[time-nuts] Beware the Casio WaveCeptor analog watch
Hello Time-Nuts, For many years I owned a Casio WaveCeptor digital watch and like it a lot. The down side was that the battery had to be replaced every few years. And since I had worn it for many years, the plastic case and crystal had taken quite a beating. Finally, the pin holder that secures the band broke - end of watch (except as a 'pocket' watch). So, I went out and bought a solar powered analog version of the WaveCeptor (and vowed not to take it caving). However, several months ago I needed to take an action at an exact time (not ebay) which was a miserable fail. I found that the watch was over a minute off. I went back and explored the watch manual and found that there is a procedure to sync the minute and second hands. I did this and after syncing to WWVB all was good. Now, a couple of months later I needed the precise time again. However I checked my watch before hand and found that it was 8 seconds off. Ahrg! It appears that the stepper motor position of the second and minute hands can be jarred out of sync with normal wear bumps and shocks. The trouble is you don't know when it happens (unless you check your watch against a trusted source often). Now I'm seriously considering buying a solar version of the digital watch to get rid of the problem. Regards, Skip Withrow ___ 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 TymServe TS2000 Manual now available
Hello Time-Nuts, Greg Dowd, one of the original engineers on the Datum TS2000 (and still with Symmetricom/MicroSemi), really came through! He found a CD with the TS2000 manual, and converted the Word Perfect file to a PDF. With his permission, I have uploaded the file to the KO4BB web site (it should currently be in the recent uploads section). It has now become obvious why I was having difficulty finding the serial commands to set up the unit, because there are none. The front panel menu is the only way to set the unit up. The only thing the serial port is used for is to output an ASCII string of the time once per second (that can be turned on and off). Regards, Skip Withrow ___ 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] Naked FEI FE-5650A
Well, Corby may have started something. I had the pieces to a Frequency Electronics FE-5650A lying around in a bag, so figured I would share as well. There are two photos. The first is an exploded view with the lamp (not dis-assembled) at the left. In the center is the microwave cavity with the filter and resonance cell (heat shrunk together) and the magnetic shield that goes over the whole assembly. At the right is the cover that goes over the cavity with the C-field coil inside. The second photo is the end view of the lamp assembly and the Rb cells turned on end. They are miniature (about 1/2" diameter) compared to the HP 5065A. Skip Withrow ___ 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] Curious, how many t-nuts have 5065A
Hello Time-Nuts, Pete Lancashire was wondering how many HP 5065As are out there. I don't know the exact number, but I know there are a lot. I think Corby (or someone) had a list of serial numbers at one time. I will confess that I do have one - and love it. It is a very old unit that doesn't have any updates other than a few new electrolytics and a finer adjustment on the C-field. Attached is a plot of it for the last three days. I have not touched it in several months. It is not in a particularly well controlled temperature environment (the yellow line on the graph), and it moved 110ns in three days (4.23x10E-13 frequency error). And most of the noise on the purple line (5065A frequency) is due to the GPS reference (NTBW50AA does not have a great antenna as indicated by the bottom GPS line). Skip Withrow ___ 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] Rubidium for HP 53131A
Hello Time-Nuts, A while back I acquired an HP 53131A, and a bit later added one of the Chinese knock-off 3GHz prescalers. Makes for a nice counter except for the very poor standard timebase. So, While researching the Option 010 and finding how outrageous the prices are running I found an Option 010 DIY project. It occurred to me that I could just substitute a Symmetricom X72 rubidium oscillator for the ovenized OCXO. It came out really nice (and is much better than an Option 010 - at least for anything over 10-100 seconds). I have a header so that I can calibrate the oscillator over the serial port (a one-time exercise I imagine). And I added a LOCK indicator in one of the removable plugs right above the reference BNCs on the back panel. Both the oscillator and the LOCK light are powered from the always on +12V so there is no warmup when the counter is turned on and the LOCK indication works when the counter is powered off. And since the fan runs 24/7 I'm not too worried about the X72 overheating. All the extra hardware is mounted on a simple 'L' shaped aluminum plate that bolts where the Option 010 mounts to the chassis side rail. I used a 16-pin flat cable that plugs directly into the 53131A main board. The only modification that was made to the stock counter was to drill the hole in the plastic plug for the LOCK light. Now the Reference Out can also be used to drive other devices as well (with reasonable accuracy). Relatively easy project that can be assembled in a weekend . Pictures are attached. Skip Withrow ___ 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] Looking for Datum TymServe 2000 (TS2000) manual
Hello Time-Nuts, After a very long journey trying to figure out the correct cable configuration between the AcuTime GPS antenna (receiver) and a Datum TS2000 I now have it working. Now I am in need of a manual so I can talk over the serial port. The protocol is apparently not the same as the TS2100. Any help would be appreciated. I'm more than happy to share the cable schematic if anyone needs it. It would be the same for Bancomm bc627 and 635/7 (?) as well as the TS2000. If you have any of these units you could probably use many different Trimble receivers (Resolution-T for instance) with RS-422 converter (though I have not tried it - yet). Thanks in advance for any help. Skip Withrow ___ 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 bc635VME/bc350VXI User's Guide - FREE
If any time-nut is in need of a bc635VME/bc350VXI Time and Frequency Processor 8500-0019 User's Guide Rev.B I have one for the cost of mailing. It's 8/5 x 11, and just shy of 1/4" thick. Includes setup and operation plus schematics and parts list. If you would like it please email me off list. Regards, Skip Withrow ___ 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] I've been thinking about a GPS receiver experiment
Hello time-nuts, I've been thinking about a GPS receiver experiment and just wondering if there are any opinions or prior experience that might save me a lot of time. What I have been thinking about doing is taking a GPS receiver (Novatel OEM4-G2) that has provisions for an external clock (5 or 10 MHz) and driving it with a rubidium oscillator (that has 1pps disciplining, (such as the X72 v5.05 or SRS PRS-10). The GPS even has settings for OCXO/rubidium/cesium dynamics. Then, (and here is the unknown part) what if the GPS receiver 1pps is used to discipline the rubidium? This basically forms a feedback loop, so could either hurt or help - depending. Supposedly the better oscillator would give a better GPS solution. And the better solution (1pps) should provide a better oscillator frequency. We know that GPS receivers using asynchronous clocks have 1pps errors and hanging bridges (OEM4 is spec'd at 20ns rms), If the oscillator is on 10MHz and disciplined will the 1pps error be reduced such as the Thunderbolt? Comments appreciated. Regards, Skip Withrow ___ 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] Weird GPSDO behavior - update
Hello Time-Nuts, Well, I think I know a little more about my GPSDO problem, but probably have more questions now than before. Thanks for all the replies to the first post with thoughts and suggestions. I first tried restarting Lady Heather and doing a cold boot on the NTGS50AA (then entering the same disciplining values). Same behavior. I let it run over the weekend and the same behavior happened on Saturday and Sunday morning. So, yesterday (Monday morning) I changed the gain to the gain of the oscillator (.0072Hz/V), damping to 1.2, and time constant to 900s. On the attached PRS10-2 plot you can see that it quickly settled. This morning, it looks like all is well from the plot (about an hour before the furnace kicks in at the right of the plot). HOWEVER, when the plot is expanded there is still funny business going on with the DAC control voltage at the same time of day. I just think the changed parameters limit the disturbance. The expanded plot is the attached PRS10-1. At this point I'm beginning to think that the NTGS50AA is the issue, but there are lots of questions left. 1. There are various version of the NTBW50AA/NTGS50AA GPS/operating firmware. Mine is 10.3 and I notice that it has the LH 'ro' designation (as does the 10.4 version). The 10.5 version does not give the LH ro notice. Maybe it behaves better with the disciplining? I will have to give a 10.5 a try. 2. Why does the glitch occur at 8am in the morning? Will have to try powering the NTGS50AA up at different times and see it the glitch moves around. 3. Which disciplining parameters are affected by this glitch and which are not? 4. Have other people seen this same behavior? Does it happen on Thunderbolts too? I'll update again when I have more data. Regards, Skip Withrow ___ 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] Weird GPSDO behavior
Hello Time-Nuts, I have a NTGS50AA GPSDO (close cousin to the NTBW50AA and Thunderbolt) with the OCXO removed and a SRS PRS-10 rubidium oscillator in its place. I have been running Lady Heather 5.0 and have changed the damping, gain, and time constant to give me a 20,000 second time constant with a damping of .6. I have attached a Lady Heather screen shot of the weird behavior. You can see that my GPS antenna is in a very none ideal location (window on the west side of the building). Once per day (about 8am) something disturbs the system. So, the GPSDO spends much of its time recovering and never gives me anywhere near the performance that this system is capable of. I would think that it is not the PRS-10 as it has no knowledge of time. I would also think that it is not the GPS system or receiver, since the GPS constellation repeats twice per day. Kind of the two things that I am left with are a glitch by the power company every morning (there is some large industrial machinery across the street (but then I would kind of expect glitches at 8am and 5pm), and perhaps Lady Heather doing something funny. This system has been running for quite some time, I have not tried restarting Lady Heather yet. Anybody seen anything like this, or have any good ideas? Thanks in advance, Skip Withrow https://www.avast.com/sig-email?utm_medium=email_source=link_campaign=sig-email_content=webmail_term=icon; target="_blank">https://ipmcdn.avast.com/images/icons/icon-envelope-tick-round-orange-animated-no-repeat-v1.gif; alt="" width="46" height="29" style="width: 46px; height: 29px;" /> Virus-free. https://www.avast.com/sig-email?utm_medium=email_source=link_campaign=sig-email_content=webmail_term=link; target="_blank" style="color: #4453ea;">www.avast.com ___ 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] How well does GPS work in the Arcitic?
Hello Time-Nuts,
I can attest that GPS works fine at the poles, though my experience was at
the South Pole. Every year the USGS goes to the South Pole to mark the
geographic pole. Since the ice is moving 10 meters per year at the pole
the pole appears to march across the ice.
One year ('97-'98 I believe) I took my GPS II and sat it on the choke ring
antenna the USGS had set up. It read S89°59'59" latitude. I was
impressed! We waited a bit to see if it would ever read 90° but it did
not. It just wandered around a bit. My speculation is that the math blows
up at 90° so it never goes there.
I have a picture of the event as well. If I get some time this evening
I'll have to scan it and post.
Yes, I agree that the HDOP is better at the poles and the VDOP worse, but
GPS works perfectly well anywhere on earth (for most purposes).
