[time-nuts] HP5370A vs B version
Once upon a time, I looked into the front ends of the 5370 counters (mostly 5370A) and found that it was practical to build a replacement using modern chips. I then lost interest in the project when I found an Ebay seller with a lot of 10 pieces of the 5370A chip for dirt cheap (sorry, all are now gone). ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] HP5370A vs B version
There was an informative thread back in 2005 on the topic of hp 5370A vs. 5370B: https://www.febo.com/pipermail/time-nuts/2005-April/018053.html It's worth reading the entire thread, or at least, read the reply by JJ (from Agilent T): https://www.febo.com/pipermail/time-nuts/2005-April/018057.html /tvb On 7/19/2019 11:00 AM, Taka Kamiya via time-nuts wrote: What are the differences between HP5370A and 5370B version? I have been told A's input ports are rather delicate and it has been better protected on B version. I found notes on A and B and looked a them side by side but honestly, they are difficult to compare. Anyone on list who had both and can tell from experience? --- (Mr.) Taka Kamiya KB4EMF / ex JF2DKG ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there. ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] HP5370A vs B version
kb...@n1k.org said: [Context is 10811s.] > Because they are an un-sealed unit, power off storage is not kind to them. > Some take a long time to recover. A few never really seem to settle down. What's the mechanism? Lots of stuff ages faster when it is warm/hot. I'd guess humidity. What's the time scale? If 20 years of power off is nasty, is 1 year OK? 1 month? What have we learned about packaging since then? Would a similar design made with modern parts hold up better? -- These are my opinions. I hate spam. ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] HP5370A vs B version
There were field upgrades from HP5370A to B, I believe offered through the HP field services operation. I have an A->B converted unit. I believe it has the original front end, but the “B” firmware. It has been a while since I opened it up. Sent from my iPhone > On Jul 20, 2019, at 10:35, Taka Kamiya via time-nuts > wrote: > > Thank you. > I really do not want to buy from eBay. So far, none showed up with zero > problems. There's always something. My intent is to lock it to house > standard which is a GPSDO. I have lots of 10811 here but I don't know when > they were made. All I know is they are all 10811-6011. You are right - > especially for an instrument like this, standard is extremely important. > > --- > (Mr.) Taka Kamiya > KB4EMF / ex JF2DKG > > >On Saturday, July 20, 2019, 11:02:19 AM EDT, Bob kb8tq > wrote: > > Hi > > If you are buying them on eBay, it is not at all clear which OCXO your A or B > will show up > with. The 10811’s get swapped back and forth with earlier units in a lot of > used gear. One > might *think* it’s a one way exchange, but I’ve seen it go both ways. > > If you lock the counter to an external standard, it really does not matter a > lot which OCXO > is in it. > > Bob > >> On Jul 20, 2019, at 4:21 AM, Frank Stellmach >> wrote: >> >> Hi Mr. Taka Kamiya, >> >> the B version has a 500MHz front end, copied from the HP5345A, with a >> matched pair of amplifier / Schmitt trigger hybrids. >> The A version has separate amplifier and Schmitt trigger ICs. >> >> There were also changes on the trigger circuit. >> >> Then the B version has a simplified µP board, has the OCXO (10811-60111), >> which is a must for absolute T.I. and frequency measurements. >> >> Maybe the firmware was also improved a bit, I think mainly concerning the >> GPIB steering of the trigger circuit. >> >> This T.I. counter is supposed to be superior over others of that era, >> because this special time interpolator was more linear. >> >> I really love mine, so I don't want to sell it. >> >> Frank >> >> >> ___ >> time-nuts mailing list -- time-nuts@lists.febo.com >> To unsubscribe, go to >> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >> and follow the instructions there. > > > ___ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. > > ___ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. > ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] HP5370A vs B version
