Re: [time-nuts] HP-58503A
Hi, The past week I had to replace more than 30 capacitors in various of my home electronics, some were bulged and others not so. There were 7 in a computer motherboard, 10 in other, 8 in a TV set power supply, 2 in an external USB disk power supply and the rest in other things, I know the grand total because I kept it together to test a cheap EMS meter against a LCR bridge. In my experience, all bulged capacitors are very ill, high ESR and very low capacitance, causing a lot of symptoms to appear (many of them intermittent). And when a capacitor bulges normally some or all of its neighbors are bad also, even without any external sign. I check them with a bridge and this is confirmed most of the times, so I suggest to replace the bulged capacitor and when you are there check or replace the others, they will bulge or burst in short time, high ripple currents and heat makes electrolytics the less reliable electronic components today. Best regards, Ignacio EB4APL On 02/01/2015 a las 14:34, Dr. David Kirkby (Kirkby Microwave Ltd) wrote: On 1 January 2015 at 17:03, Andy Bardagjy andybarda...@gmail.com wrote: Sounds like the GPS receiver is hosed. I think there are two different receivers used in the 58503a, unfortunately I'm away from my lab, otherwise I could check mine. It is a standard part, and may be available on the surplus market. Before replacing, I'd check the usual suspects, power supply health (look for failed electrolytics) and re-seat the gps board to board connector. Happy to measure things on my 58503a. The fact it originally failed with errors indicting the GPS receiver was not ok (nt Power- OK, OCXO- OK, EFC-OK GPS RCV-err. I, but later he can't communicate with the 58503A over RS-232, to me indicates the problem is not likely to be the just (if at all) the GPS receiver. As you say, power supply is a possible problem. I have a 58503A here that has a problem. Sometimes when power is first applied, the Alarm light stays on, and the log show power supply voltage errors. Yesterday I must have switched the thing on/off about 30 times before I managed to get the Alarm light to stay on. At the time I had a handheld DVM connected to the +15 V rail with the peak hold mode enabled. At least according to the handheld DVM, the +15 V rail was normal, so either the transient is too short for my handheld DVM to see, or the 85050A is reporting data voltage data incorrectly. Both are fairly like I suspect. I noticed a *very* slight bulge at the top of on a 100 uF, 400 V capacitor on the switch mode power supply. For various reasons, I am not going to change that cap now, but obviously a failed cap could cause this sort of problem. Dave ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] HP-58503A
Sounds like the GPS receiver is hosed. I think there are two different receivers used in the 58503a, unfortunately I'm away from my lab, otherwise I could check mine. It is a standard part, and may be available on the surplus market. Before replacing, I'd check the usual suspects, power supply health (look for failed electrolytics) and re-seat the gps board to board connector. Happy to measure things on my 58503a. Andy ◉ Bardagjy.com ◉ +1-404-964-1641 On Dec 30, 2014, at 12:35 PM, Richard Thorpe kisso...@gmail.com wrote: This list was recommended to me by the elecraft list. I have an HP-58503A sat disciplined “clock” that puts out a steady 10MHz to my K3 radio. Its been working 24/7 for years, I monitor it with David Anderson's Mac GPS Control X software on my iMac. Several days ago error messages showed up i.e.: Health- err, Self Test-err, Int Power- OK, OCXO- OK, EFC-OK GPS RCV-err. Its not tracking any sats and now I cannot event communicate with it at all even with a simple com program. Is there anyone out therE who can fix these things? Any suggestions would be appreciated. Thank you. Richard Thorpe K6CG ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Soekris without a GPS receiver.
From: Chris Albertson I think if you re-install any normal OS out of the box it will have the standard NTP included. Just get Ubuntu Linux then it will have ntpd already setup. Without PPS there is little point in having a GPS. These questions are best asked in the NTP mailing list. http://lists.ntp.org/listinfo = Chris, I completely agree with you. Were it possible to install a normal OS easily, I would have done so, but the device only has a CF card slot, and there is no secondary boot device, so you end up trying to install the OS on the memory stick image you have booted from, and this does not seem to work. In any case, nanoBSD is specially designed to minimise writes to the CF card, as it lives in RAM and not on disk. This is done as the number of writes to a CF card is limited, and hammering it with all the normal OS writes might result in a rather short lifetime. Agreed on the GPS as well - it's the PPS which is required for precise time measurement. David -- SatSignal Software - Quality software written to your requirements Web: http://www.satsignal.eu Email: david-tay...@blueyonder.co.uk ___ time-nuts mailing 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 Divider Board redux
I've been approached a few times in the recent past asking if I would do a re-spin of my frequency divider board. For details of this please see: http://www.perdrix.co.uk/FrequencyDivider/index.html It isn't viable to do this unless I can get orders for at least 40 and preferably more (the last production run was 100 units). At this stage I'm not requesting orders, but attempting to determine interest levels. If you would be interested in an re-run of these boards (possibly with some enhancements), please could you mail me OFF_LIST using the subject Frequency Divider and stating the number of boards you would want. The last boards from the previous production run (of 100) were selling at around GBP62.50 each EXCLUDING PP. (£75 including PP to anywhere). Fewer boards increases the cost (unfortunately). My email address is david dot partridge at perdrix dot co dot uk. Regards, David Partridge ___ time-nuts mailing 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] Soekris without a GPS receiver.