Regards,
Skip Withrow
___
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] Looking for OSA 3210 information
Hello time-nuts, I'm looking for a User Manual or Service Manual for the Oscilloquartz OSA 3210 cesium standard. So far my search has turned up nothing. TVB as a User Manual for the OSA3200, which I assume is an earlier (though similar model). The cesium unit is an OSA 3000 and any documentation on it would be a start. The unit that I have has an 8612 oscillator in it. Electronic copies would be great, but I'm always willing to pay shipping/copy costs for hardcopy. Thanks in advance. Regards, Skip Withrow <https://www.avast.com/sig-email?utm_medium=email_source=link_campaign=sig-email_content=webmail_term=icon> Virus-free. www.avast.com <https://www.avast.com/sig-email?utm_medium=email_source=link_campaign=sig-email_content=webmail_term=link> <#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2> ___ 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] Need information - CTS Knights JKTO-66 oscillator
Hello Time-Nuts, Anyone out there have ANY information on the CTS Knights JKTO-66 Frequency Standard? Seems that even Google has never heard of it. The particular one that I have is three boxes (battery, power supply, and oscillator in very large dewar) mounted on a 4U rack panel. BTW, the one I have belonged to WHBQ (back when it was owned by RKO), first station to ever play an Elvis record (1954). This unit appears to have a 1972 date code. Frequency was 11.73 MHz, close to 21X the 560kHz AM frequency but not quite. Any JKTO-66 information greatly appreciated. Thanks in advance, Skip Withrow <https://www.avast.com/sig-email?utm_medium=email_source=link_campaign=sig-email_content=webmail_term=icon> Virus-free. www.avast.com <https://www.avast.com/sig-email?utm_medium=email_source=link_campaign=sig-email_content=webmail_term=link> <#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2> ___ 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 5061A Cesium Beam Reference For Sale
Hello Time-Nuts, I acquired a number of 5061A and 5061B chassis (some with tubes, some without) plus a number of tubes - all in various states of unknown working condition. After going through the tubes to find working ones I have started to piece together working units. I currently have a 5061A working that is excess to my needs. I went through the chassis and replaced or repaired any non-functional modules, selected a random working tube (this one is very old, but is working fine), set the A11 oven temperature, electron multiplier voltage, hot wire ionizer voltage, loop gain, and 2nd harmonic level. And have set the C-field to put the unit on frequency (or nearly so, 95ns in 41.6 hr = 6.34x10E-13). I have the 41 hour plot that I can send to prospective buyers, as well as pictures of the unit. The 5061A has 5MHz, 1MHz, and 100kHz outputs (the 5061B adds 10MHz), but there is a 10811 oscillator in the unit that does have 10MHz coming out of it. This unit does have the battery option, but the battery is deader than a door-nail. There are no top or bottom covers, or rack mount flanges. I'm offering it to the time-nut community at what I believe is a reasonable price - $750 plus shipping from Denver, CO. If interested, please contact me OFF LIST. List member Paul Swedberg has a previously resurrected unit and he seems to be having fun with it. Thanks in advance. Skip Withrow ___ 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] E1938A
Hello Tom, There are two versions of the E1938A, one has a male DB-25 and one has a female DB-25 (mounted on the opposite side of the board as the male). Pinout and functions are the same between the two versions. If your hardware is expecting one type but all you have is the other an adapter cable can always be made from a couple of connectors and ribbon cable (been there, done that). Regards, Skip Withrow ___ 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] HP5061B Cold Start
Hello Donald & Nets, I have very much enjoyed the reports on your 5061 trials and tribulations. Many other time-nuts that have been fortunate enough to have a 5061A or 5061B have gone through many of the same exercises in bringing old units to life. I agree with your assessment that running the unit for as short a time as possible will extend the tube life as much as possible. I'm not quite sure that I agree that after one hour you have the full stability of the unit as it takes many hours (8-24) for it to reach thermal equilibrium. This doesn't mean that I run my cesium 24/7 either. I wish I had an infinite supply of tubes to do so. So, when I feel the use of the cesium is appropriate, I fire it up, wait a day or so if possible, then test away. Usually it runs a week or two, then I shut it down. The real purpose of the post though is to point out that using your cesium for only an hour a day is pointless. There are LOTS of alternative sources that should be used, that have better ADEV, at taus less than 5000 seconds. If you are making measurements less than 10-100 seconds in length use a good undisciplined crystal oscillator. In the 100 to 1000 second range, consider a good rubidium oscillator (they are dirt cheap compared to a cesium). It's really only those long tau measurements that your cesium brings something to the party, and this is what makes turning on your cesium so painful. If you are using it correctly, you are contributing to its eventual death. Another factor is the GPSDO. A good one is the best of both worlds, short term crystal stability, with long term GPS (steered cesium/rubidium) stability. I find that my cesium is most often used when I need to make oscillator measurements without the several nanosecond hits that the GPSDO takes from constellation switching, multipath, and other issues. For the most part, a GPSDO is my go to reference (but doesn't mean that I don't want my cesium handy). Keep up the good work. You have definitely caught the disease Regards, Skip Withrow > > > We performed an experiment with our working HP5061B which had been cold overnight. This was to better determine lock time from cold ovens. We found that the crystal oscillator oven heats up about twice as fast as does the cesium oven. Therefore the lock time is not much different whether the crystal oscillator was cold or hot. Our crystal oven has been running 34 when hot. The cesium oven has been running about 14 when hot. Here is our data as a function of measurement time in minutes versus meter readings. "+" denotes a pegged meter. The instrument was powered on at 0 minutes except for the cesium heater. The cesium heater was turned on at 13 minutes. The crystal oven had nearly stabilized by that time. Oscillator heater current was stable 15 minutes after power up and undershoots a bit at about 23 minutes. Note that first signs of beam current occur 7 minutes after cesium oven was powered up. First signs of 2nd harmonic occurred 9 minutes after cesium oven was on. We conclude that lock is feasible 23 minutes after a cold start. If the crystal oven is left on, lock can likely be achieved 20 minutes after the cesium oven is powered up. The ion pump preserves beam tube vacuum if the crystal oven is left on. If it is left off for long periods, high ion pump current may delay the application of power to the cesium oven until the vacuum is pumped down. For those who only occasionally need the stability of a cesium clock, you can have full performance 23 minutes after a cold start, or 20 minutes if the crystal and the ion pump are hot. If you use cesium for an hour a day, tube lifetime will be extended by 24 to 1 over continuous operation. If a beam tube lasted five years in continuous operation, it will last 120 years if used an hour per day. A similar benefit will occur if you use it continually for 2 weeks once a year. It does no good to waste cesium unless you are using the instrument. Time Ces Osc Beam 2nd 0 + 0 0 0 7 + 0 0 0 11 55 0 0 0 13 40 + 0 0 15 42 34 0 0 20 42 34 2 0 22 42 32 6 2 23 25 32 10 5 no lock 24 19 32 12 9 lock (free run back to OPR) 28 19 34 20 34 normal beam current ___ 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] Need HP 5061A setup help
Hello Time-Nuts, I have an HP 5061A (relatively new chassis) with a very old Cs tube installed (working) and I’m trying to wrap my head around the set up and calibration of this unit, and just hoping for some help. As a little background, HP changed the Zeeman modulation frequency, C-field intensity, and A1 synthesizer frequency at serial number prefix 1336A. This is detailed in CHANGE 20 (pages 7-9 and 7-10) Model 5061A Manual Changes in the 5061A Manual, and covered in much more detail in HP Service Note 5061A-9 (document 05061-9061 6/80-02). OLDNEW Zeeman frequency42.82kHz53.53kHz C-field 61 milligauss 76 milligauss Synth. Frequency12,631,771.6 Hz12,631,772.5 Hz I can put the tube on frequency at the new synthesizer frequency by changing the C-field current (closer to the old C-field value, by changing A15R19). 1. The Zeeman modulation frequency is a complete mystery to me. Is it related to the value of the C-field that you are running? 2. If you are comparing the unit to GPS to calibrate it do you really care what the Zeeman frequency is? Adjust the C-field to put it on frequency and call it a day? I’m not sure if there was a physical change in the Cs tube as well. But HP mentions that the new values should have better stability. 3. Would I be better off changing the synthesizer frequency back to the old value and adjusting the C-field (I would think lower) to put the unit on frequency? My first thought is to leave well enough alone. Thanks for any insight. Skip Withrow ___ 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] Austron 1150 Oscillator - Repair and Wrong Pinout
Hello Time-Nuts, I recently came across an Austron 2010B Disciplined Oscillator at a hamfest and couldn't pass it up. It was billed as working, but I figured the 1150 oscillator inside the unit was worth what I paid for it if nothing else. Thank you Ruslan for the help with the manual. So I proceeded to fire the unit up, and one of the first steps is to put the internal 1150 oscillator on frequency. Which, of course, wasn't going to happen. The trimmer was backed all the way out and it was still quite a ways off. So, time to open up the can of the 1150 and tinker. The 1150 is a nice oven controlled oscillator inside a glass dewar and is on 5MHz (this oscillator may have been made for Austron by Sulzer, or is a Sulzer design manufactured by Austron). I found a 10pF pad across the trimmer so removed that, semi assembled it, and fired it up. After a reasonable amount of warmup time the trimmer put the oscillator on frequency (yeah, or so I thought). After a few minutes it was off in the weeds again. It just wouldn't seem to stay on frequency. At about this point I decided to hook up the EFC and see if this made a difference. I had a copy of the 1150 data sheet, but the EFC pins listed didn't seem to match the hardware. I double checked with the 2010B wiring, and indeed the EFC is on pins 8 and 9 (the data sheet says 7 and 8). This led me to completely reverse engineer the 1150 schematic to check the EFC operation and oscillator operation. To make a VERY long story shorter, I discovered the root of my problem was with the oven controller. The heater control transistor wasn't shorted or open, but wasn't a transistor either. It would not shut off completely when commanded (very leaky I guess). The oven was slowly rising above the setpoint, but wasn't running balls to the wall either. This was the root of my continual drift. After replacing the transistor all is well, temperature is stable very near 70C, and the oscillator is well behaved and adjustable. Bottom line is - 1. The 1150 data sheet and pinout that I have seen on the net is WRONG. Pin 7 is the Oven Monitor, pin 8 is EFC (-), and pin 9 is EFC (+). My 1150 part number is 30294320. 2. I have a complete set of schematics, pictures of the inside of the unit, and data sheet. I'm very willing to share and hope to get a package together to upload to KO4BB.com, in the meantime if you need information feel free to contact me. Regards, Skip Withrow ___ 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] Need Autron 2010B Manual
Hello Time-Nuts. I am in need of an Austron 2010B Disciplined Frequency Standard manual. This seems to be a request that has been asked by others, and I think there are one or two out there (but I can't find any on the obvious web sites). Preference would of course be for an electronic copy, but I would be willing to pay postage costs both ways if you only have a physical copy. Perhaps I could get it scanned and posted to KO4BB. Any help or leads would be appreciated. Thanks in advance. Regards, Skip Withrow w - 303-790-1830 c - 720-320-8686 ___ 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] Higher resolution HP 5065A adjustment