Am 20.07.19 um 10:21 schrieb Frank Stellmach: the B version has a 500MHz front end, copied from the HP5345A, with a matched pair of amplifier / Schmitt trigger hybrids. The A version has separate amplifier and Schmitt trigger ICs. There were also changes on the trigger circuit. Then the B version has a simplified µP board, has the OCXO (10811-60111), which is a must for absolute T.I. and frequency measurements. My 5370A came with a 10811-60111 time base. It also came with LOTS of intermittent contacts, but it was nearly for free, so I can't complain. I solved the contact problem by buying a SR620 that was still under cal. :-) Gerhard ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] HP5370A vs B version
Hi If you have a pile of 10811’s a fun experiment is to put them on power for a couple months. Log the frequency once a day or so and watch how they “drift in” to whatever the final frequency is. Because they are an un-sealed unit, power off storage is not kind to them. Some take a long time to recover. A few never really seem to settle down. Since the ones that don’t settle are not of a lot of use, they often head off to eBay and get passed from hand to hand over the years. In some cases you *can* find a problem component. There aren’t a lot of people who dig that deep *and* get it right. Bob > On Jul 20, 2019, at 11:35 AM, Taka Kamiya via time-nuts > wrote: > > Thank you. > I really do not want to buy from eBay. So far, none showed up with zero > problems. There's always something. My intent is to lock it to house > standard which is a GPSDO. I have lots of 10811 here but I don't know when > they were made. All I know is they are all 10811-6011. You are right - > especially for an instrument like this, standard is extremely important. > > --- > (Mr.) Taka Kamiya > KB4EMF / ex JF2DKG > > >On Saturday, July 20, 2019, 11:02:19 AM EDT, Bob kb8tq > wrote: > > Hi > > If you are buying them on eBay, it is not at all clear which OCXO your A or B > will show up > with. The 10811’s get swapped back and forth with earlier units in a lot of > used gear. One > might *think* it’s a one way exchange, but I’ve seen it go both ways. > > If you lock the counter to an external standard, it really does not matter a > lot which OCXO > is in it. > > Bob > >> On Jul 20, 2019, at 4:21 AM, Frank Stellmach >> wrote: >> >> Hi Mr. Taka Kamiya, >> >> the B version has a 500MHz front end, copied from the HP5345A, with a >> matched pair of amplifier / Schmitt trigger hybrids. >> The A version has separate amplifier and Schmitt trigger ICs. >> >> There were also changes on the trigger circuit. >> >> Then the B version has a simplified µP board, has the OCXO (10811-60111), >> which is a must for absolute T.I. and frequency measurements. >> >> Maybe the firmware was also improved a bit, I think mainly concerning the >> GPIB steering of the trigger circuit. >> >> This T.I. counter is supposed to be superior over others of that era, >> because this special time interpolator was more linear. >> >> I really love mine, so I don't want to sell it. >> >> Frank >> >> >> ___ >> time-nuts mailing list -- time-nuts@lists.febo.com >> To unsubscribe, go to >> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >> and follow the instructions there. > > > ___ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. > > ___ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] HP5370A vs B version
Thank you. I really do not want to buy from eBay. So far, none showed up with zero problems. There's always something. My intent is to lock it to house standard which is a GPSDO. I have lots of 10811 here but I don't know when they were made. All I know is they are all 10811-6011. You are right - especially for an instrument like this, standard is extremely important. --- (Mr.) Taka Kamiya KB4EMF / ex JF2DKG On Saturday, July 20, 2019, 11:02:19 AM EDT, Bob kb8tq wrote: Hi If you are buying them on eBay, it is not at all clear which OCXO your A or B will show up with. The 10811’s get swapped back and forth with earlier units in a lot of used gear. One might *think* it’s a one way exchange, but I’ve seen it go both ways. If you lock the counter to an external standard, it really does not matter a lot which OCXO is in it. Bob > On Jul 20, 2019, at 4:21 AM, Frank Stellmach > wrote: > > Hi Mr. Taka Kamiya, > > the B version has a 500MHz front end, copied from the HP5345A, with a matched > pair of amplifier / Schmitt trigger hybrids. > The A version has separate amplifier and Schmitt trigger ICs. > > There were also changes on the trigger circuit. > > Then the B version has a simplified µP board, has the OCXO (10811-60111), > which is a must for absolute T.I. and frequency measurements. > > Maybe the firmware was also improved a bit, I think mainly concerning the > GPIB steering of the trigger circuit. > > This T.I. counter is supposed to be superior over others of that era, because > this special time interpolator was more linear. > > I really love mine, so I don't want to sell it. > > Frank > > > ___ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there. ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] HP5370A vs B version
