Jim Worse case if you do not find the replacement Digi-key and I would guess mouser caries the filter material for a reasonable price. (At least they did) I needed some to replace a missing piece on a HP 5360 and HP 8505. On Sat, Feb 27, 2010 at 10:44 PM, Jim Cotton <jim.cotton@wmich.edu> wrote: > > I need the red plastic digit cover/window [approximately 1 3/4" x 14 3/4"] > to complete the repair of a HP 5370 counter/timer. I don't care if it says > 5370A or B. I assume that no major change occurred other than the > unit identifier changing. Perhaps someone can correct me if I am wrong in > making this assumption. > > It would be nice to get the bezel clip/strip too, however I suspect that > they tend to disintegrate during removal of the red display cover. > > Does anyone have this available from a parts chassis in their lab? > > I would be happy to pay a reasonable price plus postage. I am located in > Kalamazoo, Michigan, USA. > > Jim Cotton > n8qoh > > _______________________________________________ > 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. >

I have a 5370B that is missing about half of it's red plastic digit cover/window and would like to repair it as well. Do you have a suggestion as to how to start searching Digi-Key and Mouser? Thanks, Joe -----Original Message----- From: time-nuts-bounces@febo.com [mailto:time-nuts-bounces@febo.com] On Behalf Of paul swed Sent: Sunday, February 28, 2010 9:09 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Looking for a 5370 red digit cover/window Jim Worse case if you do not find the replacement Digi-key and I would guess mouser caries the filter material for a reasonable price. (At least they did) I needed some to replace a missing piece on a HP 5360 and HP 8505. On Sat, Feb 27, 2010 at 10:44 PM, Jim Cotton <jim.cotton@wmich.edu> wrote: > > I need the red plastic digit cover/window [approximately 1 3/4" x 14 > 3/4"] to complete the repair of a HP 5370 counter/timer. I don't care > if it says 5370A or B. I assume that no major change occurred other > than the unit identifier changing. Perhaps someone can correct me if > I am wrong in making this assumption. > > It would be nice to get the bezel clip/strip too, however I suspect > that they tend to disintegrate during removal of the red display > cover. > > Does anyone have this available from a parts chassis in their lab? > > I would be happy to pay a reasonable price plus postage. I am located > in Kalamazoo, Michigan, USA. > > Jim Cotton > n8qoh > > _______________________________________________ > 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.

I found them in the led section Try led filter??? On Sun, Feb 28, 2010 at 10:25 AM, J. L. Trantham <jltran@att.net> wrote: > I have a 5370B that is missing about half of it's red plastic digit > cover/window and would like to repair it as well. Do you have a suggestion > as to how to start searching Digi-Key and Mouser? > > Thanks, > > Joe > > -----Original Message----- > From: time-nuts-bounces@febo.com [mailto:time-nuts-bounces@febo.com] On > Behalf Of paul swed > Sent: Sunday, February 28, 2010 9:09 AM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Looking for a 5370 red digit cover/window > > > Jim > Worse case if you do not find the replacement > Digi-key and I would guess mouser caries the filter material for a > reasonable price. (At least they did) I needed some to replace a missing > piece on a HP 5360 and HP 8505. > > > On Sat, Feb 27, 2010 at 10:44 PM, Jim Cotton <jim.cotton@wmich.edu> wrote: > > > > > I need the red plastic digit cover/window [approximately 1 3/4" x 14 > > 3/4"] to complete the repair of a HP 5370 counter/timer. I don't care > > if it says 5370A or B. I assume that no major change occurred other > > than the unit identifier changing. Perhaps someone can correct me if > > I am wrong in making this assumption. > > > > It would be nice to get the bezel clip/strip too, however I suspect > > that they tend to disintegrate during removal of the red display > > cover. > > > > Does anyone have this available from a parts chassis in their lab? > > > > I would be happy to pay a reasonable price plus postage. I am located > > in Kalamazoo, Michigan, USA. > > > > Jim Cotton > > n8qoh > > > > _______________________________________________ > > 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. >