Hi I suspect that there are people on the Soekris list that could help you with an image for the box you have. Putting an OS image on it is not trivial, but it’s also not rocket science. It’s a bit easier with FreeBSD from the era that the box was new. Bob On Jan 2, 2015, at 2:49 AM, David J Taylor david-tay...@blueyonder.co.uk wrote: From: Chris Albertson I think if you re-install any normal OS out of the box it will have the standard NTP included. Just get Ubuntu Linux then it will have ntpd already setup. Without PPS there is little point in having a GPS. These questions are best asked in the NTP mailing list. http://lists.ntp.org/listinfo = Chris, I completely agree with you. Were it possible to install a normal OS easily, I would have done so, but the device only has a CF card slot, and there is no secondary boot device, so you end up trying to install the OS on the memory stick image you have booted from, and this does not seem to work. In any case, nanoBSD is specially designed to minimise writes to the CF card, as it lives in RAM and not on disk. This is done as the number of writes to a CF card is limited, and hammering it with all the normal OS writes might result in a rather short lifetime. Agreed on the GPS as well - it's the PPS which is required for precise time measurement. David -- SatSignal Software - Quality software written to your requirements Web: http://www.satsignal.eu Email: david-tay...@blueyonder.co.uk ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Soekris without a GPS receiver.
david-tay...@blueyonder.co.uk said: Chris, I completely agree with you. Were it possible to install a normal OS easily, I would have done so, but the device only has a CF card slot, and there is no secondary boot device, so you end up trying to install the OS on the memory stick image you have booted from, and this does not seem to work. ... I think the idea is that you do the install on some other system, using something like a USB to CF adapter. -- These are my opinions. I hate spam. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] HP-58503A
On 1 January 2015 at 17:03, Andy Bardagjy andybarda...@gmail.com wrote: Sounds like the GPS receiver is hosed. I think there are two different receivers used in the 58503a, unfortunately I'm away from my lab, otherwise I could check mine. It is a standard part, and may be available on the surplus market. Before replacing, I'd check the usual suspects, power supply health (look for failed electrolytics) and re-seat the gps board to board connector. Happy to measure things on my 58503a. The fact it originally failed with errors indicting the GPS receiver was not ok (nt Power- OK, OCXO- OK, EFC-OK GPS RCV-err. I, but later he can't communicate with the 58503A over RS-232, to me indicates the problem is not likely to be the just (if at all) the GPS receiver. As you say, power supply is a possible problem. I have a 58503A here that has a problem. Sometimes when power is first applied, the Alarm light stays on, and the log show power supply voltage errors. Yesterday I must have switched the thing on/off about 30 times before I managed to get the Alarm light to stay on. At the time I had a handheld DVM connected to the +15 V rail with the peak hold mode enabled. At least according to the handheld DVM, the +15 V rail was normal, so either the transient is too short for my handheld DVM to see, or the 85050A is reporting data voltage data incorrectly. Both are fairly like I suspect. I noticed a *very* slight bulge at the top of on a 100 uF, 400 V capacitor on the switch mode power supply. For various reasons, I am not going to change that cap now, but obviously a failed cap could cause this sort of problem. Dave ___ time-nuts mailing 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 doubler 5/10 and distribution amplifier for Lucent KS-24361
Hi, all, over the Christmas season, I have designed and built a frequency doubler from 5 to 10 MHz and a distribution amplifier for the Lucent KS-24361. A preliminary writeup is under http://www.hoffmann-hochfrequenz.de/downloads/DoubDist.pdf It features 4 or 5 10 MHz 10 dBm outputs and an optional 1PPS on SMA with CMOS levels into 50 Ohm. It is a small board to be mounted inside the KS-24361. Comments invited. regards, Gerhard ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
