said > better coax > "WHEN HE PUTS IT OUTSIDE." > > thank you, > > BillWB6BNQ > > > paul swed wrote: > > > 12' of rg 58 should be fine and 5-3.7V should work > > In the thread it says this is using a window. Boy some windows actually > can > > block the signal especially if there is a screen. > > Some one else said you need a view to the south. Thats a fact from ma. at > > least interesting to watch the sat tracks. I would not have believed they > > travel the way they do. > > Strongly believe you need to see clear sky. Signal to noise ratio. > > Lastly its late forgive typos. > > > > On Sun, May 15, 2011 at 11:01 PM, WB6BNQ wrote: > > > > > Hi Eugene, > > > > > > I will presume from your call sign that you are North of the equator. > Thus > > > you > > > would want to have the best visibility (i.e., clear) pointing to the > South. > > > The > > > fact that you are at the window, on the inside, does limit the amount > of > > > sky you > > > can see. Just getting it on the roof will make a reasonable > difference. > > > Getting > > > above, or reasonably at the same height as, the trees should be the > goal. > > > > > > I would use something better then RG-58 when you put it outside. Even > RG-6 > > > with > > > quality connectors, the good type used by the cable TV companies, is > better > > > than > > > RG-58 at the GPS frequency. > > > > > > As for increasing the voltage to the antenna, I would definitely be > careful > > > there. No doubt a regulator of some sort is used up at the antenna and > > > raising > > > the voltage would just make that regulator work harder. If the voltage > is > > > well > > > lower than the specified 5 volts, I would investigate why that is. > Could > > > be your > > > meter is off ? The only reason for raising the voltage a TAD would be > if > > > you had > > > a very long run (like over 200 feet) to compensate for I*R losses if > they > > > are > > > significant. However, such a long run would be counterproductive due > to > > > line > > > loss at the RF frequency of the GPS. > > > > > > 73BillWB6BNQ > > > > > > W2HX wrote: > > > > > > > Length is about 12', type is RG-58, antenna is at my window pointing > to a > > > > some blue sky (no splitter). I think from the emails from the folks > on > > > the > > > > list, before anything, I need to find a better location for the > antenna. > > > > Thanks for the reply > > > > > > > > 73 Eugene W2HX > > > > > > > > -Original Message- > > > > From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] > On > > > > Behalf Of Scott Mace > > > > Sent: Sunday, May 15, 2011 10:07 PM > > > > To: time-nuts@febo.com > > > > Subject: Re: [time-nuts] basic question on GPS satellites > > > > > > > > What type of coax are you using and how long is the run? > > > > > > > > I live in the woods and my antenna is partially blocked by > > > > trees to the north and east and have never had problems. I have > about > > > > 130ft of LMR-400 between my antenna and splitter. > > > > > > > > Scott > > > > > > > > On 05/15/2011 05:30 PM, W2HX wrote: > > > > > Hi there. Recently acquired my first GPSDO. It is a datum 9390 > (thank > > > you, > > > > > Norm!). One aspect of its behavior seems strange to me. Within a > > > matter > > > > of > > > > > a few minutes, it seems that satellites are appearing and > disappearing. > > > > Are > > > > > the satellites moving that quickly? I might go from 1SV to 3SV or > 4SV > > > and > > > > > then a minute later go to 1SV or none. The antenna isn't moving > and > > > the > > > > > trees aren't moving too much today. I have not done anything with > > > regard > > > > to > > > > > setting minimum elevation or any other parameters. I did go > through > > > the > > > > > COLD RESTART procedure to clear out everything and let it start > from > > > > > scratch. > > > > > > > > > > > > > > > > > > > > Do other GPSDO users experience something like this? > > > > > > > > > > 73 Eugene W2HX > > > > > > > > > > > > > > > > > > > > ___ > > > > > 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-nut
Re: [time-nuts] Sidereal timekeeping
Antonio, it is quite easy to make an external circuit that uses a 32kHz xtal and divides it down to siderial seconds. It is also easy to drive most analog quartz clock movements from an external circuit. Just what signal do you need? What frequency? and what does it drive? (an alternate polarity quartz clock motor?) It can also be done with a micro if you have the skills. cheers, Neville Michie On 16/05/2011, at 8:02 PM, iov...@inwind.it wrote: The background of my request is an OT story. Just to mention briefly, I already have an ordinary (non-radio-controlled) clock machine which turns a miniature torsion balance in a sealed glass vessel. It runs on a single AA battery. No extreme accuracy needed. I wont to modify the rate to sidereal, and might have to replicate the setup too. I figure that the solution I should pursue is getting the "odd" crystals. Now it is clear to me that I have to explore two options, a) contacting a crystal manufacturer, b) modifying 32768 crystals. Thanks, Antonio hmur...