Re: [time-nuts] 5370B Question / help needed
Hello Folks, I'm coming back to this after a few days of prodding etc. and there has been some progress. The fault has been tracked down to the A3 input board and it points at a crack in the board or a joint. Here is the sketch: After a good clean of the switches and re-seating all boards etc. the 5370 sprung back into life with almost-in-spec performance of 102.xx ns with it's own 10 MHz. Trouble is it didn't last - after a while and triggered by sliding some switches around it went back to the 14 ns. Fiddling with the BNC's may have the same effect, i.e. there is a mechanical element to it all. Turns out that running it with the front panel removed I can make it go from 14 to 102 ns by slightly bending the A3 board, certainly while it is cold. After a while this trick doesn't work anymore, my suspicion is whatever crack/gap is causing the trouble has expanded too far to close it tight. After cool-down we're back to square one. I notice there are a few SMD components on that board, right in the middle where it would bend most - basically on the reverse side of the switches. Capacitors and resistors I expect. I wonder if it is worth going over the solder joints of all these carefully. What has stopped me so far are 2 questions: Am I the only one with this observation or has anybody come across this before? Secondly the solder on these SMD's is coated with a black substance. Clearly this could be removed somehow but it is probably there for a reason. Has anybody re-touched joints like these before? On an instrument like this it is very much a case of "proceed with care" and I'd hate to do more damage by rushing in. On a related subject: last year there was a discussion over redesigning the input board(s) for the 5370 / 5345. Did this get off the ground? If my A3 packs up completely... Thanks in advance for any suggestions, Thomas. Date: Wed, 5 Jul 2017 11:00:35 +0100 From: "Thomas Allgeier" To: Subject: Re: [time-nuts] 5370B Question / help needed Message-ID: Content-Type: text/plain; format=flowed; charset="UTF-8"; reply-type=original Thanks all for your help and suggestions - I've been off grid for the last few days. I will look into the dust/contacts issue first, and sweat up on the manual and archive posts in relation to the adjustment procedure. Then I will try to see how far this gets me and report back - watch this space as they say. I may well need the extender cards but since I am based in the UK shipment would have to be considered. Probably worth checking all other options first. Best regards, Thomas. ___ time-nuts mailing 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] 5370B Question / help needed
Thanks all for your help and suggestions - I've been off grid for the last few days. I will look into the dust/contacts issue first, and sweat up on the manual and archive posts in relation to the adjustment procedure. Then I will try to see how far this gets me and report back - watch this space as they say. I may well need the extender cards but since I am based in the UK shipment would have to be considered. Probably worth checking all other options first. Best regards, Thomas. Message: 1 Date: Mon, 3 Jul 2017 08:13:09 -0600 From: Gary Neilson To: time-nuts@febo.com Subject: [time-nuts] Fwd: 5370B Question / help needed Message-ID: <0b65d3e6-c8d0-9eb8-fc70-f36c25ca8...@deepskyridge.com> Content-Type: text/plain; charset=utf-8; format=flowed I have a 5370B from ebay, it was missing a couple of boards and had a bad interpolator card. Also a bad input hybrid on the stop channel. My unit acts similar to yours, TI measurement on the 10mhz signal shows 107 ns. Frequency and Period measurement is spot on. I think it needs an alignment performed. I will get to that soon. Good Luck Gary - K5DSR Forwarded Message Subject: [time-nuts] 5370B Question / help needed Date: Sat, 1 Jul 2017 21:12:27 +0100 From: Thomas Allgeier Reply-To: Discussion of precise time and frequency measurement To: Discussion of precise time and frequency measurement I got hold of a 5370B cheaply but it turns out it may have a fault: Going through the motions of measuring TI with it's own 10MHz ref as input (as described in the manual) I don't get 100 ns, but around 15 ns. So this is with the switch set to START COM. Oddly enough I get the same 15 ns with the switch set to SEP, and going through a 6 ft cable between start and stop. Now I can "tune" the thing to display 100 ns by changing the trigger levels. Start at 0.6 V and stop at -0.1 V will achieve this. Once again this does not change by going from COM to SEP i,e. by adding the 6 ft delay. One other observation, probably related: After powerup it took several vigorous switch activations of the COM/SEP switch before the thing swung into action at all - i.e. the first reaction with COM setting was an Err 02, and with SEP I got the 15 ns as described above. So that switch may be a bit dodgy. Measuring in frequency mode gives the 10 MHz quite accurately, less than 1mHz off with its own ref as stop input. Feeding the 10 MHz in from my GPSDO also ties up OK, it is around 40mHz off with perhaps 5-10mHz jitter. Has anybody come across anything similar? I couldn't find much in that vein in the archive but may have overlooked something. The one thing I was worried about at first was the heat sinks at the rear getting really hot but it seems I'm not the only one with that observation. To some extent it looks like the input levels for triggering are off, but then the fact that the 6 ft cable don't show up as extra delay may mean there is something else wrong. Looks like some "fun with Bill and Dave" lies ahead if somebody can point me in the right direction. Thanks in advance, Thomas. ___ time-nuts mailing 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] 5370B Question / help needed
Plus, when I was aligning mine, I found several errors and omissions in the HP manuals... I can't find my notes now. I do seem to remember some of the dip switch settings were wrong. Also some inconsistencies in the HP- 8082A (?) signal generator setup. Anyway... it's a pain in the ass beastie to align properly. - > They are a highly recommend read if you are getting ready to dig into one of these counters. ___ time-nuts mailing 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] 5370B Question / help needed
Hi If you go back in the archives a few years, there are extensive discussions of the various alignment steps on a 5070A or B. They are a highly recommend read if you are getting ready to dig into one of these counters. Bob > On Jul 3, 2017, at 10:13 AM, Gary Neilson wrote: > > I have a 5370B from ebay, it was missing a couple of boards and had a bad > interpolator card. Also a bad input hybrid on the stop channel. > > My unit acts similar to yours, TI measurement on the 10mhz signal shows 107 > ns. > > Frequency and Period measurement is spot on. > > I think it needs an alignment performed. I will get to that soon. > > Good Luck > > Gary - K5DSR > > > > ---- Forwarded Message ---- > Subject: [time-nuts] 5370B Question / help needed > Date: Sat, 1 Jul 2017 21:12:27 +0100 > From: Thomas Allgeier > Reply-To: Discussion of precise time and frequency measurement > > To: Discussion of precise time and frequency measurement > > > > > I got hold of a 5370B cheaply but it turns out it may have a fault: > > Going through the motions of measuring TI with it's own 10MHz ref as input > (as described in the manual) I don't get 100 ns, but around 15 ns. So this > is with the switch set to START COM. Oddly enough I get the same 15 ns with > the switch set to SEP, and going through a 6 ft cable between start and > stop. > > Now I can "tune" the thing to display 100 ns by changing the trigger > levels. Start at 0.6 V and stop at -0.1 V will achieve this. Once again > this does not change by going from COM to SEP i,e. by adding the 6 ft delay. > > One other observation, probably related: After powerup it took several > vigorous switch activations of the COM/SEP switch before the thing swung > into action at all - i.e. the first reaction with COM setting was an Err > 02, and with SEP I got the 15 ns as described above. So that switch may be > a bit dodgy. > > Measuring in frequency mode gives the 10 MHz quite accurately, less than > 1mHz off with its own ref as stop input. Feeding the 10 MHz in from my > GPSDO also ties up OK, it is around 40mHz off with perhaps 5-10mHz jitter. > > Has anybody come across anything similar? I couldn't find much in that vein > in the archive but may have overlooked something. The one thing I was > worried about at first was the heat sinks at the rear getting really hot > but it seems I'm not the only one with that observation. > > To some extent it looks like the input levels for triggering are off, but > then the fact that the 6 ft cable don't show up as extra delay may mean > there is something else wrong. > > Looks like some "fun with Bill and Dave" lies ahead if somebody can point > me in the right direction. > > Thanks in advance, > Thomas. > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] 5370B Question / help needed
sorry, folks. i meant to sent that directly to mark. On Sun, Jul 2, 2017 at 3:49 PM, Christopher Hoover wrote: > HI Mark, > > >> If you need to troubleshoot the unit, I have a few extender card kits >> left... $30+shipping for the three board set. > > > I'm interested. Waht is the shipping to 94040 residential? > > Thanks, > -ch > 73 de AI6KG > > On Sat, Jul 1, 2017 at 1:23 PM, Mark Sims wrote: > >> This is a very common problem... basically the fan blows directly down >> the chassis onto the front panel area where a large dust bunny builds its >> nest. The switches are gold plated leaf springs that slide on a gold >> plated circuit board. They are open to the environment and collect all >> sort of dust and schmutz. >> >> If you need to troubleshoot the unit, I have a few extender card kits >> left... $30+shipping for the three board set. Two 44-pin boards are used >> to extend a card from the mainframe and there is a 36 (?) pin card that can >> be used with the front panel or oscillator buffer card.. >> >> >> --- >> >> > One other observation, probably related: After powerup it took several >> vigorous switch activations of the COM/SEP switch before the thing swung >> into action at all >> ___ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to https://www.febo.com/cgi-bin/m >> ailman/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] 5370B Question / help needed
HI Mark, > If you need to troubleshoot the unit, I have a few extender card kits > left... $30+shipping for the three board set. I'm interested. Waht is the shipping to 94040 residential? Thanks, -ch 73 de AI6KG On Sat, Jul 1, 2017 at 1:23 PM, Mark Sims wrote: > This is a very common problem... basically the fan blows directly down > the chassis onto the front panel area where a large dust bunny builds its > nest. The switches are gold plated leaf springs that slide on a gold > plated circuit board. They are open to the environment and collect all > sort of dust and schmutz. > > If you need to troubleshoot the unit, I have a few extender card kits > left... $30+shipping for the three board set. Two 44-pin boards are used > to extend a card from the mainframe and there is a 36 (?) pin card that can > be used with the front panel or oscillator buffer card.. > > > --- > > > One other observation, probably related: After powerup it took several > vigorous switch activations of the COM/SEP switch before the thing swung > into action at all > ___ > time-nuts mailing 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] 5370B Question / help needed