Hi If you are buying them on eBay, it is not at all clear which OCXO your A or B will show up with. The 10811’s get swapped back and forth with earlier units in a lot of used gear. One might *think* it’s a one way exchange, but I’ve seen it go both ways. If you lock the counter to an external standard, it really does not matter a lot which OCXO is in it. Bob > On Jul 20, 2019, at 4:21 AM, Frank Stellmach > wrote: > > Hi Mr. Taka Kamiya, > > the B version has a 500MHz front end, copied from the HP5345A, with a matched > pair of amplifier / Schmitt trigger hybrids. > The A version has separate amplifier and Schmitt trigger ICs. > > There were also changes on the trigger circuit. > > Then the B version has a simplified µP board, has the OCXO (10811-60111), > which is a must for absolute T.I. and frequency measurements. > > Maybe the firmware was also improved a bit, I think mainly concerning the > GPIB steering of the trigger circuit. > > This T.I. counter is supposed to be superior over others of that era, because > this special time interpolator was more linear. > > I really love mine, so I don't want to sell it. > > Frank > > > ___ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
[time-nuts] HP5370A vs B version
Hi Mr. Taka Kamiya, the B version has a 500MHz front end, copied from the HP5345A, with a matched pair of amplifier / Schmitt trigger hybrids. The A version has separate amplifier and Schmitt trigger ICs. There were also changes on the trigger circuit. Then the B version has a simplified µP board, has the OCXO (10811-60111), which is a must for absolute T.I. and frequency measurements. Maybe the firmware was also improved a bit, I think mainly concerning the GPIB steering of the trigger circuit. This T.I. counter is supposed to be superior over others of that era, because this special time interpolator was more linear. I really love mine, so I don't want to sell it. Frank ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
[time-nuts] HP5370A vs B version
The "B" version uses custom hybrid modules for the inputs... and the CH1 and CH2 hybrids are not the same... so you can't swap a CH1 hybrid with a CH2 hybrid. I think the A and B model counters are fairly equivalent in their sensitivity to input damage. It seems to be a lot harder to find replacement parts for the "B". ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] HP5370A vs B version
Hi They both run hot and have “interesting” calibration procedures. Count on spending some time running through this and that to get the best performance out of them. The B does seem to run a bit better, but both meet the same basic specs. The SR610 is a very similar device (with some similar calibration procedures). I would go for one of them rather than the 5370. The 610 seems to be just a little bit easier to keep running. If cost is no object ( … as if …) there are indeed a number of devices out there that now do a much better job than the 610 or the 5370. Finding (say) a TImePod on the used market seems to be a bit rare …. Bob > On Jul 19, 2019, at 2:00 PM, Taka Kamiya via time-nuts > wrote: > > What are the differences between HP5370A and 5370B version? > I have been told A's input ports are rather delicate and it has been better > protected on B version. I found notes on A and B and looked a them side by > side but honestly, they are difficult to compare. Anyone on list who had > both and can tell from experience? > > --- > (Mr.) Taka Kamiya > KB4EMF / ex JF2DKG > ___ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
[time-nuts] HP5370A vs B version
What are the differences between HP5370A and 5370B version? I have been told A's input ports are rather delicate and it has been better protected on B version. I found notes on A and B and looked a them side by side but honestly, they are difficult to compare. Anyone on list who had both and can tell from experience? --- (Mr.) Taka Kamiya KB4EMF / ex JF2DKG ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