Hello time-nuts, I have found that the frequency adjustment on the HP 5065A at 2x10E-12 is actually a little on the coarse side - at least for my well aged unit. So, I came up with a very simple modification which I think is an improvement. This change involves replacing the current adjustment with a 'fine' control (at 2x10E-14) and mounting the old control on the chassis as a coarse adjustment. 1. Acquire a 10K Knobpot like the 1K unit on the front panel (Bourns 3600S) and a 16.5K 1% resistor. 2. Unsolder the front panel knobpot and remove the 3/8" control nut and washers, then the knobpot. 3. Drill a 3/8" hole in the chassis and mount the old 1K knobpot (I used a location near the front panel and sort of behind the old location). 4. Place the 10K knobpot in the bracket on the front panel. Wire the 16.5K resistor to the 10K pot using one of the same numbered terminals that was wired before on the old pot. 5. Wire one of the previous pot wires and a wire to the old pot (use the same pins as previously wired) to the other terminal of the knobpot. 6. Wire the other previous pot wire and a wire to the old pot to the other end of the 16.5K resistor. Done. This should place the new 10K pot and 16.5K resistor in series across the old 1K pot. The old pot setting will be slightly higher to put the unit on frequency (it can be calculated if you like, or just measure and set the new value). The front panel control will now have a resolution of 2x10E-14. My unit seems to age higher in frequency, so you might want to start with the fine control around 750 (instead of in the middle at 500). Now you can happily chase the aging of your 5065A. I don't have a lot of data (or time) on it yet, but my guess is that it is in the low parts in 10E-13/day. Once characterized you should be able to dial in a value for aging (since last set) and be pretty darn close, or set it against your GPSDO. Once set, my unit will stay +/- 5ns for 24 hours when compared to GPS. Then the aging starts swamping the current setting, but it is fun having that kind of control. Regards, Skip Withrow ___ 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] Cs tube links
Hello time-nuts, Well, looks like Word does funny things with copy and pasted links. They all seem to link to picture 9 despite the number in the link. Just correct the number (9 through 12) and they work. Regards, Skip Withrow ___ 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] Have done some more cutting on the Cs beam tube
Hello Time-Nits, Ended up with a little free time and the saw nearby, so did some more cutting on the cesium beam tube today. Links to some pictures are provided for your enjoyment. 1. http://207.224.127.233/CsTube/CsTube9.jpg The first shot shows the new surgery. There is a U shaped metal shield around the microwave waveguide (the copper portion) and I removed a section from most of one side. This shield has the coil of yellow wire at the bottom. I also cut a window (removing the bottom and side) in the next shield out that is kind of a cross between a V and U shape. 2. http://207.224.127.233/CsTube/CsTube10.jpg <http://207.224.127.233/CsTube/CsTube9.jpg> The second shot shows the cut out shields again at a slightly different angle. The beam path is from the NW to the SE in the picture (north up). 3. http://207.224.127.233/CsTube/CsTube11.jpg <http://207.224.127.233/CsTube/CsTube9.jpg> The third shot shows the beam path pretty well. You can see the holes for the beam in the ends of the Y shaped waveguide (RF enters the bottom of the Y). You can also see another coil around the beam path, I take it this is the C-field coil. A think the coil around the bottom of the shield is the degaussing coil. The four wires that you see are the connections for these two coils. 4. http://207.224.127.233/CsTube/CsTube12.jpg <http://207.224.127.233/CsTube/CsTube9.jpg> The last shot shows the whole tube as it stands now. Now to find the time to cut a wooden base and fashion a couple of standoffs to set it on. Regards, Skip Withrow ___ 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] What to do with a 5061A/5061B with dead NiCds
Hello time-nuts, I have 5061A and 5061B units with the battery option and dead battery packs. My question is what makes the most sense when refurbing these units? 1. Yank the old battery out and just leave it that way. Running the unit on a UPS would preserve the functionality. 2. Replace the pack with a rebuilt NiCd pack. I'm sure Batteries Plus would be happy to do it, but sounds expensive. 3. Replace the pack with a NiMH pack, and really crank down the float current of the 5061. 4. Replace the pack with Li-ion battery. Would be a much smaller battery, but the charging circuit would have to be pitched. Building in a Li-ion charge controller sounds like it could be a project (which I don't necessarily want). 5. Yank the old battery pack and run the 5061 on two 12V batteries with an appropriate power supply/charger (basically a version of #1). Any thoughts on these or other options would be appreciated. Thanks in advance. Regards, Skip Withrow ___ 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] Need some wisdom from the cesium beam tube gurus out there
Hello Time-Nuts, I have been checking out some cesium beam tubes lately and have run into an interesting one. The tube is a standard HP 05061-6077 unit. There are two labels on these tubes, one at the end that has a serial number, and the other large label on the side that has the operating information (and the serial number). Problem with this tube is the large label is completely BLANK. It appears that there was never any information on this label. The source that it came from was pretty closely connected to HP, so it could be a tube that escaped before testing/characterization. The nice thing is that it works! Using some random nominal resistors for the oven temperature I get good beam current. Changing the electron multiplier voltage also dramatically changes the beam current. I see the 3 peaks around the on-frequency point quite nicely. So, the question is - how do I determine the operating point of the tube with no data? I could fire up a known tube and set the beam current for the same value, but how would the oven temperature vs. electron multiplier voltage be resolved. I would think that a lower oven temp and higher EM voltage would give the same beam current as a higher oven temp and lower EM voltage. I'm sure the HP did not do any characterization of the tube until it was all buttoned up. So how did they determine the temperature of the oven? Just from the value of the internal thermistor? I suspect the answer is what kind of S/N ratio do I want? If that is the case then I would be tempted to run at the lowest oven temp and highest EM voltage that gave me a usable signal - for the sake of tube life. Any thoughts? Thanks, Skip Withrow ___ 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] time-nuts Digest, Vol 148, Issue 28
Hello, 1. The comments in Lady Heather are placed there by Mark Sims. There are comments for all kinds of events during the year. 2. Yes, the output of the HP 5065A is 5MHz (and also 1MHz and 100kHz). I have a board from another HP instrument that multiplies 1MHz to 10MHz (there is no identification on the board other than an HP logo, at first I thought it was a 5MHz to 10MHz doubler, but the signal generator and spectrum analyzer set me straight). 3. I actually saw a 5065A recently that had a modification to decrease the C-field sensitivity. It had two 10-turn dial pots, the normal and another that was about 2x10E-14 per division. Unfortunately, I did not take note of the circuit to see how it was implemented. Regards, Skip Withrow On Tue, Nov 8, 2016 at 6:46 AM, <time-nuts-requ...@febo.com> wrote: > Send time-nuts mailing list submissions to > time-nuts@febo.com > > To subscribe or unsubscribe via the World Wide Web, visit > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > or, via email, send a message with subject or body 'help' to > time-nuts-requ...@febo.com > > You can reach the person managing the list at > time-nuts-ow...@febo.com > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of time-nuts digest..." > > > Today's Topics: > >1. Re: Thermal impact on OCXO (Scott Stobbe) >2. Re: Thermal impact on OCXO (Hal Murray) >3. Re: Subject: Re: I love the smell of tantalum in the morning > (Jeremy Nichols) >4. Re: Subject: Re: I love the smell of tantalum in the morning > (Charles Steinmetz) >5. This may be my new favorite old oscillator (Skip Withrow) >6. This may be my new favorite old oscillator (Mark Sims) >7. Re: This may be my new favorite old oscillator (Ruslan Nabioullin) >8. Re: This may be my new favorite old oscillator (paul swed) > > > -- > > Message: 1 > Date: Mon, 7 Nov 2016 16:47:28 -0500 > From: Scott Stobbe <scott.j.sto...@gmail.com> > To: Bob Stewart <b...@evoria.net> > Cc: Discussion of Precise Time and Frequency Measurement > <time-nuts@febo.com> > Subject: Re: [time-nuts] Thermal impact on OCXO > Message-ID: > <CALg-KtP_UN9qdXH7B-whmG1WHWrXPscLKRS+DhB2kUS9g4A_ > h...@mail.gmail.com> > Content-Type: text/plain; charset=UTF-8 > > Deeper into the rabbit hole :) > > I'm not sure what specific pic you are you using but most of them have at > least one timer that will run fully asynchronously and its timer input is > usually shared with one of the 32k osc pins. Which you can then use to wake > the prossesor from one of its sleep states. Do you end up hitting a clock > sync with the pwm block? > > Good old 74 series to the rescue. > > On Monday, 7 November 2016, Bob Stewart <b...@evoria.net> wrote: > > > Hi Scott, > > > > I wish I had some long term data, but I don't. I had initially set out > to > > build an accurate GPS frequency reference type of GPSDO. So, aging > wasn't > > an issue. It's either on and locked or it's not. So, I didn't worry > about > > leaving a unit running for months and collecting aging data. > > > > But then I had this crackpot idea of using the latches in a 7474 to > > stabilize the 1PPS from the receiver to the OCXO. Tom had a bit of a > > misunderstanding about what I was doing and we had a bit of a discussion > > until he caught on to what I was doing and its limitations. > > > > But, somewhere along the line, I realized that the idea was sound but my > > implementation was poor. The basic problem with using a timer in the > > dsPIC33 is that they use a PLL to generate the internal clock - even if > you > > supply a clock. That gives you a 1-count jitter in any output pulse you > > try to create. So, I realized that I could use the latches in a 7474 to > > latch the OCXO to the output of a timer on the PIC. With the PIC running > > at 40MHz, I have plenty of room for the jitter without the worry of a > phase > > slip. I think I've proved that that works, so now I have the possibility > > of using my system as a time server. And that means I now have to deal > > with such arcane matters as holdover, aging, and generating the time from > > the OCXO. The learning curve has been a bit steep. > > > > Bob > > > > - > > AE6RV.com > > > > GFS GPSDO list: > > groups.yahoo.com/neo/groups/GFS-GPSDOs/info > > > > > > ---
[time-nuts] This may be my new favorite old oscillator
Hello Time-Nuts, I recently acquired an HP 5065A rubidium oscillator (with 10811 10MHz OCXO). I think I pretty much have it running now and have been letting it cook for the last couple of weeks. I offset the C-field + and - and measured the frequency to calculate the C-field sensitivity. My unit came out to 1.96x10E-12 per dial unit, which agrees with the manual stated 2x10E-12. So, calculated the on frequency C-field value and dialed it in. Attached is a Lady Heather plot of the frequency over the last 3 days. The purple line is the 1pps plot with the vertical scale being 20ns per division. So, the unit is off about 125ns over the last 72 hours (running about 4.92x10E-13 slow). So my C-field setting is off about 1/4 of a division, but I think I'm going to leave well enough alone. The yellow line is the NTBW50AA temperature sensor, and you can clearly see when the furnace cycles. I was away for the weekend, and you can also clearly see when I came home this evening and turned up the heat. At the very end of the plot is the spike when I turned on the lights in the shop. I love using a Thunderbolt/NTBW50AA for making frequency measurements this way. I remove the OCXO, and insert the 10MHz from the DUT. Then disable disciplining so the DAC voltage doesn't try to chase the open loop oscillator. Of course the short-term performance looks worse than it actually is because of measuring against GPS, but the long-term measurements are very good. I want to log this unit at regular intervals to see what the aging looks like. Also need to do some measurements against the cesium to see what the short-term performance might be. But, I think this oscillator will be a good reference in many cases in lieu of using the cesium. Regards, Skip Withrow ___ 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] Cs tube pics
Hello Nuts, Yes, I originally had the wrong dash in the link names and did fix it almost immediately. That is why they now work. (Should have put pictures with both names in the folder so they would have worked for all) Tom, really like your third link that has the cover over the microwave innards cut away. I will have to do that, that way the cover won't be missing but you can see the copper cavity and C-field coil. Thanks for the other good links as well. Your pictures at HP are archived in Google somewhere, as I ran across at least one in my preliminary research. Regards, Skip Withrow ___ 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] So what’s inside that Cs Beam Tube anyway?