Hi, In the manual there is an adjustment procedure. Have you looked at that? DC offsets in trigger points do shift the start and stop triggers. Cheers, Magnus On 07/02/2017 12:16 AM, Thomas Allgeier wrote: Yes, they are both set to "positive". Leaving the start at "pos" and switching the stop to "neg" gives 66 ns. One more observation, which probably does make sense: If I set the ARming to +/-TI and toggle the Period Complement the "sum" is always very close to 100ns: 15 is complemented by -85 and 66 by -34. All this is for Trigger Levels at Preset. When I "tune" the levels to get 100 ns at +TI and then switch to +/-TI I get around 20 ps, and the Complement button has no effect on this. On Sat, Jul 1, 2017 at 9:38 PM, Poul-Henning Kamp wrote: In message , Thomas Allgeier writes: Going through the motions of measuring TI with it's own 10MHz ref as input (as described in the manual) I don't get 100 ns, but around 15 ns. So this is with the switch set to START COM. Oddly enough I get the same 15 ns with the switch set to SEP, and going through a 6 ft cable between start and stop. Have you checked the trigger polarities ? -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] 5370B Question / help needed
This is a very common problem... basically the fan blows directly down the chassis onto the front panel area where a large dust bunny builds its nest. The switches are gold plated leaf springs that slide on a gold plated circuit board. They are open to the environment and collect all sort of dust and schmutz. If you need to troubleshoot the unit, I have a few extender card kits left... $30+shipping for the three board set. Two 44-pin boards are used to extend a card from the mainframe and there is a 36 (?) pin card that can be used with the front panel or oscillator buffer card.. --- > One other observation, probably related: After powerup it took several vigorous switch activations of the COM/SEP switch before the thing swung into action at all ___ time-nuts mailing 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] 5370B Question / help needed
Yes, they are both set to "positive". Leaving the start at "pos" and switching the stop to "neg" gives 66 ns. One more observation, which probably does make sense: If I set the ARming to +/-TI and toggle the Period Complement the "sum" is always very close to 100ns: 15 is complemented by -85 and 66 by -34. All this is for Trigger Levels at Preset. When I "tune" the levels to get 100 ns at +TI and then switch to +/-TI I get around 20 ps, and the Complement button has no effect on this. On Sat, Jul 1, 2017 at 9:38 PM, Poul-Henning Kamp wrote: > > In message gmail.com>, Thomas Allgeier writes: > > >Going through the motions of measuring TI with it's own 10MHz ref as input > >(as described in the manual) I don't get 100 ns, but around 15 ns. So this > >is with the switch set to START COM. Oddly enough I get the same 15 ns > with > >the switch set to SEP, and going through a 6 ft cable between start and > >stop. > > Have you checked the trigger polarities ? > > > -- > Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 > p...@freebsd.org | TCP/IP since RFC 956 > FreeBSD committer | BSD since 4.3-tahoe > Never attribute to malice what can adequately be explained by incompetence. > ___ time-nuts mailing 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] 5370B Question / help needed
In message , Thomas Allgeier writes: >Going through the motions of measuring TI with it's own 10MHz ref as input >(as described in the manual) I don't get 100 ns, but around 15 ns. So this >is with the switch set to START COM. Oddly enough I get the same 15 ns with >the switch set to SEP, and going through a 6 ft cable between start and >stop. Have you checked the trigger polarities ? -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___ time-nuts mailing 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] 5370B Question / help needed
I got hold of a 5370B cheaply but it turns out it may have a fault: Going through the motions of measuring TI with it's own 10MHz ref as input (as described in the manual) I don't get 100 ns, but around 15 ns. So this is with the switch set to START COM. Oddly enough I get the same 15 ns with the switch set to SEP, and going through a 6 ft cable between start and stop. Now I can "tune" the thing to display 100 ns by changing the trigger levels. Start at 0.6 V and stop at -0.1 V will achieve this. Once again this does not change by going from COM to SEP i,e. by adding the 6 ft delay. One other observation, probably related: After powerup it took several vigorous switch activations of the COM/SEP switch before the thing swung into action at all - i.e. the first reaction with COM setting was an Err 02, and with SEP I got the 15 ns as described above. So that switch may be a bit dodgy. Measuring in frequency mode gives the 10 MHz quite accurately, less than 1mHz off with its own ref as stop input. Feeding the 10 MHz in from my GPSDO also ties up OK, it is around 40mHz off with perhaps 5-10mHz jitter. Has anybody come across anything similar? I couldn't find much in that vein in the archive but may have overlooked something. The one thing I was worried about at first was the heat sinks at the rear getting really hot but it seems I'm not the only one with that observation. To some extent it looks like the input levels for triggering are off, but then the fact that the 6 ft cable don't show up as extra delay may mean there is something else wrong. Looks like some "fun with Bill and Dave" lies ahead if somebody can point me in the right direction. Thanks in advance, Thomas. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