@megapathdsl.net wrote: does anybody out there have any ideas as where to find a 32859Hz crystal (1/ 2 that value would be better) to be used to replace 32768 crystals in ordinary clocks? I think that 32768 crystals cannot be dragged that much. I've already read the JimLux article somewhere on the web, but I would be pleased finding a simpler solution. Also, I already have computer programs that show sidereal time. I think it depends upon what you mean by "ordinary clocks". Most of the recent wall clocks I've seen are battery powered (single AA) and resynchronize nightly via WWVB. If you want sidereal time, you won't have anything to synchronize to. What sort of accuracy are you interested in? If you want reasonable accuracy, you will need an external signal. (You can provide power over the same cable.) My straw man would be to send 32859Hz down coax or twisted pair and feed it into the xtal-in pin on the clock chip. I'm not sure how to set the time. You can cut the lead to the antenna to make sure it doesn't sync to WWVB. You can make 32859Hz from a PIC (or any micro you like) running off any handy frequency. Given that this is time-nuts, I'd suggest 10 MHz from a GPSDO. It might be simpler to dump the 32KHz and WWVB chip and drive the motor directly from a 1 PPS signal. Just use a sidereal second rather than a normal second. ___ 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] Sidereal timekeeping
The background of my request is an OT story. Just to mention briefly, I already have an ordinary (non-radio-controlled) clock machine which turns a miniature torsion balance in a sealed glass vessel. It runs on a single AA battery. No extreme accuracy needed. I wont to modify the rate to sidereal, and might have to replicate the setup too. I figure that the solution I should pursue is getting the "odd" crystals. Now it is clear to me that I have to explore two options, a) contacting a crystal manufacturer, b) modifying 32768 crystals. Thanks, Antonio hmur...@megapathdsl.net wrote: > >> does anybody out there have any ideas as where to find a 32859Hz crystal (1/ >> 2 that value would be better) to be used to replace 32768 crystals in >> ordinary clocks? I think that 32768 crystals cannot be dragged that much. >> I've already read the JimLux article somewhere on the web, but I would be >> pleased finding a simpler solution. Also, I already have computer programs >> that show sidereal time. > >I think it depends upon what you mean by "ordinary clocks". > >Most of the recent wall clocks I've seen are battery powered (single AA) and >resynchronize nightly via WWVB. > >If you want sidereal time, you won't have anything to synchronize to. What >sort of accuracy are you interested in? If you want reasonable accuracy, you >will need an external signal. (You can provide power over the same cable.) > >My straw man would be to send 32859Hz down coax or twisted pair and feed it >into the xtal-in pin on the clock chip. I'm not sure how to set the time. >You can cut the lead to the antenna to make sure it doesn't sync to WWVB. > >You can make 32859Hz from a PIC (or any micro you like) running off any handy >frequency. Given that this is time-nuts, I'd suggest 10 MHz from a GPSDO. > >It might be simpler to dump the 32KHz and WWVB chip and drive the motor >directly from a 1 PPS signal. Just use a sidereal second rather than a >normal second. ___ 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] Sidereal timekeeping
On Mon, 16 May 2011 00:01:54 +0200 (CEST) "iov...@inwind.it" wrote: > >Heh.. I cheated and used a 3325B to make whatever frequency we wanted. > >(even better, you can use GPIB to change the frequency vs time to make a > >"clock" that displays unusual things like "height above horizon" or > >"azimuth to orbiter") Whether this would be more useful than just > >driving a dial with a stepper motor is sort of a good question. > > If a 32859 crystal was easily available, that would be a fantastic solution. Such crystals are easily available. It's just that the usual suspects (digikey, farnell,..) do not sell them, as they have not enough volume. Easiest to get them is to call your local sales rep of a crystal manufacturer and ask him what options he has. Usually you can get away with buying a dozen or so of a custom frequency, at the cost of a couple USD each. If you can get one of the "tunable" types, you should be able to get single pieces at a reasonable price. Of course, the stability of those crystals is not time-nuts class, but <100ppm should always be possible and with a bit of tuning, you can get rid of that as well. Attila Kinali -- The trouble with you, Shev, is you don't say anything until you've saved up a whole truckload of damned heavy brick arguments and then you dump them all out and never look at the bleeding body mangled beneath the heap -- Tirin, The Dispossessed, U. Le Guin ___ 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.