Hello Time-Nuts, I recently acquired a stock of dead cesium beam tubes, and my curiosity got the best of me, so I have cut one open. After watching lots of YouTube video of burning and exploding cesium I was a little leery at first. The first step was to make a very small hole just to let a small amount of air in, no flames or heat so I let it sit for a while for any reactions with air to take their course. Next I proceeded to cut off the ends, and after that the bottom of the unit, finally I trimmed the top off as far as I could. Pictures are linked below for your enjoyment. I have attached two of the before and after at low resolution. 1. http://www.rdrelectronics.com/skip/CS-tube/cstube1.jpg This is the before picture of a tube (not the actual one opened). It is HP part number 05061-6077. The band around the center of the tube is a mu metal shield that is removed by removing the screws along the seam. Unfortunately 11 of the 14 tubes that I received had the cables cut as shown (ouch!). 2. http://www.rdrelectronics.com/skip/CS-tube/cstube2.jpg This is a shot of the deconstructed tube. The cesium oven is on the left, the microwave cavity is in the center (under a metal cover), and the detector is on the right. 3. http://www.rdrelectronics.com/skip/CS-tube/cstube3.jpg This is the oven end of the tube. The oven (with the cesium) is the copper vessel. The ion trap assembly is at the top (with magnet). The first beam magnet is between the oven and the microwave cavity. One thing that I can say is that HP brought the art of spot welding to a new level. Note the stainless steel strips welded over the screw heads (and lots of other things). 4. http://www.rdrelectronics.com/skip/CS-tube/cstube4.jpg This is the detector end of the tube. I believe the hot wire ionizer is the broken metal strip. The electron multiplier/detector is in the metal box above it. The second beam magnet sits between the microwave cavity and the electronics at this end of the tube. I don’t think I broke the filament, this was probably the failure mode of this tube. Also note that all the wiring insulation is ceramic tubing, since insulation that out gasses in vacuum is a no-no. 5. http://www.rdrelectronics.com/skip/CS-tube/cstube5.jpg This is the bottom view of the tube for completeness. I have not yet removed the cover that is over the microwave cavity (and has the C-field coil around it). 6. http://www.rdrelectronics.com/skip/CS-tube/cstube6.jpg This is the top of the tube with the potting compound removed. I was surprised to find a couple of embedded resistors. I guess the good news is that it would be easy enough to remove the potting and solder on new wires if deemed useful. 7. http://www.rdrelectronics.com/skip/CS-tube/cstube7.jpg This is just a close-up of the broken hot wire ionizer (and all the spot welds). 8. http://www.rdrelectronics.com/skip/CS-tube/cstube8.jpg This is a close-up of the ion trap where the +3500V connects. I’m not a physics expert, but didn’t think about a magnet being involved. I don’t think any of the drawings that I have seen have ever mentioned it. So, enjoy. I will most likely be throwing the rest of the tubes up on ebay at some point. If there is strong interest in having them cut open first please let me know. I intend to cut up some wood to make an appropriate stand and add this one to my tube collection. Sorry for the long post, but I hope you found it informative. Regards, Skip Withrow ___ 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] Anyone looking for HP 5060A parts/modules?
Hello time-nuts, I have acquired three boxes of modules and parts to Hewlett-Packard 5060A cesium standards. As I don't have one of these units they are excess to my needs. Don't know if anyone still has one of these units ticking as they are quite old and cesium tubes have probably long expired. However, if you do have a need let me know and I will see if I can help. Please contact me off lest. Regards, Skip Withrow ___ 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 5065A questions
Hello time-nuts, I have recently had the opportunity to play with an HP 5065A rubidium standard and have some questions. This unit has been powered down for quite a long time, it appears to be almost working. I can see both the 137Hz and second harmonic signals but they seem very low. In the manual (the one from KO4BB.com) in section 3.9 (pg 3-1) there is a procedure to apply a 1A current through the TEC until the 2nd harmonic comes back (due to cell flooding). 1. What the heck is rubidium cell flooding, and how does the TEC in the 5065A fix this problem? None of the -many- rubidium oscillators that I have been inside before has a TEC, and I have never seen the subject addressed. The manual suggests that it may take several weeks at the 1A current to fix the problem (normal operation of the 5065A applies .7V across the TEC). 2. When the coarse oscillator control is swept across 5Mhz (open loop) the 137Hz ERROR signal swings about +/-8 on the meter. This seems low (and may be related to this flooding issue). Just wondering what others have seen on their units? 3. On page 5-15 of the manual it says to adjust A7R29 for a 2nd harmonic voltage of 4V at A14(1). In the section on A14 on page 8-61 the table states that the normal A14(1) voltage is 8V. So which is it? Granted the 2nd harmonic won't extinguish the CONTINUOUS light until it falls to less than about 1.1V. I'm also curious about the level of the 60MHz signal feeding the Rb cell. This unit has several volts of RF, which appears to be plenty, but just wondering if anyone has any baseline information. Also, any hints about the care and feeding of the HP 5065A would be welcome. Thanks in advance. Regards, Skip Withrow ___ 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] Symmetricom Power On Counter
Hello Time-Nuts, I just ran a Symmetricom X72 for 10 days to check the rate of the Pwr HRS counter. At one point I thought I did this with an SA.22c and found a discrepancy between actual number of hours run and the counter increment. I can report that the X72 does appear to count hours correctly. After running for 233 hours the hex counter incremented by 233 decimal. This leaves me with some questions though. The counter in the unit is four hex digits giving a max count of 2^16 or about 65,000. The life of the X72 is supposed to be about 20 years (roughly 180,000 hours). So what happens to the unit on overflow, does the counter just rollover? So how do you tell a new unit from one with 70,000 hours on it? And there is also a service bit that is supposed to switch when there are several months of life left, what drives this bit? Is it some kind of lamp life measurement (like the LPRO), and is the power on counter involved in any way? The Symmetricom X72 and SA.22c seem to be cousins, I have not played with an X99 and don't know if it is related. If someone has insight into these units I would be most interested in knowing some of the answers. In fact, the 'w' command dumps about 26 different values (all in hex) and having the secret decoder ring for what the item mnemonics are and the scaling of the displayed values would be very useful. The user manual lists the 'w' command but gives no information regarding the resulting display that I can find. Thanks in advance for any help. Regards, Skip Withrow 303-790-1830 ___ 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] Rare Symmetricom X72 with 1pps input available
Hello time-nuts, I have available a Symmetricom X72 rubidium oscillator with version 5.08 firmware. This firmware has the code to discipline the X72 to an external 1pps input. Unit has been checked out (including 1pps disciplining) and appears to be in good working condition. Oscillator comes with one of the adapter boards just like the non-pps units that we sell on ebay (check out auction 361567934794), pin-6 is jumpered to provide the 1pps to the X72 (pin 19). There is also a link to the manual in the ebay auction which has a lot more on the 1pps disciplining function. Yes, there are both pros and cons to the X72. Being very small its performance won't match an HP5065A. However, being very small makes it very portable, it has the GPSDO built in (damping can be set from 0.25 - 4.0, time constant can be set from 0 - 100,000 seconds), and power can be 10-32 volts DC. Unit is being offered for $225 and includes shipping to the U.S. First email to s...@rdrelectronics.com wins, I will send you payment information. If you miss this one and would like to be put on a waiting list please let me know, I hope to have more in the future. Regards, Skip Withrow RDR Electronics, Inc. 303-790-1830 <https://www.avast.com/sig-email?utm_medium=email_source=link_campaign=sig-email_content=webmail_term=oa-2322-a> Virus-free. www.avast.com <https://www.avast.com/sig-email?utm_medium=email_source=link_campaign=sig-email_content=webmail_term=oa-2322-a> <#DDB4FAA8-2DD7-40BB-A1B8-4E2AA1F9FDF2> ___ 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] FE-405B reprogramming
Hello time-nuts, I'm a little late on this discussion, but I too was very intrigued by the possibility of a 10MHz FE-405B. I have tried it and it is possible (maybe), there is still one big hurdle to get over. 1. There is a 15MHz crystal filter at the output of the 405. This was easily and cheaply replaced with a 10MHz unit. 2. There is a 15MHz (third overtone) crystal in the VCXO. This drives the DDS and the output. With some playing (new crystal and two component deletions) this was changed to 10MHz. BTW, this is not the 'good' crystal that is ovenized and gives the FE-405 it's really good numbers. 3. The DDS is normally 15MHz in, 5MHz (+/-) out that is locked to the 'good' crystal. So, it is reprogrammed to be 10MHz in, 5MHz (+/-) out. It works, kinda. The 15:5 ratio is enough to satisfy the Nyquist criteria and a normal 405 is happy. The 10:5 ratio creates some very interesting outputs from the DDS, There is a very large low frequency component that drives the PLL wacky. I suppose there are several ways to get around this problem, but I was looking for a way to change the unit with just minimal component changes. Doesn't look like that can happen I'm convinced now that the right way to do it is use a divider (regenerative or otherwise) to get there from here. Regards, Skip Withrow <https://www.avast.com/sig-email?utm_medium=email_source=link_campaign=sig-email_content=webmail_term=oa-2322-b> Virus-free <https://www.avast.com/sig-email?utm_medium=email_source=link_campaign=sig-email_content=webmail_term=oa-2322-b> <#DDB4FAA8-2DD7-40BB-A1B8-4E2AA1F9FDF2> ___ 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] One sure way to kill your FE-5680A or FE-5650A
We recently had a customer that purchased an FEI FE-5650A (basically a repackage version of the FE-5680A) and reported that it worked for several hours, then died. We promptly sent another unit, and he reported that it died as well. He had nothing but power hooked to the unit. On return of the first unit, it was examined and found to have corrupted code. The corrupted code problem was thought to be associated with doing bad things to the serial port (like framing errors), and we still believe this to be the case. However, the customer said only power was connected to the unit. I was asking some questions about how he was powering the unit, when he said he turned on the power supply (a large HP variable supply) and turned the voltage up to +15V (our 5650's are single supply). Ah hah, slowly ramping the voltage up on these oscillators appears to be a no no. The second oscillator has now been examined and it too was confirmed to have corrupted code. So, the word of warning is - DO NOT slowly ramp the supply voltage of FE-5680A and FE-5650A oscillators. I can't say what slowly is, but this guy was good at killing them. If I get some time I may try to repeat the results. My advice was to set the supply at 15V and just turn it off and on. I have not heard from him since. If anyone out there has a 5680A or 5650A that does not lock, the code issue is very likely the problem. I have seen several 5680 units as well as a few 5650 units with this problem. The good news is that they can be fixed. I would happily do this for any time-nut that has one if return postage is included with the unit. The bad news is that we don't know the nature of the code problem that trashes the software (stack overflow, error handling routine, etc.) so units can only be restored to their original condition that still has the bug in the code. Otherwise, the 5650 and 5680 are great values to get rubidium performance at very reasonable prices. I have 1000's of hours on them and 100's of power cycles, with a lot of serial port use, so if treated correctly they are reliable units. Regards, Skip Withrow RDR Electronics, Inc. <https://www.avast.com/sig-email?utm_medium=email_source=link_campaign=sig-email_content=webmail_term=oa-2322-b> Virus-free <https://www.avast.com/sig-email?utm_medium=email_source=link_campaign=sig-email_content=webmail_term=oa-2322-b> <#DDB4FAA8-2DD7-40BB-A1B8-4E2AA1F9FDF2> ___ 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] I thought GPS repeated every 12 hours (-2 minutes)