Today I have been trying to drive a 5370B directly from a TADD-2, with little luck (other HP freq counters seem to work OK). I was about to ask about it on this list, but noticed this thread. I guess this could explain why I am getting erroneous, random readings? Dave On Sat, Feb 27, 2010 at 4:01 PM, Bruce Griffiths <bruce.griffiths@xtra.co.nz > wrote: > The attached excerpts from the 5370A and 5370B manuals indicate that for > best performance, that the common practice of driving the 5370A/B 1x inputs > directly from a 5V CMOS logic signal is a bad idea. > > For the 5370A attenuating the 5V CMOS signal to a 1V swing with the > threshold set to 0.5V is close to optimum. > An input signal with limits of 0V and +1.4V with a trigger threshold of > 0.7V is the maximum usable (for high performance). > An input signal with limits of 0V and +0.3V with a trigger threshold of > 0.15V is the minimum usable (for high performance). > > For the 5370A attenuating the 5V CMOS signal to a 2V swing with the > threshold set to 1V is close to optimum. > An input signal with limits of 0V and +3.5V with a trigger threshold of > 0.7V is the maximum usable (for high performance). > An input signal with limits of 0V and +0.3V with a trigger threshold of > 0.15V is the minimum usable (for high performance). > > Bruce > > > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. >

What threshold are you using? If you leave it set to preset/0 volts, you may find that crosstalk between outputs on the TADD-2 cause false triggering. I usually use the divide-by-10 setting with the threshold set to about 0.25V. It also helps to remove the jumpers from any outputs on the TADD-2 you aren't using. -- john, KE5FX > -----Original Message----- > From: time-nuts-bounces@febo.com [mailto:time-nuts-bounces@febo.com]On > Behalf Of Dave hartzell > Sent: Sunday, February 28, 2010 7:28 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Achieving maximum performance when driving > 5370A/Binputs > > > Today I have been trying to drive a 5370B directly from a TADD-2, with > little luck (other HP freq counters seem to work OK). I was about to ask > about it on this list, but noticed this thread. > > I guess this could explain why I am getting erroneous, random readings? > > Dave > > > > On Sat, Feb 27, 2010 at 4:01 PM, Bruce Griffiths > <bruce.griffiths@xtra.co.nz > > wrote: > > > The attached excerpts from the 5370A and 5370B manuals indicate that for > > best performance, that the common practice of driving the > 5370A/B 1x inputs > > directly from a 5V CMOS logic signal is a bad idea. > > > > For the 5370A attenuating the 5V CMOS signal to a 1V swing with the > > threshold set to 0.5V is close to optimum. > > An input signal with limits of 0V and +1.4V with a trigger threshold of > > 0.7V is the maximum usable (for high performance). > > An input signal with limits of 0V and +0.3V with a trigger threshold of > > 0.15V is the minimum usable (for high performance). > > > > For the 5370A attenuating the 5V CMOS signal to a 2V swing with the > > threshold set to 1V is close to optimum. > > An input signal with limits of 0V and +3.5V with a trigger threshold of > > 0.7V is the maximum usable (for high performance). > > An input signal with limits of 0V and +0.3V with a trigger threshold of > > 0.15V is the minimum usable (for high performance). > > > > Bruce > > > > > > _______________________________________________ > > time-nuts mailing list -- time-nuts@febo.com > > To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions there. > > > _______________________________________________ > 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.

The TADD-2 output drivers exhibit significant ringing and crosstalk due to ground and Vcc bounce. To minimise crosstalk dedicate each 74AC04 output device to a single frequency and load. Because of the ringing setting the trigger threshold is more critical than usual. No damage occurs when driving the 5370A/B 1x inputs with 5V logic levels however various protection diodes will turn on and the preamp input stage becomes nonlinear. Bruce Dave hartzell wrote: > Today I have been trying to drive a 5370B directly from a TADD-2, with > little luck (other HP freq counters seem to work OK). I was about to ask > about it on this list, but noticed this thread. > > I guess this could explain why I am getting erroneous, random readings? > > Dave > > > > On Sat, Feb 27, 2010 at 4:01 PM, Bruce Griffiths<bruce.griffiths@xtra.co.nz > >> wrote: >> > >> The attached excerpts from the 5370A and 5370B manuals indicate that for >> best performance, that the common practice of driving the 5370A/B 1x inputs >> directly from a 5V CMOS logic signal is a bad idea. >> >> For the 5370A attenuating the 5V CMOS signal to a 1V swing with the >> threshold set to 0.5V is close to optimum. >> An input signal with limits of 0V and +1.4V with a trigger threshold of >> 0.7V is the maximum usable (for high performance). >> An input signal with limits of 0V and +0.3V with a trigger threshold of >> 0.15V is the minimum usable (for high performance). >> >> For the 5370A attenuating the 5V CMOS signal to a 2V swing with the >> threshold set to 1V is close to optimum. >> An input signal with limits of 0V and +3.5V with a trigger threshold of >> 0.7V is the maximum usable (for high performance). >> An input signal with limits of 0V and +0.3V with a trigger threshold of >> 0.15V is the minimum usable (for high performance). >> >> Bruce >> >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> >> > _______________________________________________ > 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. > >