Hello Nuts, I am attaching a capture from Lady Heather of a 3-day run. You can see the temperature vary by 7C over each day. The TB is being run open loop and another GPSDO 10MHz input to the unit instead of the unit's oscillator. I expected the purple line to repeat every 12 hours based on the GPS constellation being the same (which maybe it kind of does), but there is definitely a 24 hour repeat. What is really weird is that the number of satellites that LH sees also repeats on a 24 hour cycle, not 12 (bottom trace). Any help in understanding this behavior? Thanks in advance. Skip Withrow <https://www.avast.com/sig-email?utm_medium=email_source=link_campaign=sig-email_content=webmail_term=icon> Virus-free. www.avast.com <https://www.avast.com/sig-email?utm_medium=email_source=link_campaign=sig-email_content=webmail_term=link> <#DDB4FAA8-2DD7-40BB-A1B8-4E2AA1F9FDF2> ___ 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] FE-5680A GPSDO controller also works with FE-5650A
Hello Time-Nuts, Nick Sayer's GPSDO controller will also work with the FEI FE-5650A rubidium oscillators as well. A small modification is needed to the board, but is rather trivial. First, the 5680 outputs 10MHz on pin-7 of the DB-9, the 5650 has a separate SMA connector. So, pin-7 needs to be lifted from the GPSDO board (the 5650 has the VCXO monitor on that pin). And a short coaxial pigtail needs to be run to ground and the GPSDO 10MHz input (I soldered the center conductor to the chip cap on the top of the board. I also just use an SMA coaxial Tee to run the 10MHz to my monitoring equipment. Second, the 5680 has an RS-232 interface and the 5650 is TTL. So, the 5650 can be modified for RS-232 (the pads are in the unit, the RS232 chip and 5 caps must be added), or the RS-232 converter can be taken off Nick's board and two small jumpers added. I have done both. I have asked Nick to add changes on the next pass of the board to accommodate these changes more easily. These mods assume a 5650 that RDR-Electronics has modified to have the same control word resolution as the 5680. I hope to publish some Lady Heather plots soon of the GPSDO performance. One nice feature is that Nick's code is open source and if people wanted to add features (such as the EEPROM write) it should be easy to do. I know I have had fun playing with the controller the last couple of seeks. Regards, Skip Withrow <https://www.avast.com/sig-email?utm_medium=email_source=link_campaign=sig-email_content=webmail_term=icon> Virus-free. www.avast.com <https://www.avast.com/sig-email?utm_medium=email_source=link_campaign=sig-email_content=webmail_term=link> <#DDB4FAA8-2DD7-40BB-A1B8-4E2AA1F9FDF2> ___ 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] A few more FEI FE-405B oscillators available
Hello time-nuts, I have a few more of the characterized Frequency Electronics, Inc. FE-405B oscillators available. These units have ADEV plots by Corby Dawson from 1 to over 1000 seconds. All the units have had the temperature compensation disabled (but it is easy to reverse if desired, though the unit does have to be opened). Power required is 5V and 15V DC, output is 15MHz sine, and they have the same serial interface as the FE-5680 rubidiums with a step size of 1.05x10E-14. After being on for a while aging generally seems to be in the very low parts in 10E-11 per day. ADEV for these units is generally some parts in 10E-13 from 1s to 100-1000s. Price is $200 each plus shipping. If you are interested in a unit I will send you the ADEV plot of the unit that you will receive. First come, first served with the best units going first. I also have one unit that is almost flat at 1.1-1.6 X10E-12 from 1 to 256 seconds. Will let this one go for $150 plus shipping. Payment can be with PayPal or credit card. Please contact via email at s...@rdrelectronics.com. Regards, Skip Withrow RDR Electronics, Inc. 303-790-1830 This email has been sent from a virus-free computer protected by Avast. www.avast.com <https://www.avast.com/sig-email> <#DDB4FAA8-2DD7-40BB-A1B8-4E2AA1F9FDF2> ___ 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] Trimble Resolution-T 52664-35
Hello Time-Nuts, I just had a learning experience with the Trimble Resolution-T, so I thought I would document it here and perhaps save time-nuts some time in the future. RDR Electronics has sold a number of telecom surplus Resolution-T units (p/n- 52664-35) and we recently had a customer that said he could not talk to the unit. I fired one up and, sure enough, found the exact same problem - no TSIP communications. After a little experimentation I found that I could communicate with the unit using Trimble GPS Studio and that the unit was in TEP mode (a Trimble emulation of the Motorola commands). Unit is also 9600,N,8,1 (instead of Res-T 9600,O,8,1 default). Apparently, the standard Trimble product is 52664-05. The -35 units identify as 'Timing Receiver' and have firmware 1.16. There is a time-nut archive that says you can change the mode to TSIP with GPS Studio, which I successfully did, however I could never make it stick. It seems that the Save Changes issues some kind of reset that always puts it back in TEP mode (before the TSIP mode is written to NVRAM). So, to solve this problem I downloaded the Trimble 1.17 firmware (upgrade from 1.14). It does successfully load into the -35 units (despite the many warnings in the documentation). It identifies as a Resolution-T now and defaults to TSIP at 9600,O,8,1. The units that we are listing on ebay will have the 1.17 firmware loaded into them (and will be tested). If you purchase units from other vendors with the 52664-35 part number be aware that they will most likely be in TEP mode (unless they specifically address this issue). Hope this information helps any prospective Trimble Resolution-T users. They are nice receivers designed for timing applications - 3.3V, 12-channel, 1pps, with sawtooth correction output. Regards, Skip Withrow This email has been sent from a virus-free computer protected by Avast. www.avast.com <https://www.avast.com/sig-email> <#DDB4FAA8-2DD7-40BB-A1B8-4E2AA1F9FDF2> ___ 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] 1st Batch FE-405B sold out
Dear Time-Nuts, Thanks for the enthusiastic response to the FE-405B units! All of the oscillators that Corby had characterized have been sold. People that requested multiple units will get one to start and have been put on the list for the next round, so that they could be spread as far as possible. I have several dozen more units. Will talk to Corby about characterizing another batch And will let the list know when more are available. Stay tuned. Regards, Skip Withrow RDR Electronics, Inc. 303-790-1830 ___ 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] Frequency Electronics, Inc. FE-405B Oscillator Availability
Hello Time-Nuts, RDR Electronics has a limited supply of FEI FE-405B OCXO oscillators with digital frequency control available. These are very good crystal oscillators that are generally BELOW 1x10E-12 from 1 to 1000 seconds (some approaching a couple of parts in 10E-13). The mediocre ones are in the 1x10E-11 to 1x10E-12 range for 1 to 1000 seconds (still very good). In addition, these units have digital tuning via a serial port that has a resolution of 1.05x10E-14 (no DACs involved, it’s done with a DDS)! These units have a DB-9 connector that is compatible with the FE-5680A and FE-5650A rubidium units (no LOCK or VCXO signal, of course). That’s most of the good news, the bad news is that these are 15MHz oscillators and cannot be changed. There is a 15MHz PLL and crystal filter that are the two largest hurdles. The ovenized oscillator in the unit is at 5MHz, but it is buried deep below all of the rest of the goodies that make these interesting. You can check out lots of FE-405B data on Tom van Baak’s website at http://www.leapsecond.com/pages/fe405/ . There are some slides at the end of all the graphs. You can check out pictures of the unit at: http://rdrelectronics.com/skip/dec/fe4051.jpg http://rdrelectronics.com/skip/dec/fe4052.jpg http://rdrelectronics.com/skip/dec/fe4053.jpg http://rdrelectronics.com/skip/dec/fe4054.jpg http://rdrelectronics.com/skip/dec/fe4055.jpg The jumping around has been solved. It is caused by uP temperature compensation that changes the DDS value based upon the oven heater current. This input to the uP can be grounded which drives the offset to the max value and it stays there. This is absolutely what you would want for a GPSDO so that you don’t have your control loop fighting the temperature compensation. My thinking is that this is what you would want for a reference oscillator as well, but we have left a few units unmodified. After running for a while the aging of these units gets down in the 1x10E-12/day range. In addition, we have set these units so they are reasonably on frequency (parts in 10E-10) with a 00 00 00 00 control value (same commands as the FE-5680 and FE-5650). The range of control values on the FE-405B is F7 33 33 34 to 08 CC CC CC. We have a VERY limited supply that have been characterized by Corby Dawson and his H-maser (thanks) and ADEV plot will be sent with the unit. They fall into three general groups: 1. Temperature compensation disabled, great ADEV (1x10E-12 to 1x10E-13 generally) 2. Temperature compensation disabled, good ADEV (1x10E-11 to 1x10E-12) 3. Temperature compensation intact, great ADEV (1x10E-12 to 1x10E-13 generally) I would like to offer these up to the time-nuts community. Asking $200 for Group 1 and 3 units, $150 for Group 2 units. Postage to the US is $7.10, we will ship international – postage is $26.50. I can send a copy of the ADEV plot for the unit you would receive via email before you decide to purchase if desired. Please send email to s...@rdrelectronics.com. Sorry for the long post, and the commercial nature (but it is exclusive to time-nuts at this point). Thanks, Skip Withrow RDR Electronics, Inc. 303-790-1830 ___ 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] Looking for Datum/Symmetricom MONITOR.EXE software
Hello Time-Nuts, Looks like the TLI interface on my PRS-50 has died (I just can't get anything through either serial port - 9600,8,N,1), and I need to switch the auxiliary output from its current 5MHz to 10MHz. When I remove the TLI interface I can see status over the rear RS-232 connector at 2400,7,O,2, so it looks like it is working. Trouble is, it looks like I need the old Datum DOS monitor.exe program to be able to talk to the PRS-50 now. Google doesn't seem to have been my friend, if anyone has it squirreled away I would very much appreciate a copy. My guess is that this software was used with the PRS-45 also. There is also a Windows program called Instrument Monitor that works with the 2400,7,O,2 interface, but doesn't seem to be able to change the auxiliary port or if it can, let me know how). The Monitor2, Monitor3, and Hyperterminal can only be used with the TL1 command language. I have copies of all of them (but are now useless). Thanks in advance for any help. Regards, Skip Withrow ___ 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] Surplus Rubidium Oscillator Frequency Spread
Hello time-nuts, As an experiment I took 10 FEI FE-5650A rubidium oscillators and measured their frequency error (units were chosen randomly). These were 15MHz units taken directly off the telecom cards with no modifications. These units never went to China, and are pulls from working systems. Each unit was allowed to warmup for a couple of hours before the measurement was made. Results were: Unit # Date Code Error 301302 0716 -2.87 x 10E-10 C312570 0839 +4.16 x 10E-11 79119 0701 -1.01 x 10E-10 C312324 0812 -2.54 x 10E-10 69008 0450 -2.52 x 10E-10 60495 0352 -6.05 x 10E-10 78894 0651 -4.30 x 10E-11 79287 0701 -2.77 x 10E-10 71379 0523 -1.80 x 10E-10 78871 0651 -8.58 x 10E-10 Date code is YYWW. The units with a 'C' in front are after production was moved to China. All but 1 of the units ran slow (my reference was a Trimble GPSTM, locked to GPS, so should be within a couple parts in 10E-12). I doubt that FEI's reference was off by a couple parts in 10E-10, so my conclusion is that they tend to age slower while in service (they are disciplined to GPS in the application anyway). These oscillators can be stepped by 6.8 x 10E-13 via digital control. When modified by us at RDR we set them +/-2x10E-11 (for a 00 00 00 00 control word). It would be interesting to know how many hours are on each of the test units, but I know of no way to obtain that information (unless it is part of the secret information that be read out of the unit). Regards, Skip Withrow ___ 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] bc620 / TS2000 to Acutime 2000 cable pinout?
Hello Time-nuts, I am trying to resurrect an old Datum TS2000 time server (which uses a Bancomm BC620AT card) and need the cable schematic for the interconnection between the time server and the Trimble Acutime 2000 antenna. The TS2000 uses a high-density DB-15 connector, the Acutime 2000 uses a 12-pin circular connector. I have the signal labels for both connectors, but don't know if I have the sense of the RS-422 connections correct. If someone has the cable schematic I could sure use it, the Datum and Bancomm manuals don't seem to address it. Thanks in advance. Regards, Skip Withrow ___ 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] SRS TSD11 Rubidium Oscillator
Hello Nuts, Anyone know what the differences between a SRS TSD11 and PRS10 are? From all outward appearances it looks like a PRS10, and at first glance it looks like a PRS10 from the inside. Has anyone seen a spec sheet (or manual) for the TSD11? Thanks in advance, Skip Withrow ___ 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] Symmetricom SA.22c rubidium oscillator information
Hello Time-Nuts, I have been playing with some Symmetricom SA.22c rubidium oscillators and wanted to pass on some of the interesting information that I have found. RDR Electronics has a large number of these units in stock. 1. These oscillators are pulls from telecom cards and are 15MHz when pulled. The ACMOS output can be changed in frequency to any value equal to 60MHz/2N where N=1 to 65536. We have been changing them to 10MHz when testing. 2. There is a 1pps output that is off in the pulled oscillator. During testing we turn the 1pps on. However, in the startup header it still reports as off, but it IS on. 3. The startup header reports the correct values for the xtal (60MHz), ACMOS (programmed value), and SINE (10MHz) outputs. However, if the 'i' command is later used these values are all wrong, there appears to be a bug in the software. Perhaps a hex to decimal oops, or something related. 4.There is an internal TIC (!) that can be read using the 'j' command. It has 16.7ns resolution. The second input is the 1pps input pin (pin 15). Over one second this is 1.67x10E-8, but sampling over longer intervals gives correspondingly higher resolution. It reads out in hex and seems to work well. There is also digital frequency control via the 'f' command (2x10E-12 resolution). So, with some software that can read and write a serial port a GPSDRO wouldn't be too hard. 5. There is also analog EFC if desired. 6. The SA.22c User Manual and three pictures of the internals have been downloaded to Didier's website. They will be available for download once they have been taken out of the upload area. 7. The Symmetricom X72 rubidium oscillator (smaller, and with 10-32V input) is a close cousin to the SA.22c, at least from a user software perspective. Hope this information helps for anyone that might have one of these, or is contemplating using one. Regards, Skip Withrow ___ 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] Questions regarding tuning Thunderbolt with Lady Heather
Hello Nuts, I have been playing a bit tuning a Thunderbolt with Lady Heather and now have more questions than answers. The collective time-nut brain would be appreciated. 1. Using the '' command I can change the damping and time constant in LH. Are these values immediately transferred to the TB? 2. Do I have to use the LH 'e' command to permenantly save new damping and time constant values to the TB? 3. After using the '' and 'e' command the lock-in behaviour of the TB does not seem to change. Is this normal behaviour? Is one set of values used when locking and the adjusted values used once it is phase locked? 4.Is there some way to read out the values stored in the TB? When I use the 'e' command on the TB, change values in LH, then restart LH and the TB I see the last values given to LH, and not what I thought was saved with the 'e' command. 5. If the TB is placed in hold mode and the DAC set to 0.0 volts it actually goes to 0.2 volts (min is at -5, max is at +5, and iv is 0.0 which it actually starts at on power up). Anyone know why? Thanks in advance for any guidance! Regards, Skip Withrow ___ 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] Wenzel 100 MHz Oscillators (w/ EFC) available
Hello time-nuts, Please excuse the blatantly commercial announcement, I generally keep business matters off the list, but I have some Wenzel oscillators that may be of interest to time-nuts and wanted to give you first crack at them. These are Wenzel 500-06769 units, custom number for Harris used in microwave radios. Output is 100MHz at +20dBm. Supply input is +12 volts DC (about 500mA at start). EFC runs between 0.5V and 4.5V with positive coefficient and is about 335Hz/V. Unit is in standard 2 x 2 x .75 package. Output connector is female SMA. These would make great units for synthesizer and DDS projects. I don't have the ability to measure the phase noise, but should be relatively good as they were used at microwave frequencies in their past life. I'm asking $50 each for them and $7 (any quantity) Priority Mail shipping to U.S. addresses only. If you would like one (or more) please PayPal to pay...@rdrelectronics.com. I have attached a picture of one unit with the pinout. Regards, Skip Withrow RDR Electronics, Inc. 303-790-1830 8am-5pm M-F ___ 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] Things your mother (or FEI) didn't tell you about FE series oscillators
Hello time-nuts, I have spent a lot of time recently with Frequency Electronics, Inc. (FEI) oscillators including the FE-5680A, FE-5680B, FE-5650A, and FE405B and just wanted to pass on some of my findings. Not everything I am including here is new, but figured I would include the informattion for the sake of completeness. As already known, there are a bunch of different variations on some of the oscillators. Here is kind of a quick rundown: 1. The 'old' FE-5650A - This unit used a 50.255 MHz VCXO and placed the synthesizer outside the physics PLL. This unit could be programmed over a wide range of frequencies and is great if you need an oddball output. The digital board in the unit has the two small pushbutton switches and the nearby 5-pin connector for serial communications. 2. The 'new' FE-5650A - This unit has the same physical construction, but the circuit functionalyity is quite different. It uses a 60 MHz VCXO and the DDS is inside the physics control loop. The output is divided from the 60 MHz. Many of these units that came from the telecom industry have 15MHz output. Unit has serial communications on pins 8 9 of the DB-9 connector. 3. The 'old' FE-5680A - This unit has a different physical footprint than the 5650A, but virtually the same circuit. Again uses the 50.255 MHz VCXO and has the programmable synthesizer that can be tuned over a wide range. Circuit board has the same two push botton switches and 5-pin serial connector. Many of these units only have a 1pps output (they came off Motorola cell boards). 4. The 'new' FE-5680A - This was the popular, inexpensive unit that was available a year or two ago. Unit uses the newer 60 MHz VCXO architecture and has serial communications via pins 8 9 on the DB-9. 5. The FE-5680B - This appears to be a VERY close cousin to the new 5650A and 5680A. It is in the 5680 physical package, but has a compact DB-15 (think VGA) connector. Unit only needs single +15V supply. 6. The FE-405B - This is a crystal oscillator that is the same physical package as the 5650A. It has a 15 MHz output. The interface is the same as the FE-5650A (except no LOCK signal), including the capability to communicate over the serial interface to change its frequency. TUNING THE NEWER UNITS Now for the new information. Tuning the units with the 60 MHz VCXO has been published (see the FEI document that is archived in several places) and uses several commands to read and write a 32-bit command value. However, only the tuning sensitivity for the FE-5680A has only been published that I am aware of. FE-5680A - The tuning sensitivity of the FE-5680A is 6.8126x10E-13 for the LSB. The command value runs the full range from 00 00 00 00 to FF FF FF FF. The value is 2's complement with positive values driving the frequency higher and negative values lowering the frequency. Larger values may unlock the unit and the positive and negative values may be different (depends on how well the VCXO is centered). FE-5650A - The tuning sensitivity of the FE-5650A is 1.4900x10E-17 for the LSB. Sounds great, but wait, turns out it does not have any more resolution than the 5680A. It takes a 45,722 step of the command register to step the DDS. So, it retains the same 6.8126x10E-13 actual minimum step of the oscillator. Also, the minimum value of the control register is F0 00 00 01, maximum value is 0F FF FF FF. FE-5680B - The tuning sensitivity of the FE-5680B is 3.7248x10E-16 for the LSB. Same situation as the 5650A above, but the are 1829 counts per DDS step. Minimum value is F0 00 00 01, maximum value is 0F FF FF FF, same as the 5650A. FE-405B - The tuning sensitivity of the FE-405B is in the neighborhood of 1.143x10E-14. Minimum value is F7 33 33 34, and maximum value is 08 CC CC CC. FINDING THE RIGHT TUNING WORD So, if you know how far off frequency your oscillator is divide that by the LSB sensitivity, convert the number to HEX, and load it to the oscillator (with the right + or - sense). Enjoy! Skip Withrow ___ 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] Any FE-5650A help our there?
Hello Nuts, Looking for some help with an FEI FE-5650A. This is one of the units that is surplus from the telecom industry with the Option 02 serial interface. Unit was working fine - locked, and was able to control the frequency by issuing commands to the serial port. Then something funny happened, oscillator went unlocked and cycling the power does not help. I have dumped what data I can (see attachments) and the software inside the 5650 appears to be corrupted. Attached are two files, one from a good 5650A and one from the bad 5650A. It appears that several of the data areas have been over-written with the 9-byte sequence 2D 09 00 24 00 00 00 00 24. This would be the response to the 2D query command, except the data in the frequency register was probably not 00 00 00 00 at the time of failure and 24 looks like the checksum for the header and is not the checksum for 00 00 00 00 (which would be 00). Is there an ex-FEI engineer out there in time-nuts land? Has anyone else seen such behavour? Is there any known way to reset the software for the 5650? Has anyone dumped the 5650 microcode (I vaguely recall one of the rubidiums having been dumped)? I took the processor board from a good 5650 and put it on the bad unit and it locks fine. My next step is to write a control word to the bad unit then read it back and see if it shows up in the memory dump, to see if the memory over-write is dynamic (the program has been premanently changed) or if it looks like it happened only once. Any information would be helpful, or suggestions on debug. Thanks in advance. Skip Withrow C:\Documents and Settings\Skip\My Documentsfe5680_info_win32 1 Cmd 0x22 0x0D byte reply: [22] [0D] [00] [2F] [44] [02] [11] [1D] [43] [FD] [7A] [B6] [38] Cmd 0x22 ASCII (.): D...C.z. Cmd 0x22 ASCII ( ): D C z Cmd 0x29 0x09 byte reply: [29] [09] [00] [20] [14] [DB] [CE] [18] [19] Cmd 0x29 ASCII (.): Cmd 0x29 ASCII ( ): Cmd 0x2B 0x0A byte reply: [2B] [0A] [00] [21] [AA] [55] [55] [55] [00] [FF] Cmd 0x2B ASCII (.): .UUU. Cmd 0x2B ASCII ( ): UUU Cmd 0x2D 0x09 byte reply: [2D] [09] [00] [24] [00] [FF] [FF] [FF] [FF] Cmd 0x2D ASCII (.): Cmd 0x2D ASCII ( ): Cmd 0x47 0x08 byte reply: [47] [08] [00] [4F] [21] [20] [00] [01] Cmd 0x47 ASCII (.): ! . Cmd 0x47 ASCII ( ): ! Cmd 0x53 0x07 byte reply: [53] [07] [00] [54] [AF] [00] [AF] Cmd 0x53 ASCII (.): .. Cmd 0x53 ASCII ( ): Cmd 0x57 0x56 byte reply: [57] [56] [00] [01] [51] [63] [00] [55] [00] [4A] [00] [3E] [00] [2E] [00] [1D] [00] [0C] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [2C] Cmd 0x57 ASCII (.): Qc.U.J. . Cmd 0x57 ASCII ( ): Qc U J . Cmd 0x59 0x56 byte reply: [59] [56] [00] [0F] [51] [78] [FF] [C1] [FF] [D8] [FF] [00] [00] [16] [00] [2F] [00] [AB] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [00] [5D] Cmd 0x59 ASCII (.): Qx./ . Cmd 0x59 ASCII ( ): Qx / Cmd 0x5A 0x0D byte reply: [5A] [0D] [00] [57] [16] [00] [00] [00] [F8] [0A] [00] [00] [E4] Cmd 0x5A ASCII (.): Cmd 0x5A ASCII ( ): Cmd 0x61 0x0B byte reply: [61] [0B] [00] [6A] [36] [32] [33] [34] [39] [00] [3A] Cmd 0x61 ASCII (.): 62349. Cmd 0x61 ASCII ( ): 62349 Cmd 0x65 0x07 byte reply: [65] [07] [00] [62] [51] [07] [56] Cmd 0x65 ASCII (.): Q. Cmd 0x65 ASCII ( ): Q Cmd 0x67 0x08 byte reply: [67] [08] [00] [6F] [01] [CC] [6C] [A1] Cmd 0x67 ASCII (.): ..l Cmd 0x67 ASCII ( ): l Cmd 0xF0 0x0F byte reply: [F0] [0F] [00] [FF] [44] [44] [53] [36] [30] [20] [34] [2E] [31] [00] [5E] Cmd 0xF0 ASCII (.): DDS60 4.1. Cmd 0xF0 ASCII ( ): DDS60 4.1 C:\Documents and Settings\Skip\My DocumentsMicrosoft Windows XP [Version 5.1.2600] (C) Copyright 1985-2001 Microsoft Corp. C:\Documents and Settings\Skipcd My Documents C:\Documents and Settings\Skip\My Documentsfe5680_info_win32 1 Cmd 0x22 0x0D byte reply: [22] [0D] [00] [2F] [00] [00] [00] [24] [2D] [09] [00] [24] [24] Cmd 0x22 ASCII (.): ...$-..$ Cmd 0x22 ASCII ( ):$- $ Cmd 0x29 0x09 byte reply: [29] [09] [00] [20] [2A] [BE] [27] [9A] [29] Cmd 0x29 ASCII (.): *.'. Cmd 0x29 ASCII ( ): * ' Cmd 0x2B 0x06 byte reply: [2B] [06] [00] [2D] [00] [00] Cmd 0x2B ASCII (.): . Cmd 0x2B ASCII ( ): Cmd 0x2D 0x09 byte reply: [2D] [09] [00] [24] [00] [00] [00] [00] [00] Cmd 0x2D ASCII (.): Cmd 0x2D ASCII ( ): Cmd 0x47 0x08 byte
Re: [time-nuts] new gps sat prn30 svn64
- 012,4,4.096000e+005,1.081600e+004,1.6134907007e+000 These values don't seem to be out of line with the other SV being tracked. Just wondering if the clock bias has drifted this far off and drift now 2 orders of magnitude worse than when you made your observations? Regards, Skip Withrow ___ 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] Symmetricom TimeSource 3000 3500 Question
Hello Nuts, I have a Symmetricom 3500 shelf minus GPS receiver. The 3xxx series looks like it uses a proprietary IF interface that shoots 18V up to the GPS receiver, and I don't know what comes down. There has to be data though since the box can report lat and lon. Don't know if there is also any frequency reference signal, but based on the function of the box you might think that there is. The physical interface is just a single piece of coax. Does anyone know what the 'proprietary IF interface' is? Does anyone have an extra GPS receiver laying around that they would like to get tid of (or where I could find one) for these boxes? Thanks in advance. Skip Withrow ___ 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] Looking for FE-5680B oscillators
Just wondering if any time-nuts have a stash of FEI FE-5680B oscillators that they would like to get rid of at a reasonable price? These units are very similar to the FE-5680A except that they have 15-pin high-density D-sub connector (VGA style). Almost all these units on the surplus market don't have a 10MHz output, just a 1pps. That is fine with me, the 1pps is what I want. Price must be reasonable, or else I will just use a GPS receiver with 1pps output. I'm looking for several units. Please contact me offline. Regards, Skip Withrow ___ 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] Cheap 9.8Mhz Sa.22c's
There is a crystal in the sa.22 that will determin what output frequencies are available for output. On the 9.8MHz and 10MHz versions it is 6X the nominal output frequency (58.x MHz vs 60MHz). The sa.22 can be programmed to output xtal freq/2N for n up 2^16 (IIRC, it's in the manual). Thus, you can change 15MHz units (found on telecom boards) to 10MHz (n is changed from 2 to 3). I have done this. But, you can't change 9.8MHz (found on different telecom cards) units to 10MHz. Regards, Skip Withrow ___ 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] Looking for Trimble 34310 oscillator information
Hello time-nuts, I'm wondering if someone in the group has information on the Trimble 34310 oscillator variations? These are used in the Nortel NTBW50AA GPSTM GPSDO modules, and I have seen T, C2, and V variations. Researching the archives I also found reference to a T2 version. At sometime I think someone shared some information on these, but I can't seem to come up with it. Any help would be appreciated. I would be interested in knowing if one is any better than another. The vast majority of them seem to be the plain 'T' version. Thanks in advance. Regards, Skip Withrow ___ 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] Anyone know how to remove Option H14 from HP 58503A?
Hello Nuts, I have an HP 58503A with option H14, the Even Second Output (which doesn't start operation unitil the unit achieves GPS lock), and would be interested in getting it back to 1pps. I have compared the unit to one with 1pps and can see no difference. There seems to be no jumpers that are inserted or removed, and the DIP switches are in the same positions (BTW, anyone know what they do?). Have not tried reverse engineering the schematic or started probing yet. Perhaps it is a memory location in eeprom that is access through some kind of diagnostic function? Any help would be most appreciated. Thanks in advance. Regards, Skip Withrow ___ 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] RFX GPSDO - Anybody played with one of these?
Hello Nuts, Just saw this mentioned in Circuit Cellar, just wonding if it really exists, how much they are asking, and if anyone has played with one yet? http://www.rfx.co.uk/pdfs/GPS_OCXO_1300_10_module.pdf Regards, Skip Withrow ___ 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] Trimble SCPI commands
Hello time-nuts, Does anyone out there have information on the Trimble SCPI commands for units manufactured for Nortel (such as the NTGS50AA)? I have a unit that has a DB-9 that talks SCPI. The *IDN and *CLS commands work, but I have not been able to get anything else out of it. I have not found the TSIP port in the unit yet (if there is one). Thanks in advance. Skip Withrow ___ 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] Anyone familiar with SR-620 repair?
You don't need expensive test equipment to find this kind of problem. What I use is a sheet of liquid crystal film with a transition temperature just slightly above your room temperature. Just lay it on the circuit board and you can find where the power is being dissipated (even if pretty small) by watching the colors change. I think Omega Engineering sells a 8.5 x 11 sheet for about $18 if memory serves me. I have used this trick many times and it works great to find shorted (bypass) caps. No disconnecting anything, no milliohm meters, no 4 or 5 digit voltmeters. Regards, Skip Withrow ___ 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] FE-5680A decoded - another piece of the puzzle
Hello Nuts, I've been trying to get the analog EFC to work on the FE-5650A (a very close cousin of the FE-5680A). On these oscillators it is normally on pin-8 of the DB-9 (Option 12 and 30). As one of the serial lines is on this pin, I traced the jumper that is placed for the EFC option(s). However, changing the voltage on the pin does not seem to move the frequency (or at least not very much if it does). Anybody know the nominal EFC sensitivity of the 5680? On tracing things further, I have found that this input goes into the (4 channel) A/D associated with the microproccesor. Changing the voltage gives a value in message 5A that also changes a corresponding amount. The EFC bytes are bytes 5 6 of the 5A message, first byte is low second byte is high. Appears to be 12-bit value (0FFF max). The question is - how do you enable the EFC? Maybe it is a bit that has to be set in one of the other messages. (But then how does the uP communicate the EFC value to the physics package?) It (more likely) may be that I have not found the true C-field control circuitry yet and the A/D is just a monitor. I recall someone implementing C-field control on a FE-5680A with the pot disabled, but cannot find it now. If someone can point me to that post I sure would appreciate it. Thanks in advance. Regards, Skip Withrow ___ 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] New unit of time measurement
Dear nuts, I would like to propose a new unit of time, the 'textsecond'. This is the interval of time from the time the signal light turns green to when the driver behind the idiot texting driver honks their horn. Still collecting data on its exact length, but seeing a lot more examples lately. I'm sure there is probably a much more clever name (and there are a lot of clever time-nuts out there). However, I don't want this comment on social behaviour to blossom into a lengthy OT thread. Regards, Skip Withrow ___ 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] Looking for information on EGG TS-RFS Rubidium Oscillator
I have just come across an EGG TS-RFS Rubidium oscillator and have never seen any information on it. There is a 16-pin connector that is relatively well labeled, but some of the interface signals are still a mystery (like what is the range of the 'DC light', and what is the interface to the 'lock monitor' signal - also, what is 'REG MON'). Anyone with a manual for this one? Or any other knowledge. Google seems to be pretty devoid of information. Regards, Skip Withrow ___ 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] Looking for info on ERC-130
I'm looking for info on an Electronic Research Corporation model 130 reference. This is a 10Mhz rubidium reference. I know nothing about this unit, any comments on its goodness/badness would be welcome. Technical information seems to be non-existent, checked all the usual suspects for a manual and came up with nothing. Anyone out there with a manual? Thanks in advance. Skip Withrow ___ 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] Need help with Motorola OnCore software
Hello fellow nuts, I am trying to communicate with a Motorola UT+ receiver. Used to do it with the Motorola GPS software running in a DOS window on a PC running windows XP. Recently moved to a new machine (server, running XP again), but absolutely cannot get the software to run. I'm convinced that it has something to do with the communications startup. This machine does not seem to have a MS Dos tab, so am starting DOS from the Cmd line in the startup menu. I'm running GPSCOMMS from the \GPS directory and then starting GPS (from the \GPS directory). The window comes up and when the GPS receiver is initiallized it seems to send back the datum it is using. After than, nothing. I do know that commands are getting to the receiver, I have looked at the line on the Oncore with a scope (but haven't checked to see if it is at the right baud rate yet). Also still need to check to see if there is a respone from the UT+. I get the impression that the serial port may not be configured correctly (but how do I know with the GPS software?). Anybody know the tricks to running the old Motorola GPS program on a Windows machine? Is there better software out there that would be compatible with the OnCore UT+? Any help appreciate! Thanks in advance. Skip Withrow ___ 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] MCL Antenna Splitter
Hello Time-Nuts, Check out ebay auction 360303616823 for one of the Minicircuits antenna splitters. These units are pulls from telco equipment and will feed power from both/either side. I haven't hooked up a DC block (to protect the signal generator) so haven't measured the gain through the unit, but from the part number looks like it might be 3dB or so. Regards, Skip Withrow ___ 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] Looking for PTS-310 Manual
Hello nuts, I am in search of a PTS-310 manual. I know that Nigel GM8PZR has a PDF copy, but have been unable to find an email address. So, Nigel if you are listening would you mind sending me a copy. I believe my email will suck up large attachments. Also if anyone else has a copy or knows an archive that might contain the manual I would appreciate hearing from you. Thanks in advance for the help. Regards, Skip Withrow ___ 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] GPIB help
Hello Time-nuts, This could be opening up a can of worms - but here goes. I need some help/direction with programming my 5370B over GPIB. I have NI GPIB-ENET/100 and have install NI's Measurement and Automation software. All is good, the software sees the instrument and I can issue commands and get responses back. So far so good. Now the tricky part. I would like to write a program that collects TI values to feed to TVB's ADEV program. First I should ask - is there one out there that someone is willing to share? Being that I'm pretty ancient in the programming world and have not caught up with VB or C. So, I have been trying to write a BASIC program and use direct access to the gpib-32.dll. It has been very frustrating! I can seem to get the global addresses of the ibxxx functions, but no luck on getting error and status information back (iberr, ibsta). For example: SYS LoadLibrary, GPIB-32.DLL TO gpib% SYS GetProcessAddress, gpib%, ibdev TO ibdev% seems to return an address for the ibdev function. But, SYS LoadLibrary, GPIB-32.DLL TO gpib% SYS GetProcessAddress, gpib%, iberr TO iberr% does not seem to return the address of the iberr global variable. Any help appreciated. Thanks in advance. Skip Withrow ___ 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] Poor man's frequency distribution system
Hello time-nuts, Just a heads-up on one possibility for frequency distribution. Check out ebay auction 300359209544, it is a 16-way RF power divider for 1-30MHz. Put a 12dB amp in front of it and you have 16 outputs from a single source. Works great with a thunderbolt, I use one to feed several counters, synthesizers, and the spectrum analyzer. 40dB isolation between ports. RDR has a number of these units in stock. Regards, Skip Withrow ___ 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] Can anyone spare an LPRO lamp?
Hello time-nuts, I have an LPRO-101 that won't lock, so popped the cover and started poking around. The lamp was not lit, both physics packages were hot, and there was RF going to the exciter coil. So, I pulled the lamp and swapped it with another unit. The lamp from the good unit lit right up, so my conclusion is a bad lamp. The bad one is clear, the good one is slightly brownish. Anyone have a lamp that they would part with for a reasonable price? Thanks in advance. Skip Withrow ___ 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] 7614A Cesium Beat Tube variation
Hello Time-Nuts, The Datum 7614A/075 CBT is the standard version, and the 7614A/076 is the high performance version. I have a 7614A/077 - any ideas on what flavor this one is? Does a manual/schematic exist for the Datum (Symmetricom) 4201A? Thanks in advance for any help. Regards, Skip Withrow ___ 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] Looking for Datum (Symmetricom) 5045 Cesium information
Hello Time-Nuts, Anyone know of any information on the 5045 Cesium module used in the Datum PRS-50 (User Manual, Service Manual, etc.)? I did a cursory check of the Symmetricom web site but didn't turn up anything. Regards, Skip Withrow ___ 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] Acutime GPS Connector Update
Just so the information is archived somewhere, here is an update on the Deutch connectors for Trimble Acutime and Palisade GPS receivers. The Deutch MMP series of connector is no longer available and has been replaced by the IMC series. The mating connector body to the GPS receivers is IMC26-2212X. The female pins are part number 6862-201-22278 (this number did not change). The backshell for the connector is believed to be part number IMC2AD. These Deutch connectors are distributed in the US by Ladd Inc. (www.laddinc.com), phone is 800-223-1236. They will do small quantities and take credit card orders. Regards, Skip Withrow ___ 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] Source for Trimble Acutime 2000 Connectors?
Hello Time-nuts, I'm looking for the connector to mate with a Trimble Acutime 2000. The connector part number is Deutch MMP 26C-2212S1, pins are 6862-201-22278, and back shell is 6810-204-2001. I've tried the usual - Mouser, Digi-Key, and Newark. Who is their distributor in the US? I would even take a used connector cut-off (or not cut off the cable even) if someone had one laying around the shop. Any help appreciated. Regards, Skip Withrow ___ 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] Maximizing Cs Tube Life
Hello Time-nuts, Just wondering what the group concensus might be concerning maximizing Cs tube life. On one extreme, if a tube is not used at all it will lose its vacuum. That is why Symmetricom instructs that stored tubes be powered for at least 30 minutes each 6 months. At the other extreme is powering the tube 24/7 which depletes the Cs source. In the middle is the question of how long does it take to achieve satisfactory stability to use the unit to evaluate other devices (oscillators - xtal or Rb). I would like to maximize the tube life and only need to do evaluations periodically. My first inclination is to fire up the cesium a week or so in advance of use and then shut it down until needed again. Just wondering what the time-nut collective experience might be? Regards, Skip Withrow ___ 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] Loosing for Datum/Symmetricom PRS-50 Information
Is there a time-nut out there with any information on the Datum PRS-50 Cesium Primary Reference Source (spec sheets, User's Manual, command set)? I can find a reference to the user manual on the Symmetricom site, but when I click on it all that comes up are other User Manuals with the PRS-50 missing. Thanks in advance for any help. Regards, Skip Withrow ___ 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] Austron 2100 Antenna
I have run an Austron 2100 for a long time with a home-made antenna consisting of a short (15') vertical wire with an active impedence transformer at the base. It is just a FET source follower where the wire drives the base and the source drives the coax to the receiver. Power is fed up the coax via a home-made power inserter. A longer wire would probably work better, but it is pretty simple. I have the schematics somewhere, but would have to dig for the file. Regards, Skip Withrow ___ 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] Worlds smallest pendulum clock (oscillator)
Check out this device - http://www.sitime.com/products/sit3701.php Wow, a MEMS oscillator that works from 1 to 80MHz. This sounds like a candidate for constructing the worlds smallest pendulum clock (well I guess more tuning fork than pendulum). I'm sure some time-nuts have ideas for suitably small displays. Just food for thought. Regards, Skip Withrow ___ 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] Data Precision 8200 Voltage Standard
Realize a voltage standard post might be a little off-topic, but have seen them discussed quite a bit, so here goes. We have a Data Precision 6-1/2 digit voltage and current standard, which seems to operate except for the function of the front panel voltage selection. The mode and +/- voltage switch work fine. We do have the service manual, and the switches are read by the microprocessor. After checking the signals associated with the switches (read signals are generated by the uP, and read back on the data bus) my best guess is the the uP code my not be working correctly. The processor in this unit is a ROMed R6500/1 (cousin of the 6502). I fear that perhaps a bit in the ROM is being read incorrectly (in the switch read routine). My guess is that there is no way to read the code out of this part. If any time nuts have a parts unit laying around I would like to try swapping the processor to confirm my theory. My next check will be to adjust Vcc up and down and take some freeze spray to the processor to see if I can find a point that it will operate, however, that will certainly not provide a fix. Any help appreciated. Skip Withrow ___ 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] NIST Time Frequency Seminar
Hello Time Nuts, I recently became aware of the NIST Time Frequency Seminar coming up shortly and looked it up as it sounded interesting (to a time-nut) and is almost in my back yard (well, at least commuting distance). You can check out the web page at http://tf.nist.gov/timefreq/seminars/TFoverview.html. It all sounds very cool, UNTIL YOU CHECK OUT THE PRICE! Sure, I could see $300-$400 (which would still be pretty rich for my budget), but $1900? Obviously our tax dollars are not subsidizing this function. If anyone knows how to procure a discounted registration I would be most interested in hearing from you. Regards, Skip Withrow ___ 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] Need Austron 2110 manual
Hello Time-Nuts, I am in need of a manual for the Austron 2110 Disciplined Frequency Standard. Anyone have an electronic copy? I have already tried KO4BB's site and BAMA. I would be more than happy to pay shipping so that I could copy/scan a hard-copy if you have one. Guaranteed to be returned promptly. Regards, Skip Withrow ___ 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] FEI FE-5680B pinout?
Looks like I have uncoverd another version for the FE-5680. This unit is marked FE-5680B, and has a high-density DB-15 connector (like computer video). Manufacture date looks like 2004, FEI p/n is 261600-51604. Anyone have a clue as to pinout? Thanks in advance. BTW, Google search of FE-5680B produces abosutely zero results (as does looking at the FEI website). Skip Withrow ___ 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] Anyone with information on STLN4096A / HP Z3817 ?
Thanks for all the time-nut information on the McCoy OSC92 pinout identification, it indeed does appear to be the same as the Isotemp OCXO134. Now for the next time-nuts challenge. I also have a Motorola STLN4096A. It appears to be an oscillator used in some kind of telecom equipment. The really neat part is that it contains an H-P E1938A (I also know that some versions also came with the FEI 5680 rubidium)! The E1938A has the DB-25 on the other side of the board (and opposite sex) than the one sent to me by Rick K., but some work making a jumper and it works in my Shera GPSDO just dandy. The other two boards in the three-board set are also H-P and marked with a Z3817-x part number (one is the power supply board and one is a processor board). Now for the time nuts help. Any information on this beast? There are two DB connectors on the unit, the DB-9 (marked MMI) is RS-232 and seems to talk SCPI. Anyone have the command set? Is this a repackaged Z3815? The other connector (DB-25, marked TIB) is to the power supply board. I have identified the (18-36V) power supply pins, but there are other I/O's - including a 1pps. And I would imagine the 10MHz out. Does this unit also interface to a GPS receiver and is it already a GPSDO (minus the GPS receiver)? As always, thanks in advance. It is amazing the depth of knowledge of the collective time-nuts community. Regards, Skip Withrow ___ 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] Anyone have McCoy OSC92-100B data?
I have acquired a nice 10 MHz oscillator, but have absolutely no data. Model is marked as a McCoy OSC92-100B, it is rectangular 3x2x1.5 with six leads out one side. Does anyone have the pinout, operating voltage, EFC voltage for this unit? Thanks in advance, as always. Regards, Skip Withrow ___ 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] Austron 2100 Loran-C Frequency and Timing Receiver
Hello Time-Nuts, Well, my Austron 2100 seems to have bit the dust. The indication of trouble is that the 1pps light quit blinking. After some debug it appears that all the hardware is working (I have the manual with schematics) and that it is not getting a software pulse that diddles a flip-flop. There are some software diagnostic routines in the box. The RAM test runs fine, but it appears that I get an error on the EPROM test. The test generates an E-20 error. The book states that if the EPROM test fails it will give an E-21, but nowhere do I find any hint as to what an E-20 error is. I suspect that perhaps I have a corrupted EPROM. Most of the code appears to be working properly (front panel display and buttons work, it will even lock to Loran). There are three 2732A EPROMS, but no indication as to the checksum on the devices so can't verify if one is bad. Is there a time-nut out there with an Austron 2100? I would like to get a copy of the EPROMS or the code in them to check my unit. Even the checksums would help (given that the firmware revision is the same). The boards are very easily accessed from the front panel and the unit doesn't even have to be taken out of the rack. I have the capability to read and program the devices. Thanks in advance for any help with this oldie, but (was) goodie. Skip Withrow ___ 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] Help with Datum/Symmetricom TymServe TS2100
Hello time-nuts, I have recently acquired a Datum TS2100-IRIG NTP time server. Nice unit, and I do have IRIG-B to feed it, however, reading the manual I notice that there is a GPS version as well. Upon taking the top of the unit off I notice that there are the connector and standoffs for both Oncore and Trimble ACE-III sized receivers. Tried plugging both in, but the unit does not seem to recognize it (always reports GPS receiver busy). I tried calling Symmetricom (talked to Larry Dearing) but seem to be caught in a Catch 22. They will not release the information on how to make the change, and will not do it themselves since the product has been obsoleted. Anyone have a sympathetic contact at Symmetricom? Does anyone have a TS2100-GPS that they wouldn't mind taking the top off and spending a few minutes on the phone (303-790-1830 8am-5pm M-F)? There does appear to be some jumpers on the board, and there are also words in EEPROM that can be modified via terminal interface. Also notice that there is an LPRO rubidium option for these units. I have one of these too and would be interested in trying to upgrade to rubidium as well. Anyone with one of these units out there? Thanks in advance for any help or direction in finding answers to these questions. Skip Withrow ___ 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] FE-5680A adjustments
Dear time-nuts: I have several FEI FE-5680A rubidium oscillators running and am looking for any alignment information that might be available. I can successfully communicate with them via the serial port and can control the DDS to change output frequency. However, there are several pots and many test points on these units. Just wondering if an FE5680A guru would mind sharing some information? Also, is there any kind of EFC voltage control for the C-field (to use one as the oscillator in a GPSDO)? Thanks in advance for any help. Regards, Skip Withrow ___ 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] Need help with TrueTime GPS-XL 600-101
Greetings time-nuts, I have a TrueTime XL-AK (model 600-101-1) GPSDO that requires an antenna-mounted down-converter (I'm pretty sure). Of course, it is still on the building from the previous owner of this unit and cannot be made available. The manual does not seem to be of any help either - no block diagram or description of the conversion scheme. So, any help with understanding this unit would be greatly appreciated. Or, if you have a source for one of these down converters I would definitely consider purchase. The receiver module in this unit is a Trimble and the board seems to be marked 22880 at several places. Thanks in advance for your time. Skip Withrow ___ 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.