Thanks for the tips John. Do you use the 50 ohm or 1M ohm settings with the TADD-2? Dave On Sun, Feb 28, 2010 at 7:42 PM, John Miles <jmiles@pop.net> wrote: > What threshold are you using? If you leave it set to preset/0 volts, you > may find that crosstalk between outputs on the TADD-2 cause false > triggering. I usually use the divide-by-10 setting with the threshold set > to about 0.25V. > > It also helps to remove the jumpers from any outputs on the TADD-2 you > aren't using. > > -- john, KE5FX > > > -----Original Message----- > > From: time-nuts-bounces@febo.com [mailto:time-nuts-bounces@febo.com]On > > Behalf Of Dave hartzell > > Sent: Sunday, February 28, 2010 7:28 PM > > To: Discussion of precise time and frequency measurement > > Subject: Re: [time-nuts] Achieving maximum performance when driving > > 5370A/Binputs > > > > > > Today I have been trying to drive a 5370B directly from a TADD-2, with > > little luck (other HP freq counters seem to work OK). I was about to > ask > > about it on this list, but noticed this thread. > > > > I guess this could explain why I am getting erroneous, random readings? > > > > Dave > > > > > > > > On Sat, Feb 27, 2010 at 4:01 PM, Bruce Griffiths > > <bruce.griffiths@xtra.co.nz > > > wrote: > > > > > The attached excerpts from the 5370A and 5370B manuals indicate that > for > > > best performance, that the common practice of driving the > > 5370A/B 1x inputs > > > directly from a 5V CMOS logic signal is a bad idea. > > > > > > For the 5370A attenuating the 5V CMOS signal to a 1V swing with the > > > threshold set to 0.5V is close to optimum. > > > An input signal with limits of 0V and +1.4V with a trigger threshold of > > > 0.7V is the maximum usable (for high performance). > > > An input signal with limits of 0V and +0.3V with a trigger threshold of > > > 0.15V is the minimum usable (for high performance). > > > > > > For the 5370A attenuating the 5V CMOS signal to a 2V swing with the > > > threshold set to 1V is close to optimum. > > > An input signal with limits of 0V and +3.5V with a trigger threshold of > > > 0.7V is the maximum usable (for high performance). > > > An input signal with limits of 0V and +0.3V with a trigger threshold of > > > 0.15V is the minimum usable (for high performance). > > > > > > Bruce > > > > > > > > > _______________________________________________ > > > time-nuts mailing list -- time-nuts@febo.com > > > To unsubscribe, go to > > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > > and follow the instructions there. > > > > > _______________________________________________ > > 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. >

Thanks for the tips Bruce. Is there a "better" version of the 74AC04? It sounds like I should also use an attenuator, perhaps 3 - 10 dB... Dave On Sun, Feb 28, 2010 at 7:43 PM, Bruce Griffiths <bruce.griffiths@xtra.co.nz > wrote: > The TADD-2 output drivers exhibit significant ringing and crosstalk due to > ground and Vcc bounce. > > To minimise crosstalk dedicate each 74AC04 output device to a single > frequency and load. > > Because of the ringing setting the trigger threshold is more critical than > usual. > > No damage occurs when driving the 5370A/B 1x inputs with 5V logic levels > however various protection diodes will turn on and the preamp input stage > becomes nonlinear. > > Bruce > >

If you drive it from 50-ohm coax, you need to use the 50-ohm setting, or the resulting reflections may cause trouble. The 74AC04s in the TADD-2 are happy enough driving 50 ohms, so that's the best way to go. -- john, KE5FX > -----Original Message----- > From: time-nuts-bounces@febo.com [mailto:time-nuts-bounces@febo.com]On > Behalf Of Dave hartzell > Sent: Sunday, February 28, 2010 8:05 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Achieving maximum performance when > driving5370A/Binputs > > > Thanks for the tips John. Do you use the 50 ohm or 1M ohm > settings with the > TADD-2? > > Dave > > > On Sun, Feb 28, 2010 at 7:42 PM, John Miles <jmiles@pop.net> wrote: > > > What threshold are you using? If you leave it set to preset/0 > volts, you > > may find that crosstalk between outputs on the TADD-2 cause false > > triggering. I usually use the divide-by-10 setting with the > threshold set > > to about 0.25V. > > > > It also helps to remove the jumpers from any outputs on the TADD-2 you > > aren't using. > > > > -- john, KE5FX > > > > > -----Original Message----- > > > From: time-nuts-bounces@febo.com [mailto:time-nuts-bounces@febo.com]On > > > Behalf Of Dave hartzell > > > Sent: Sunday, February 28, 2010 7:28 PM > > > To: Discussion of precise time and frequency measurement > > > Subject: Re: [time-nuts] Achieving maximum performance when driving > > > 5370A/Binputs > > > > > > > > > Today I have been trying to drive a 5370B directly from a TADD-2, with > > > little luck (other HP freq counters seem to work OK). I was about to > > ask > > > about it on this list, but noticed this thread. > > > > > > I guess this could explain why I am getting erroneous, random > readings? > > > > > > Dave > > > > > > > > > > > > On Sat, Feb 27, 2010 at 4:01 PM, Bruce Griffiths > > > <bruce.griffiths@xtra.co.nz > > > > wrote: > > > > > > > The attached excerpts from the 5370A and 5370B manuals indicate that > > for > > > > best performance, that the common practice of driving the > > > 5370A/B 1x inputs > > > > directly from a 5V CMOS logic signal is a bad idea. > > > > > > > > For the 5370A attenuating the 5V CMOS signal to a 1V swing with the > > > > threshold set to 0.5V is close to optimum. > > > > An input signal with limits of 0V and +1.4V with a trigger > threshold of > > > > 0.7V is the maximum usable (for high performance). > > > > An input signal with limits of 0V and +0.3V with a trigger > threshold of > > > > 0.15V is the minimum usable (for high performance). > > > > > > > > For the 5370A attenuating the 5V CMOS signal to a 2V swing with the > > > > threshold set to 1V is close to optimum. > > > > An input signal with limits of 0V and +3.5V with a trigger > threshold of > > > > 0.7V is the maximum usable (for high performance). > > > > An input signal with limits of 0V and +0.3V with a trigger > threshold of > > > > 0.15V is the minimum usable (for high performance). > > > > > > > > Bruce > > > > > > > > > > > > _______________________________________________ > > > > time-nuts mailing list -- time-nuts@febo.com > > > > To unsubscribe, go to > > > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > > > and follow the instructions there. > > > > > > > _______________________________________________ > > > 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.

You could substitute a 74AHC04 which has better control of ground and Vcc bounce. At least they are specified. At least a 3dB attenuator with a 5370B. at least 11dB with a 5370A. Or just use the built in 20dB (10x) attenuator. Bruce Dave hartzell wrote: > Thanks for the tips Bruce. > > Is there a "better" version of the 74AC04? It sounds like I should also > use an attenuator, perhaps 3 - 10 dB... > > Dave > > > On Sun, Feb 28, 2010 at 7:43 PM, Bruce Griffiths<bruce.griffiths@xtra.co.nz > >> wrote: >> > >> The TADD-2 output drivers exhibit significant ringing and crosstalk due to >> ground and Vcc bounce. >> >> To minimise crosstalk dedicate each 74AC04 output device to a single >> frequency and load. >> >> Because of the ringing setting the trigger threshold is more critical than >> usual. >> >> No damage occurs when driving the 5370A/B 1x inputs with 5V logic levels >> however various protection diodes will turn on and the preamp input stage >> becomes nonlinear. >> >> Bruce >> >> >> > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > >