Re: [time-nuts] EIP545A 18GHz counter query
> Me too. > I have two 545A's, one of which works and the other of which has issues with > Band 3, failing to read in a very interesting pattern suggesting a YIG > filter issue, probably the control circuit. > Just no time to chase it right now. > Please post the resolution. > Thanks. > Joe 17/12/2012 12:31 Thanks to all who have assisted here, and in particular Paul Swed, who via Skype helped me do the final de bugging, with expert knowldege and good humour.. As requested the final resolution. The biassing of Q12 was critical and R54 had changed in value by some 25%. It should have been 11k, but I only had a 10k, which got it counting correctly on Band 2 again. I sourced the correct 11k resistors at 1% and also changed R55 and the 10 ohm in the 12 volt feed. All seems well now, although I have no means to check Band 3 above 1024 MHz, the limit of my signal generator. Any ideas on getting a high frequency into the thing? Hope this may help someone, the switching arrangement is a bit odd at Q12, I think I know why, but won't cloud the water with misinformation. Thanks everyone, have a good Christmas and a happy New Year. -- Best Regards, Chris Wilson. ___ 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] EIP545A 18GHz counter query
Yes. There is a Yahoo Group spwecifically about EIP products. -John > > >> I have an EIP counter with a problem, stashed, that I need to look at >> eventually. So have been following the thread a bit. > >> If you guys get somewhere conclusive (or not), might be nice to post a >> summary of all important details, techniques, or circuit notes beyond >> the manual, found, to this thread for closing to posterity searchers. >> (And me.) > >> And, in the mean time, good luck, bon debugging. > >> -Rex > > > > > 10/12/2012 13:40 > > Will do Rex, but I was worried this thread may not have been strictly on > topic for this reflector. Comments? > > -- >Best Regards, >Chris Wilson. > > > ___ > 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] EIP545A 18GHz counter query
I'm already over there. The thread just migrated back here. Joe -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Steve Sent: Monday, December 10, 2012 8:43 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] EIP545A 18GHz counter query Or join and post to the EIP_Microwave Yahoo group - lots of good info showing up there! Steve WB0DBS On Dec 10, 2012, at 8:00 AM, "J. L. Trantham" wrote: > Me too. > > I have two 545A's, one of which works and the other of which has > issues with Band 3, failing to read in a very interesting pattern > suggesting a YIG filter issue, probably the control circuit. > > Just no time to chase it right now. > > Please post the resolution. > > Thanks. > > Joe > > > -Original Message- > From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] > On Behalf Of Rex > Sent: Monday, December 10, 2012 6:50 AM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] EIP545A 18GHz counter query > > > I have an EIP counter with a problem, stashed, that I need to look at > eventually. So have been following the thread a bit. > > If you guys get somewhere conclusive (or not), might be nice to post a > summary of all important details, techniques, or circuit notes beyond > the manual, found, to this thread for closing to posterity searchers. > (And me.) > > And, in the mean time, good luck, bon debugging. > > -Rex > > > On 12/9/2012 8:41 AM, paul swed wrote: >> Chris >> TP4 is not all that helpful its a control signal. >> So let me back up for a minute. What are we troubleshooting? I was >> thinking band 2 was semi working and you still had a totally dead band >> 3. My comments have been around trying to see what was going on with >> 3. Other comment. >> I think we should take this offline. Most likely driving time-nuts nuts. > :-) >> Do you use skype? >> Regards >> Paul >> > > > ___ > 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.
Re: [time-nuts] EIP545A 18GHz counter query
Or join and post to the EIP_Microwave Yahoo group - lots of good info showing up there! Steve WB0DBS On Dec 10, 2012, at 8:00 AM, "J. L. Trantham" wrote: > Me too. > > I have two 545A's, one of which works and the other of which has issues with > Band 3, failing to read in a very interesting pattern suggesting a YIG > filter issue, probably the control circuit. > > Just no time to chase it right now. > > Please post the resolution. > > Thanks. > > Joe > > > -Original Message- > From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On > Behalf Of Rex > Sent: Monday, December 10, 2012 6:50 AM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] EIP545A 18GHz counter query > > > I have an EIP counter with a problem, stashed, that I need to look at > eventually. So have been following the thread a bit. > > If you guys get somewhere conclusive (or not), might be nice to post a > summary of all important details, techniques, or circuit notes beyond > the manual, found, to this thread for closing to posterity searchers. > (And me.) > > And, in the mean time, good luck, bon debugging. > > -Rex > > > On 12/9/2012 8:41 AM, paul swed wrote: >> Chris >> TP4 is not all that helpful its a control signal. >> So let me back up for a minute. What are we troubleshooting? I was >> thinking band 2 was semi working and you still had a totally dead band >> 3. My comments have been around trying to see what was going on with >> 3. Other comment. >> I think we should take this offline. Most likely driving time-nuts nuts. > :-) >> Do you use skype? >> Regards >> Paul >> > > > ___ > 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] EIP545A 18GHz counter query
Chris and I took this offline so as not to bother the time-nuts thread. Hopefully we can work it through. Chris is lucky as he only has a band 2 problem. Band 3 in nastier o deal with. Chris since several have expressed interest perhaps we just add them to your new thread. We can still skype for the real time work. Joe to your 545. Lots of possibilities. There is the yig tuning circuit driven by a dac driven by a 6.2V zener reference. I have run into bad zeners more then I care to count. Plus the other part of the equation is the locked comb source. So as I say band 3 is nasty lots can go wrong besides someone simply frying the front end. Regards Paul On Mon, Dec 10, 2012 at 9:00 AM, J. L. Trantham wrote: > Me too. > > I have two 545A's, one of which works and the other of which has issues > with > Band 3, failing to read in a very interesting pattern suggesting a YIG > filter issue, probably the control circuit. > > Just no time to chase it right now. > > Please post the resolution. > > Thanks. > > Joe > > > -Original Message- > From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On > Behalf Of Rex > Sent: Monday, December 10, 2012 6:50 AM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] EIP545A 18GHz counter query > > > I have an EIP counter with a problem, stashed, that I need to look at > eventually. So have been following the thread a bit. > > If you guys get somewhere conclusive (or not), might be nice to post a > summary of all important details, techniques, or circuit notes beyond > the manual, found, to this thread for closing to posterity searchers. > (And me.) > > And, in the mean time, good luck, bon debugging. > > -Rex > > > On 12/9/2012 8:41 AM, paul swed wrote: > > Chris > > TP4 is not all that helpful its a control signal. > > So let me back up for a minute. What are we troubleshooting? I was > > thinking band 2 was semi working and you still had a totally dead band > > 3. My comments have been around trying to see what was going on with > > 3. Other comment. > > I think we should take this offline. Most likely driving time-nuts nuts. > :-) > > Do you use skype? > > Regards > > Paul > > > > > ___ > 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] EIP545A 18GHz counter query
Me too. I have two 545A's, one of which works and the other of which has issues with Band 3, failing to read in a very interesting pattern suggesting a YIG filter issue, probably the control circuit. Just no time to chase it right now. Please post the resolution. Thanks. Joe -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Rex Sent: Monday, December 10, 2012 6:50 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] EIP545A 18GHz counter query I have an EIP counter with a problem, stashed, that I need to look at eventually. So have been following the thread a bit. If you guys get somewhere conclusive (or not), might be nice to post a summary of all important details, techniques, or circuit notes beyond the manual, found, to this thread for closing to posterity searchers. (And me.) And, in the mean time, good luck, bon debugging. -Rex On 12/9/2012 8:41 AM, paul swed wrote: > Chris > TP4 is not all that helpful its a control signal. > So let me back up for a minute. What are we troubleshooting? I was > thinking band 2 was semi working and you still had a totally dead band > 3. My comments have been around trying to see what was going on with > 3. Other comment. > I think we should take this offline. Most likely driving time-nuts nuts. :-) > Do you use skype? > Regards > Paul > ___ 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] EIP545A 18GHz counter query
> I have an EIP counter with a problem, stashed, that I need to look at > eventually. So have been following the thread a bit. > If you guys get somewhere conclusive (or not), might be nice to post a > summary of all important details, techniques, or circuit notes beyond > the manual, found, to this thread for closing to posterity searchers. > (And me.) > And, in the mean time, good luck, bon debugging. > -Rex 10/12/2012 13:40 Will do Rex, but I was worried this thread may not have been strictly on topic for this reflector. Comments? -- Best Regards, Chris Wilson. ___ 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] EIP545A 18GHz counter query
I have an EIP counter with a problem, stashed, that I need to look at eventually. So have been following the thread a bit. If you guys get somewhere conclusive (or not), might be nice to post a summary of all important details, techniques, or circuit notes beyond the manual, found, to this thread for closing to posterity searchers. (And me.) And, in the mean time, good luck, bon debugging. -Rex On 12/9/2012 8:41 AM, paul swed wrote: Chris TP4 is not all that helpful its a control signal. So let me back up for a minute. What are we troubleshooting? I was thinking band 2 was semi working and you still had a totally dead band 3. My comments have been around trying to see what was going on with 3. Other comment. I think we should take this offline. Most likely driving time-nuts nuts. :-) Do you use skype? Regards Paul ___ 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] EIP545A 18GHz counter query
> Chris > TP4 is not all that helpful its a control signal. > So let me back up for a minute. What are we troubleshooting? > I was thinking band 2 was semi working and you still had a totally dead > band 3. > My comments have been around trying to see what was going on with 3. > Other comment. > I think we should take this offline. Most likely driving time-nuts nuts. :-) > Do you use skype? > Regards > Paul > On Sun, Dec 9, 2012 at 11:29 AM, paul swed wrote: >> Didier is 100% correct though I use a 10 db pad for exactly the same >> purpose. You have to be careful. In your case there is a +28 db power amp >> that feeds the yig mixer in the 545. That would destroy the spectrum >> analyzer frontend. In fact if measuring that component you would want 30 db >> of loss using a 2 watt pad. Most spectrum analyzers run in the 0 to +5 or >> so db range. >> >> All of that said I actually have to look at your other comments to make >> some sense of what you are seeing. >> Regards >> Paul >> WB8TSL >> >> >> On Sun, Dec 9, 2012 at 7:22 AM, wrote: >> >>> Good practice with a spectrum analyzer is to put a 20 dB pad at the input >>> all the time unless you are sure you don't need it for a particular >>> measurement. >>> >>> It has saved my bacon many times. >>> >>> It also protects the input connector from excessive wear. >>> >>> Didier KO4BB >>> >>> >>> Sent from my Droid Razr 4G LTE wireless tracker. >>> >>> >>> >>> -Original Message- >>> From: Chris Wilson >>> To: Chris Wilson , Discussion of precise time and >>> frequency measurement >>> Sent: Sun, 09 Dec 2012 5:54 AM >>> Subject: Re: [time-nuts] EIP545A 18GHz counter query >>> >>> >>> >>> > Did do some more reading and I think what I suggest is the right >>> approach. >>> > Band 2 and 3 use the same VCO. So if band 2 is generally working >>> > then its possibly the rf multiplier yig filter mixer diodes etc. But >>> > if the RF detectors show RF then its going to be a much more >>> interesting issue. >>> > I do not know what sort of test equipment you might have. I have >>> > spectrum analyzers and such. And do agree without extenders that I >>> don't have its a royal pain. >>> > Regards >>> > Paul. >>> >>> >>> 09/12/2012 11:45 >>> >>> Thanks very much for your input with this, much appreciated. I do have >>> a spectrum analyser, but it's a bit like having a set of surgeons >>> implements. Interesting to have, but needing the requisite skill to >>> use safely :) I can do only the most basic stuff, to be frank I am >>> very wary of blowing the input stage up by doing something daft! >>> >>> I think I follow your train of thought here Paul. But, before seeing >>> your post I did some tests at TP4, to see if the unit was constantly >>> scanning for a signal when on Band 2. here is what I found and saw: >>> >>> I have now refitted the new Q12, and removed the test 1k resistor. >>> >>> OK, the trace from TP4 does different things depending what band it is >>> on. Bands 1 and 3 it just sits there, #1. On Band 2 it gives what appears >>> to be two traces, #2. Changing the timebase gives the other trace I show >>> linked, #3. On bands 1 and 3 only a single trace appears. So Band 2 is >>> doing something different at TP4, with no input signal. Warm Q12 with >>> an input signal to Band 2 and the two traces change to a single trace, >>> #4. >>> >>> Once it cools again the two traces return. >>> >>> Traces: >>> >>> #1 http://www.gatesgarth.com/scope/TP4-band1.jpg >>> >>> #2 http://www.gatesgarth.com/scope/TP4-band2.jpg >>> >>> #3 http://www.gatesgarth.com/scope/TP4-...t-timebase.jpg >>> >>> #4 http://www.gatesgarth.com/scope/TP4-...put-signal.jpg >>> >>> I would need explicit instruction to poke about using the SA. It's an >>> HP 8568B. Thanks again Paul :) >>> >>> >>> >>> -- >>>Best Regards, >>>Chris Wilson. >>> >>> >>> ___ >>> 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. 09/12/2012 19:53 Will send direct e-mail thanks for everyone's he;p and patience. -- Best Regards, Chris Wilson. ___ 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] EIP545A 18GHz counter query
Chris TP4 is not all that helpful its a control signal. So let me back up for a minute. What are we troubleshooting? I was thinking band 2 was semi working and you still had a totally dead band 3. My comments have been around trying to see what was going on with 3. Other comment. I think we should take this offline. Most likely driving time-nuts nuts. :-) Do you use skype? Regards Paul On Sun, Dec 9, 2012 at 11:29 AM, paul swed wrote: > Didier is 100% correct though I use a 10 db pad for exactly the same > purpose. You have to be careful. In your case there is a +28 db power amp > that feeds the yig mixer in the 545. That would destroy the spectrum > analyzer frontend. In fact if measuring that component you would want 30 db > of loss using a 2 watt pad. Most spectrum analyzers run in the 0 to +5 or > so db range. > > All of that said I actually have to look at your other comments to make > some sense of what you are seeing. > Regards > Paul > WB8TSL > > > On Sun, Dec 9, 2012 at 7:22 AM, wrote: > >> Good practice with a spectrum analyzer is to put a 20 dB pad at the input >> all the time unless you are sure you don't need it for a particular >> measurement. >> >> It has saved my bacon many times. >> >> It also protects the input connector from excessive wear. >> >> Didier KO4BB >> >> >> Sent from my Droid Razr 4G LTE wireless tracker. >> >> >> >> -Original Message- >> From: Chris Wilson >> To: Chris Wilson , Discussion of precise time and >> frequency measurement >> Sent: Sun, 09 Dec 2012 5:54 AM >> Subject: Re: [time-nuts] EIP545A 18GHz counter query >> >> >> >> > Did do some more reading and I think what I suggest is the right >> approach. >> > Band 2 and 3 use the same VCO. So if band 2 is generally working >> > then its possibly the rf multiplier yig filter mixer diodes etc. But >> > if the RF detectors show RF then its going to be a much more >> interesting issue. >> > I do not know what sort of test equipment you might have. I have >> > spectrum analyzers and such. And do agree without extenders that I >> don't have its a royal pain. >> > Regards >> > Paul. >> >> >> 09/12/2012 11:45 >> >> Thanks very much for your input with this, much appreciated. I do have >> a spectrum analyser, but it's a bit like having a set of surgeons >> implements. Interesting to have, but needing the requisite skill to >> use safely :) I can do only the most basic stuff, to be frank I am >> very wary of blowing the input stage up by doing something daft! >> >> I think I follow your train of thought here Paul. But, before seeing >> your post I did some tests at TP4, to see if the unit was constantly >> scanning for a signal when on Band 2. here is what I found and saw: >> >> I have now refitted the new Q12, and removed the test 1k resistor. >> >> OK, the trace from TP4 does different things depending what band it is >> on. Bands 1 and 3 it just sits there, #1. On Band 2 it gives what appears >> to be two traces, #2. Changing the timebase gives the other trace I show >> linked, #3. On bands 1 and 3 only a single trace appears. So Band 2 is >> doing something different at TP4, with no input signal. Warm Q12 with >> an input signal to Band 2 and the two traces change to a single trace, >> #4. >> >> Once it cools again the two traces return. >> >> Traces: >> >> #1 http://www.gatesgarth.com/scope/TP4-band1.jpg >> >> #2 http://www.gatesgarth.com/scope/TP4-band2.jpg >> >> #3 http://www.gatesgarth.com/scope/TP4-...t-timebase.jpg >> >> #4 http://www.gatesgarth.com/scope/TP4-...put-signal.jpg >> >> I would need explicit instruction to poke about using the SA. It's an >> HP 8568B. Thanks again Paul :) >> >> >> >> -- >>Best Regards, >>Chris Wilson. >> >> >> ___ >> 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] EIP545A 18GHz counter query
Didier is 100% correct though I use a 10 db pad for exactly the same purpose. You have to be careful. In your case there is a +28 db power amp that feeds the yig mixer in the 545. That would destroy the spectrum analyzer frontend. In fact if measuring that component you would want 30 db of loss using a 2 watt pad. Most spectrum analyzers run in the 0 to +5 or so db range. All of that said I actually have to look at your other comments to make some sense of what you are seeing. Regards Paul WB8TSL On Sun, Dec 9, 2012 at 7:22 AM, wrote: > Good practice with a spectrum analyzer is to put a 20 dB pad at the input > all the time unless you are sure you don't need it for a particular > measurement. > > It has saved my bacon many times. > > It also protects the input connector from excessive wear. > > Didier KO4BB > > > Sent from my Droid Razr 4G LTE wireless tracker. > > > > -Original Message- > From: Chris Wilson > To: Chris Wilson , Discussion of precise time and > frequency measurement > Sent: Sun, 09 Dec 2012 5:54 AM > Subject: Re: [time-nuts] EIP545A 18GHz counter query > > > > > Did do some more reading and I think what I suggest is the right > approach. > > Band 2 and 3 use the same VCO. So if band 2 is generally working > > then its possibly the rf multiplier yig filter mixer diodes etc. But > > if the RF detectors show RF then its going to be a much more interesting > issue. > > I do not know what sort of test equipment you might have. I have > > spectrum analyzers and such. And do agree without extenders that I don't > have its a royal pain. > > Regards > > Paul. > > > 09/12/2012 11:45 > > Thanks very much for your input with this, much appreciated. I do have > a spectrum analyser, but it's a bit like having a set of surgeons > implements. Interesting to have, but needing the requisite skill to > use safely :) I can do only the most basic stuff, to be frank I am > very wary of blowing the input stage up by doing something daft! > > I think I follow your train of thought here Paul. But, before seeing > your post I did some tests at TP4, to see if the unit was constantly > scanning for a signal when on Band 2. here is what I found and saw: > > I have now refitted the new Q12, and removed the test 1k resistor. > > OK, the trace from TP4 does different things depending what band it is > on. Bands 1 and 3 it just sits there, #1. On Band 2 it gives what appears > to be two traces, #2. Changing the timebase gives the other trace I show > linked, #3. On bands 1 and 3 only a single trace appears. So Band 2 is > doing something different at TP4, with no input signal. Warm Q12 with > an input signal to Band 2 and the two traces change to a single trace, > #4. > > Once it cools again the two traces return. > > Traces: > > #1 http://www.gatesgarth.com/scope/TP4-band1.jpg > > #2 http://www.gatesgarth.com/scope/TP4-band2.jpg > > #3 http://www.gatesgarth.com/scope/TP4-...t-timebase.jpg > > #4 http://www.gatesgarth.com/scope/TP4-...put-signal.jpg > > I would need explicit instruction to poke about using the SA. It's an > HP 8568B. Thanks again Paul :) > > > > -- >Best Regards, >Chris Wilson. > > > ___ > 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] EIP545A 18GHz counter query
Good practice with a spectrum analyzer is to put a 20 dB pad at the input all the time unless you are sure you don't need it for a particular measurement. It has saved my bacon many times. It also protects the input connector from excessive wear. Didier KO4BB Sent from my Droid Razr 4G LTE wireless tracker. -Original Message- From: Chris Wilson To: Chris Wilson , Discussion of precise time and frequency measurement Sent: Sun, 09 Dec 2012 5:54 AM Subject: Re: [time-nuts] EIP545A 18GHz counter query > Did do some more reading and I think what I suggest is the right approach. > Band 2 and 3 use the same VCO. So if band 2 is generally working > then its possibly the rf multiplier yig filter mixer diodes etc. But > if the RF detectors show RF then its going to be a much more interesting > issue. > I do not know what sort of test equipment you might have. I have > spectrum analyzers and such. And do agree without extenders that I don't have > its a royal pain. > Regards > Paul. 09/12/2012 11:45 Thanks very much for your input with this, much appreciated. I do have a spectrum analyser, but it's a bit like having a set of surgeons implements. Interesting to have, but needing the requisite skill to use safely :) I can do only the most basic stuff, to be frank I am very wary of blowing the input stage up by doing something daft! I think I follow your train of thought here Paul. But, before seeing your post I did some tests at TP4, to see if the unit was constantly scanning for a signal when on Band 2. here is what I found and saw: I have now refitted the new Q12, and removed the test 1k resistor. OK, the trace from TP4 does different things depending what band it is on. Bands 1 and 3 it just sits there, #1. On Band 2 it gives what appears to be two traces, #2. Changing the timebase gives the other trace I show linked, #3. On bands 1 and 3 only a single trace appears. So Band 2 is doing something different at TP4, with no input signal. Warm Q12 with an input signal to Band 2 and the two traces change to a single trace, #4. Once it cools again the two traces return. Traces: #1 http://www.gatesgarth.com/scope/TP4-band1.jpg #2 http://www.gatesgarth.com/scope/TP4-band2.jpg #3 http://www.gatesgarth.com/scope/TP4-...t-timebase.jpg #4 http://www.gatesgarth.com/scope/TP4-...put-signal.jpg I would need explicit instruction to poke about using the SA. It's an HP 8568B. Thanks again Paul :) -- Best Regards, Chris Wilson. ___ 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] EIP545A 18GHz counter query
> Did do some more reading and I think what I suggest is the right approach. > Band 2 and 3 use the same VCO. So if band 2 is generally working > then its possibly the rf multiplier yig filter mixer diodes etc. But > if the RF detectors show RF then its going to be a much more interesting > issue. > I do not know what sort of test equipment you might have. I have > spectrum analyzers and such. And do agree without extenders that I don't have > its a royal pain. > Regards > Paul. 09/12/2012 11:45 Thanks very much for your input with this, much appreciated. I do have a spectrum analyser, but it's a bit like having a set of surgeons implements. Interesting to have, but needing the requisite skill to use safely :) I can do only the most basic stuff, to be frank I am very wary of blowing the input stage up by doing something daft! I think I follow your train of thought here Paul. But, before seeing your post I did some tests at TP4, to see if the unit was constantly scanning for a signal when on Band 2. here is what I found and saw: I have now refitted the new Q12, and removed the test 1k resistor. OK, the trace from TP4 does different things depending what band it is on. Bands 1 and 3 it just sits there, #1. On Band 2 it gives what appears to be two traces, #2. Changing the timebase gives the other trace I show linked, #3. On bands 1 and 3 only a single trace appears. So Band 2 is doing something different at TP4, with no input signal. Warm Q12 with an input signal to Band 2 and the two traces change to a single trace, #4. Once it cools again the two traces return. Traces: #1 http://www.gatesgarth.com/scope/TP4-band1.jpg #2 http://www.gatesgarth.com/scope/TP4-band2.jpg #3 http://www.gatesgarth.com/scope/TP4-...t-timebase.jpg #4 http://www.gatesgarth.com/scope/TP4-...put-signal.jpg I would need explicit instruction to poke about using the SA. It's an HP 8568B. Thanks again Paul :) -- Best Regards, Chris Wilson. ___ 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] EIP545A 18GHz counter query
Did do some more reading and I think what I suggest is the right approach. Band 2 and 3 use the same VCO. So if band 2 is generally working then its possibly the rf multiplier yig filter mixer diodes etc. But if the RF detectors show RF then its going to be a much more interesting issue. I do not know what sort of test equipment you might have. I have spectrum analyzers and such. And do agree without extenders that I don't have its a royal pain. Regards Paul. On Fri, Dec 7, 2012 at 9:52 AM, paul swed wrote: > Chris > So you also must run the gatesgarth website. I was thinking there might be > other good tidbits. The EIP manual was nice. Good job on the control signal. > I had a chance to reread the theory of operation yesterday (Well parts) > and if band 2 is now working by cheating at least, then it would be > interesting to look at band 3 and see whats going on. > There seems to be 3 variables that control operation. 1 you have > experimented with the next is the band 2 or band 3 selection and then the > 3rd is how the system searches for a signal in either band. > This seems to be a diode detector in the front end and a diode detector in > the IF. When a signal is detected at the front and the signal in the IF is > larger the system says I have a signal in the correct down conversion band. > The operational logic diagrams are far more clear. > So the trick in band 3 would be to look at the IF rf diode and see if it > ever has a voltage. That would give a hint as to what direction to look in. > Sure you could look at the LO with a spectrum analyzer and see if it was > correct also. You just might not have one. :-) > Regards > Paul > WB8TSL > > > On Fri, Dec 7, 2012 at 5:22 AM, Chris Wilson wrote: > >> >> >> >> >> >> __ >> >> > This is where I am now, I hope the above makes some sense if >> > viewed with the service manual and the schematics. Thanks. >> >> >> >> >> 07/12/2012 10:17 >> >> Latest update: >> >> Removed Q12 from board A109 and put a 1k resistor across vacant >> emitter and collector board holes, thus putting 12 volts into the >> mixer to switch it externally. Counter now works perfectly on Band 2 >> and I followed the signal path from R2 / R3 junction (wrong impedance, >> but a reference nonetheless) through to the anode of CR3. >> >> Hopefully self explanatory with regard to file names, scope patterns >> are at http://www.gatesgarth.com/scope/scope.zip >> >> Pretty stuck as to where to go next now. >> >> >> >> -- >>Best Regards, >>Chris Wilson. >> >> >> ___ >> 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] EIP545A 18GHz counter query
Chris So you also must run the gatesgarth website. I was thinking there might be other good tidbits. The EIP manual was nice. Good job on the control signal. I had a chance to reread the theory of operation yesterday (Well parts) and if band 2 is now working by cheating at least, then it would be interesting to look at band 3 and see whats going on. There seems to be 3 variables that control operation. 1 you have experimented with the next is the band 2 or band 3 selection and then the 3rd is how the system searches for a signal in either band. This seems to be a diode detector in the front end and a diode detector in the IF. When a signal is detected at the front and the signal in the IF is larger the system says I have a signal in the correct down conversion band. The operational logic diagrams are far more clear. So the trick in band 3 would be to look at the IF rf diode and see if it ever has a voltage. That would give a hint as to what direction to look in. Sure you could look at the LO with a spectrum analyzer and see if it was correct also. You just might not have one. :-) Regards Paul WB8TSL On Fri, Dec 7, 2012 at 5:22 AM, Chris Wilson wrote: > > > > > > __ > > > This is where I am now, I hope the above makes some sense if > > viewed with the service manual and the schematics. Thanks. > > > > > 07/12/2012 10:17 > > Latest update: > > Removed Q12 from board A109 and put a 1k resistor across vacant > emitter and collector board holes, thus putting 12 volts into the > mixer to switch it externally. Counter now works perfectly on Band 2 > and I followed the signal path from R2 / R3 junction (wrong impedance, > but a reference nonetheless) through to the anode of CR3. > > Hopefully self explanatory with regard to file names, scope patterns > are at http://www.gatesgarth.com/scope/scope.zip > > Pretty stuck as to where to go next now. > > > > -- >Best Regards, >Chris Wilson. > > > ___ > 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] EIP545A 18GHz counter query
__ > This is where I am now, I hope the above makes some sense if > viewed with the service manual and the schematics. Thanks. 07/12/2012 10:17 Latest update: Removed Q12 from board A109 and put a 1k resistor across vacant emitter and collector board holes, thus putting 12 volts into the mixer to switch it externally. Counter now works perfectly on Band 2 and I followed the signal path from R2 / R3 junction (wrong impedance, but a reference nonetheless) through to the anode of CR3. Hopefully self explanatory with regard to file names, scope patterns are at http://www.gatesgarth.com/scope/scope.zip Pretty stuck as to where to go next now. -- Best Regards, Chris Wilson. ___ 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] EIP545A 18GHz counter query
Very interested as I have one of these and its troubled but differently. Can't really dig in right now. Paul WB8TSL On Thu, Dec 6, 2012 at 7:33 AM, Chris Wilson wrote: > > > > Chris wrote: > > >>I have the 10MHz output from David's divider feeding the counter. When > >>fed from this the Band 2 seems unreliable starting at 10MHz. If I feed > >>it 10Mhz at 50mV from my sig gen it starts reliably. Is it a mismatch > >>from the divider, or has it perhaps not got enough drive level? > > > First, what does the counter manufacturer's specification say with > > respect to acceptable signals at the external reference input? > > > Second, what happens if you feed the TB output directly to the > > counter's reference input? > > > IIRC, the outputs of the Partridge divider are 5V TTL from a ~50 ohm > > source, so low peak-to-peak signal amplitude should not be an > > issue. If anything, the divider could be overdriving the counter's > > reference input. Note that the TTL signal ranges from 0V to ~+5V and > > does not cross ground -- if the counter is expecting the reference to > > be bipolar (i.e., if it switches on a zero-cross), it may not respond > > reliably to TTL levels. > > > Beyond that, depending on how the counter terminates the external > > reference line, you may have steps or ringing at the reference input > > (see the thread on terminations). Look at the counter's reference > > input with a high-impedance (divide by 10) scope probe to see what > > the feed looks like there. > > > Best regards, > > > Charles > > > > > 06/12/2012 12:28 > > > Here's a resume of where I am at, I hope this is sufficiently on topic > for this forum, please say if it's not. The dedicated forum for EIP > devices seems very very quiet. > > > Manual is at http://www.gatesgarth.com/EIP_545A_Service_Manual.pdf > > Saga starts with counter as received, showing just dashes, not able to > do anything more than a display test, and won't perform basic 200 MHz > test function: > > I have had a good look at board A108 the U6 chip is missing from, and > apart from a mysterious pair of multi turn pots the schematic parts > list seems to say are "not used" I can see no anomalies save for U6 > being missing altogether I'll post the results of fitting this > device. > > The replacement for the missing U6 chip arrived this morning and it > now completes the 200 MHz self test. It will read up to the limit of > my frequency generator on Band 3 which is only 1040 MHz, but looks > promising. Band 1 also works fine. > > Band 2 sort of works, but seemingly has a serious anomaly. I cannot > get Band 2 to read below 185.000 MHz. To even get over 185 MHz needs a > lot of drive power, too. 2 volts or so. Even then this somnetimes > doesn't start a display of other than zeros. If I input 184.900 it > won't read it and displays zeros. 185 and up is OK... Weird. IF > frequency? It should read from 10 MHz up to 1 GHz. It'll go to 1 GHz > plus AOK. > > > > I believe I may have isolated the issue to the A109 board. Until the > unit warms up Band 2 is deaf and needs plenty of millivolts input to > trigger, sometimes it won't trigger at all. Once warm it sometimes > settles down to near the makers spec on how much input at what > frequencies it should need to trigger. ( Seems not to > trigger at all of late, save with warming Q12) I used freeze spray to > isolate a small area, and the fine tip of a de soldering iron > connected backwards to the pump, so it blows a fine jet of hot air. > The problem is in the area marked on the schematic of board A109, > device Q12. As I have no riser board access is terribly limited. > > > It's a 2N4126 component number Q12 If I just touch it with a piece of > stiff, heavy copper wire wound round the tip of a small 15W iron, it > changes state almost immediately and the Band 2 is very sensitive > again, and immediately displays a frequency, down to 10 MHz, just > fine. As soon as it cools it reverts to the insensitive state. But > bear in mind above 185 MHz it works in a fashion hot or cold, with a > lot of drive... If the counter is left to warm up naturally and I cool > this device with some spray, it reads zeros again. > > I am not 100% sure what it's switching function is, but I have removed > it, and isolated on my Peak semiconductor tester it varies gain form > 170 cold to 190 warm, and it will suddenly go to a gain of just 4 if > it gets a bit warmer still. > > R10 is also playing up. It should be a 43K 2% but measures 32K cold > and warmed a touch changes to 4.8K ! It should have a 1 PPM/C > temperature coefficient, too, so something has happened to that as > well. > > > I am not sure if any previous abuse would have damaged diode CR1, > shown as a ND4991 ? > > > > New Q12 and new R10 fitted, problem just the same. Warming the new Q12 > brings the display back. > > Voltage tests done, results below all with a 30mV emf input to the > Band 2 socket: > > TP2 No input signal 3.4 / 3.5V Displays zeros > TP2 10 MHz 3.
Re: [time-nuts] EIP545A 18GHz counter query
> Chris wrote: >>I have the 10MHz output from David's divider feeding the counter. When >>fed from this the Band 2 seems unreliable starting at 10MHz. If I feed >>it 10Mhz at 50mV from my sig gen it starts reliably. Is it a mismatch >>from the divider, or has it perhaps not got enough drive level? > First, what does the counter manufacturer's specification say with > respect to acceptable signals at the external reference input? > Second, what happens if you feed the TB output directly to the > counter's reference input? > IIRC, the outputs of the Partridge divider are 5V TTL from a ~50 ohm > source, so low peak-to-peak signal amplitude should not be an > issue. If anything, the divider could be overdriving the counter's > reference input. Note that the TTL signal ranges from 0V to ~+5V and > does not cross ground -- if the counter is expecting the reference to > be bipolar (i.e., if it switches on a zero-cross), it may not respond > reliably to TTL levels. > Beyond that, depending on how the counter terminates the external > reference line, you may have steps or ringing at the reference input > (see the thread on terminations). Look at the counter's reference > input with a high-impedance (divide by 10) scope probe to see what > the feed looks like there. > Best regards, > Charles 06/12/2012 12:28 Here's a resume of where I am at, I hope this is sufficiently on topic for this forum, please say if it's not. The dedicated forum for EIP devices seems very very quiet. Manual is at http://www.gatesgarth.com/EIP_545A_Service_Manual.pdf Saga starts with counter as received, showing just dashes, not able to do anything more than a display test, and won't perform basic 200 MHz test function: I have had a good look at board A108 the U6 chip is missing from, and apart from a mysterious pair of multi turn pots the schematic parts list seems to say are "not used" I can see no anomalies save for U6 being missing altogether I'll post the results of fitting this device. The replacement for the missing U6 chip arrived this morning and it now completes the 200 MHz self test. It will read up to the limit of my frequency generator on Band 3 which is only 1040 MHz, but looks promising. Band 1 also works fine. Band 2 sort of works, but seemingly has a serious anomaly. I cannot get Band 2 to read below 185.000 MHz. To even get over 185 MHz needs a lot of drive power, too. 2 volts or so. Even then this somnetimes doesn't start a display of other than zeros. If I input 184.900 it won't read it and displays zeros. 185 and up is OK... Weird. IF frequency? It should read from 10 MHz up to 1 GHz. It'll go to 1 GHz plus AOK. I believe I may have isolated the issue to the A109 board. Until the unit warms up Band 2 is deaf and needs plenty of millivolts input to trigger, sometimes it won't trigger at all. Once warm it sometimes settles down to near the makers spec on how much input at what frequencies it should need to trigger. ( Seems not to trigger at all of late, save with warming Q12) I used freeze spray to isolate a small area, and the fine tip of a de soldering iron connected backwards to the pump, so it blows a fine jet of hot air. The problem is in the area marked on the schematic of board A109, device Q12. As I have no riser board access is terribly limited. It's a 2N4126 component number Q12 If I just touch it with a piece of stiff, heavy copper wire wound round the tip of a small 15W iron, it changes state almost immediately and the Band 2 is very sensitive again, and immediately displays a frequency, down to 10 MHz, just fine. As soon as it cools it reverts to the insensitive state. But bear in mind above 185 MHz it works in a fashion hot or cold, with a lot of drive... If the counter is left to warm up naturally and I cool this device with some spray, it reads zeros again. I am not 100% sure what it's switching function is, but I have removed it, and isolated on my Peak semiconductor tester it varies gain form 170 cold to 190 warm, and it will suddenly go to a gain of just 4 if it gets a bit warmer still. R10 is also playing up. It should be a 43K 2% but measures 32K cold and warmed a touch changes to 4.8K ! It should have a 1 PPM/C temperature coefficient, too, so something has happened to that as well. I am not sure if any previous abuse would have damaged diode CR1, shown as a ND4991 ? New Q12 and new R10 fitted, problem just the same. Warming the new Q12 brings the display back. Voltage tests done, results below all with a 30mV emf input to the Band 2 socket: TP2 No input signal 3.4 / 3.5V Displays zeros TP2 10 MHz 3.4 / 3.5V Displays zeros TP2 50 MHz 3.4 / 3.5 V Displays zeros TP2 100 MHz 3.4 / 3.5V Displays zeros TP2 400 MHz 3.4 / 3.5V Displays zeros TP2 500 MHz 0.06V Displays frequency TP2 900 MHz 4.9 / 5.0V Displays frequency For TP2 the change over seems circa 450MHz *** BUT *** Input 650 MHZ and TP2 shows 4.2 / 4.3V a
Re: [time-nuts] EIP545A 18GHz counter query
Could be either. What is the band width of Band 2? I am not in front of my counter. Joe -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Chris Wilson Sent: Thursday, November 29, 2012 9:57 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] EIP545A 18GHz counter query > 29/11/2012 09:30 > The replacement for the missing U6 chip arrived this morning and it > now completes the 200 MHz self test It will read up to the limit of my > frequency generator on Band 3 which is only 1040 MHz, but looks > promising. > Band 2 also works, but seemingly has an anomaly. I cannot get Band 2 > to read below 185.000 MHz. If I input 184.900 it won't read it and > displays zeros. 185 and up is OK... Weird. It should read from 10 MHz > up to 1 GHz. It'll go to 1 GHz plus AOK. > Band 1 appears to work fine. > These tests are with both my GPS referenced external standard and the > internal reference used. > So Band 2 appears to have a further issue. Will refer to the manual > and see if I can fathom it out. Any ideas as to why Band 2 will only > read from 185 MHz upwards please? Thanks. 29/11/2012 15:53 OK, I may be doing something foolish. David Partridge was able to supply one of his last remaining frequency dividers to me, for use with my TB GPS standard. It works perfectly and is now in a nice enclosure feeding a small array of BNC sockets on my shack wall. I take the 10 MHz output of the Thunderbolt into David's frequency divider: http://www.perdrix.co.uk/FrequencyDivider/index.html I have the 10MHz output from David's divider feeding the counter. When fed from this the Band 2 seems unreliable starting at 10MHz. If I feed it 10Mhz at 50mV from my sig gen it starts reliably. Is it a mismatch from the divider, or has it perhaps not got enough drive level? -- Best Regards, Chris Wilson. ___ 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] EIP545A 18GHz counter query
Chris wrote: Band 2 should work from -20dbm (22mV RMS) right across its 10 MHz to 1 GHz range according to the manual. Even with 190 MHz into it it takes at least 30mV to start triggering, sometimes up to 40 mV. 40 mV will reliably fire it across its full range once it warms up a bit. Band 1 specs are 22 mV from 10Hz to 1 GHz, and that band triggers with just 15 mV at 10 MHz, but needs 25 mV at 100 MHz. Band 3 specs are 12 mV at 1 GHz to 1.2 GHz (needs 15 mV @ 1GHz) Ahh, I had missed that you were feeding the 10 MHz from the divider to the *measurement* inputs. It sounds like a triggering issue. Is the trigger coupling switchable from DC to AC, and is it adjustable for trigger level? It is not unusual for the trigger point to drift a bit as a counter warms up, but at any temperature you should be able to find settings that will allow it to trigger on inputs at least close to the minimum the manufacturer specifies. The figures you are seeing are not way out of bounds, especially if the trigger coupling and level have not been adjusted for optimum triggering. Again, note that the divider output is unipolar (positive-only, does not cross 0V). With a TTL input, you should get good, stable triggering with the trigger coupling set to DC and the trigger level set to ~+0.5V on the positive-going edge. With sine-wave inputs, you may get best results with AC coupling and a trigger level at or near 0V. Look under "triggering" in the manual to see what the manufacturer recommends. It's just like the triggering on an oscilloscope, if that helps -- what you would do to get a stable scope display is also what you need to do to get a stable frequency reading. Best regards, Charles ___ 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] EIP545A 18GHz counter query
> Chris wrote: >>I have the 10MHz output from David's divider feeding the counter. When >>fed from this the Band 2 seems unreliable starting at 10MHz. If I feed >>it 10Mhz at 50mV from my sig gen it starts reliably. Is it a mismatch >>from the divider, or has it perhaps not got enough drive level? > First, what does the counter manufacturer's specification say with > respect to acceptable signals at the external reference input? > Second, what happens if you feed the TB output directly to the > counter's reference input? > IIRC, the outputs of the Partridge divider are 5V TTL from a ~50 ohm > source, so low peak-to-peak signal amplitude should not be an > issue. If anything, the divider could be overdriving the counter's > reference input. Note that the TTL signal ranges from 0V to ~+5V and > does not cross ground -- if the counter is expecting the reference to > be bipolar (i.e., if it switches on a zero-cross), it may not respond > reliably to TTL levels. > Beyond that, depending on how the counter terminates the external > reference line, you may have steps or ringing at the reference input > (see the thread on terminations). Look at the counter's reference > input with a high-impedance (divide by 10) scope probe to see what > the feed looks like there. > Best regards, > Charles 29/11/2012 17:32 It's definitely playing up, and I don't think I have it right with regard to it being because I am feeding it from David's divider. I let it go cold this afternoon and have just come to it now. Even with the signal into Band 2 direct from my sig gen at 1 volt it doesn't start counting unless I go to, or over, 185 MHz. Band 3 is fine from cold, as is Band 1. I'll get some freeze spray and see if I can isolate any part. I'll also have a go with the air line. So near to being fine, must be something pretty minor? Band 2 should work from -20dbm (22mV RMS) right across its 10 MHz to 1 GHz range according to the manual. Even with 190 MHz into it it takes at least 30mV to start triggering, sometimes up to 40 mV. 40 mV will reliably fire it across its full range once it warms up a bit. Band 1 specs are 22 mV from 10Hz to 1 GHz, and that band triggers with just 15 mV at 10 MHz, but needs 25 mV at 100 MHz. Band 3 specs are 12 mV at 1 GHz to 1.2 GHz (needs 15 mV @ 1GHz) 1.2 to 12.4 GHz should trigger at 7 mV but my sig gen stops at 1040 MHz so can't test. Thanks for your input Charles. -- Best Regards, Chris Wilson. ___ 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] EIP545A 18GHz counter query
OK. It maybe time for the hair dryer and freeze spray. Also, try re-seating any socketed chips. -John == > > >> It sounds like a SW limit, not hardware. > >> Silly question: Have you read the manual? > >> -John > > > > > 29/11/2012 15:31 > > Hi John, will re read the section on limits, but please see my reply > to Chuck I just posted. Cheers. > > > > -- >Best Regards, >Chris Wilson. > > > ___ > 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] EIP545A 18GHz counter query
Hmmm you run the risk of deafening the counter with 5Vpp (2.5V into 50R). Dave -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Chris Wilson Sent: 29 November 2012 15:57 To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] EIP545A 18GHz counter query > 29/11/2012 09:30 > The replacement for the missing U6 chip arrived this morning and it > now completes the 200 MHz self test It will read up to the limit of my > frequency generator on Band 3 which is only 1040 MHz, but looks > promising. > Band 2 also works, but seemingly has an anomaly. I cannot get Band 2 > to read below 185.000 MHz. If I input 184.900 it won't read it and > displays zeros. 185 and up is OK... Weird. It should read from 10 MHz > up to 1 GHz. It'll go to 1 GHz plus AOK. > Band 1 appears to work fine. > These tests are with both my GPS referenced external standard and the > internal reference used. > So Band 2 appears to have a further issue. Will refer to the manual > and see if I can fathom it out. Any ideas as to why Band 2 will only > read from 185 MHz upwards please? Thanks. 29/11/2012 15:53 OK, I may be doing something foolish. David Partridge was able to supply one of his last remaining frequency dividers to me, for use with my TB GPS standard. It works perfectly and is now in a nice enclosure feeding a small array of BNC sockets on my shack wall. I take the 10 MHz output of the Thunderbolt into David's frequency divider: http://www.perdrix.co.uk/FrequencyDivider/index.html I have the 10MHz output from David's divider feeding the counter. When fed from this the Band 2 seems unreliable starting at 10MHz. If I feed it 10Mhz at 50mV from my sig gen it starts reliably. Is it a mismatch from the divider, or has it perhaps not got enough drive level? -- Best Regards, Chris Wilson. ___ 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] EIP545A 18GHz counter query
Chris wrote: I have the 10MHz output from David's divider feeding the counter. When fed from this the Band 2 seems unreliable starting at 10MHz. If I feed it 10Mhz at 50mV from my sig gen it starts reliably. Is it a mismatch from the divider, or has it perhaps not got enough drive level? First, what does the counter manufacturer's specification say with respect to acceptable signals at the external reference input? Second, what happens if you feed the TB output directly to the counter's reference input? IIRC, the outputs of the Partridge divider are 5V TTL from a ~50 ohm source, so low peak-to-peak signal amplitude should not be an issue. If anything, the divider could be overdriving the counter's reference input. Note that the TTL signal ranges from 0V to ~+5V and does not cross ground -- if the counter is expecting the reference to be bipolar (i.e., if it switches on a zero-cross), it may not respond reliably to TTL levels. Beyond that, depending on how the counter terminates the external reference line, you may have steps or ringing at the reference input (see the thread on terminations). Look at the counter's reference input with a high-impedance (divide by 10) scope probe to see what the feed looks like there. Best regards, Charles ___ 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] EIP545A 18GHz counter query
> 29/11/2012 09:30 > The replacement for the missing U6 chip arrived this morning and it > now completes the 200 MHz self test It will read up to the limit of my > frequency generator on Band 3 which is only 1040 MHz, but looks > promising. > Band 2 also works, but seemingly has an anomaly. I cannot get Band 2 > to read below 185.000 MHz. If I input 184.900 it won't read it and > displays zeros. 185 and up is OK... Weird. It should read from 10 MHz > up to 1 GHz. It'll go to 1 GHz plus AOK. > Band 1 appears to work fine. > These tests are with both my GPS referenced external standard and the > internal reference used. > So Band 2 appears to have a further issue. Will refer to the manual > and see if I can fathom it out. Any ideas as to why Band 2 will only > read from 185 MHz upwards please? Thanks. 29/11/2012 15:53 OK, I may be doing something foolish. David Partridge was able to supply one of his last remaining frequency dividers to me, for use with my TB GPS standard. It works perfectly and is now in a nice enclosure feeding a small array of BNC sockets on my shack wall. I take the 10 MHz output of the Thunderbolt into David's frequency divider: http://www.perdrix.co.uk/FrequencyDivider/index.html I have the 10MHz output from David's divider feeding the counter. When fed from this the Band 2 seems unreliable starting at 10MHz. If I feed it 10Mhz at 50mV from my sig gen it starts reliably. Is it a mismatch from the divider, or has it perhaps not got enough drive level? -- Best Regards, Chris Wilson. ___ 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] EIP545A 18GHz counter query
> It sounds like a SW limit, not hardware. > Silly question: Have you read the manual? > -John 29/11/2012 15:31 Hi John, will re read the section on limits, but please see my reply to Chuck I just posted. Cheers. -- Best Regards, Chris Wilson. ___ 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] EIP545A 18GHz counter query
It sounds like a SW limit, not hardware. Silly question: Have you read the manual? -John = > > 29/11/2012 09:30 > > The replacement for the missing U6 chip arrived this morning and it > now completes the 200 MHz self test It will read up to the limit of my > frequency generator on Band 3 which is only 1040 MHz, but looks > promising. > > Band 2 also works, but seemingly has an anomaly. I cannot get Band 2 > to read below 185.000 MHz. If I input 184.900 it won't read it and > displays zeros. 185 and up is OK... Weird. It should read from 10 MHz > up to 1 GHz. It'll go to 1 GHz plus AOK. > > Band 1 appears to work fine. > > These tests are with both my GPS referenced external standard and the > internal reference used. > > So Band 2 appears to have a further issue. Will refer to the manual > and see if I can fathom it out. Any ideas as to why Band 2 will only > read from 185 MHz upwards please? Thanks. > > > -- >Best Regards, >Chris Wilson. > > > ___ > 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] EIP545A 18GHz counter query
I had the same problem with my 545A, and it turned out to be a tin whisker thing. Scrub both the GPIB card, and the main controller card with a brush, and then blow them off with compressed air. Try to get the air close to each chip and socket, and blow from all angles. Plug the cards back in, and I think you will be in for a pleasant surprise. -Chuck Harris Chris Wilson wrote: Chris, Put a ohmmeter across any of the capacitors on the GPIB board and see what the resistance is. Since that kills the unit, I suspect the resistance is low (?shorted tantalum) or there is a problem with one of the chips that takes the 5 VDC buss down. Make sure of the polarity of your DMM, + to + and - to ground. Alternatively, there is a short on the +5 VDC line at the connector on the mother board that is 'actuated' by plugging the board in. Measure the resistance to ground of the +5 VDC buss (power off) with the GPIB board plugged in and not plugged in. Joe Thanks again Joe, checked the tants on the GPIB board and they seem fine, have put this aside until the rest is AOK. Then I'll pull the chips one by one and try and isolate the issue. The 5 v bus seems good with the board in or out, too. 29/11/2012 09:27 ___ 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] EIP545A 18GHz counter query
29/11/2012 09:30 The replacement for the missing U6 chip arrived this morning and it now completes the 200 MHz self test It will read up to the limit of my frequency generator on Band 3 which is only 1040 MHz, but looks promising. Band 2 also works, but seemingly has an anomaly. I cannot get Band 2 to read below 185.000 MHz. If I input 184.900 it won't read it and displays zeros. 185 and up is OK... Weird. It should read from 10 MHz up to 1 GHz. It'll go to 1 GHz plus AOK. Band 1 appears to work fine. These tests are with both my GPS referenced external standard and the internal reference used. So Band 2 appears to have a further issue. Will refer to the manual and see if I can fathom it out. Any ideas as to why Band 2 will only read from 185 MHz upwards please? Thanks. -- Best Regards, Chris Wilson. ___ 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] EIP545A 18GHz counter query
> Chris, > Put a ohmmeter across any of the capacitors on the GPIB board and see what > the resistance is. Since that kills the unit, I suspect the resistance is > low (?shorted tantalum) or there is a problem with one of the chips that > takes the 5 VDC buss down. Make sure of the polarity of your DMM, + to + > and - to ground. > Alternatively, there is a short on the +5 VDC line at the connector on the > mother board that is 'actuated' by plugging the board in. Measure the > resistance to ground of the +5 VDC buss (power off) with the GPIB board > plugged in and not plugged in. > Joe Thanks again Joe, checked the tants on the GPIB board and they seem fine, have put this aside until the rest is AOK. Then I'll pull the chips one by one and try and isolate the issue. The 5 v bus seems good with the board in or out, too. 29/11/2012 09:27 -- Best Regards, Chris Wilson. ___ 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] EIP545A 18GHz counter query
Chris, Put a ohmmeter across any of the capacitors on the GPIB board and see what the resistance is. Since that kills the unit, I suspect the resistance is low (?shorted tantalum) or there is a problem with one of the chips that takes the 5 VDC buss down. Make sure of the polarity of your DMM, + to + and - to ground. Alternatively, there is a short on the +5 VDC line at the connector on the mother board that is 'actuated' by plugging the board in. Measure the resistance to ground of the +5 VDC buss (power off) with the GPIB board plugged in and not plugged in. Joe -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Chris Wilson Sent: Tuesday, November 27, 2012 4:20 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] EIP545A 18GHz counter query > Hi Chris, > The first thing you should do is join the EIP_Microwave group at > yahoo: > http://tech.groups.yahoo.com/group/EIP_Microwave > There's lots of info and help there for EIP counters. > Don't worry about the signature analyzer for now. It would normally > be used if the processor was dead. The fact that Band 1 works means > that the processor/memory is okay. If the processor / memory / > display related diagnostics like 02, 03, 04, 05 also pass, then > signature analysis is unlikely to tell you anything more. > The first thing you have to do is replace that missing chip. Bands 2 > and 3 require the VCO and phase-lock circuitry to be working. As far as > I can see, U6 is not optional. Until the 200 MHz test passes, you can't > get any further. Be sure to check for obvious problems. I bought a > 545A parts unit that wouldn't pass the 200 MHz test. It turned out that > some of the board-to-board cables were plugged into the wrong connectors! > I'm in the same position as you regarding testing at high frequencies. > You might be able to get a signal at the second or third harmonic of > your generator by cranking the level to the maximum and then using the > counter's Band 3 frequency limits feature to only look at that > frequency. My HP 8647A only goes to 1 GHz, but I can see harmonics up > to 3 GHz. I've also picked up a few cheap YIG oscillators that have > allowed me to test in the 1-10 GHz range. Watch out for the signal > levels. YIG oscillators have lots of output! > By the way, I'd be reluctant to purchase anything else from that > vendor. Chips don't evaporate overnight. Mind you, I guess chips have > fallen out of sockets. Any strange rattling noises when you shake it? :-) > Ed 27/11/2012 22:08 Thanks Ed, someone else kindly e-mailed me and told me of the existence of the Yahoo reflector for EIP equipment. Sadly U6 is definitely not rattling about in the case :( Happily I didn't pay a lot for this thing :) I have had all the boards out and double checked all the cables are correctly connected. The only issue apart from the missing chip is that installing the GPIB board kills the thing completely. I am not sure why, but I can live without that. It seems it may the power meter and DAC options, at least the buttons are present, but pressing them gives Error 13. Are the buttons present on all the front panels? The processor, memory and display tests pass AOK. If I get it running further I may try and boorow a friends microwave sig gen, rather than try getting clever and break it agin with too high an input signal. Thanks very much for the tips Ed, much appreciated. -- Best Regards, Chris Wilson. ___ 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] EIP545A 18GHz counter query
Boy great thread running here. I have a number of older EIPs that all work and have been repaired. Hard to pass up the $25ers. I also have several newer ones 545 and 585s. EIP became a bit more clever on these in how they process the YIG signals and thats the place I am having issues on all 3. Its one of those "I'll have to get back to that soon". Lots of good comments in the thread. Thanks Paul WB8TSL On Tue, Nov 27, 2012 at 5:20 PM, Chris Wilson wrote: > > > > Hi Chris, > > > The first thing you should do is join the EIP_Microwave group at yahoo: > > > http://tech.groups.yahoo.com/group/EIP_Microwave > > > There's lots of info and help there for EIP counters. > > > Don't worry about the signature analyzer for now. It would normally be > > used if the processor was dead. The fact that Band 1 works means that > > the processor/memory is okay. If the processor / memory / display > > related diagnostics like 02, 03, 04, 05 also pass, then signature > > analysis is unlikely to tell you anything more. > > > The first thing you have to do is replace that missing chip. Bands 2 > > and 3 require the VCO and phase-lock circuitry to be working. As far as > > I can see, U6 is not optional. Until the 200 MHz test passes, you can't > > get any further. Be sure to check for obvious problems. I bought a > > 545A parts unit that wouldn't pass the 200 MHz test. It turned out that > > some of the board-to-board cables were plugged into the wrong connectors! > > > I'm in the same position as you regarding testing at high frequencies. > > You might be able to get a signal at the second or third harmonic of > > your generator by cranking the level to the maximum and then using the > > counter's Band 3 frequency limits feature to only look at that > > frequency. My HP 8647A only goes to 1 GHz, but I can see harmonics up > > to 3 GHz. I've also picked up a few cheap YIG oscillators that have > > allowed me to test in the 1-10 GHz range. Watch out for the signal > > levels. YIG oscillators have lots of output! > > > By the way, I'd be reluctant to purchase anything else from that > > vendor. Chips don't evaporate overnight. Mind you, I guess chips have > > fallen out of sockets. Any strange rattling noises when you shake it? > :-) > > > Ed > > > > > 27/11/2012 22:08 > > > Thanks Ed, someone else kindly e-mailed me and told me of the > existence of the Yahoo reflector for EIP equipment. Sadly U6 is > definitely not rattling about in the case :( Happily I didn't pay a > lot for this thing :) > > I have had all the boards out and double checked all the cables are > correctly connected. The only issue apart from the missing chip is > that installing the GPIB board kills the thing completely. I am not > sure why, but I can live without that. > > It seems it may the power meter and DAC options, at least the buttons > are present, but pressing them gives Error 13. Are the buttons present > on all the front panels? > > The processor, memory and display tests pass AOK. > > If I get it running further I may try and boorow a friends microwave > sig gen, rather than try getting clever and break it agin with too > high an input signal. Thanks very much for the tips Ed, much > appreciated. > > > > > -- >Best Regards, >Chris Wilson. > > > ___ > 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] EIP545A 18GHz counter query
> Hi Chris, > The first thing you should do is join the EIP_Microwave group at yahoo: > http://tech.groups.yahoo.com/group/EIP_Microwave > There's lots of info and help there for EIP counters. > Don't worry about the signature analyzer for now. It would normally be > used if the processor was dead. The fact that Band 1 works means that > the processor/memory is okay. If the processor / memory / display > related diagnostics like 02, 03, 04, 05 also pass, then signature > analysis is unlikely to tell you anything more. > The first thing you have to do is replace that missing chip. Bands 2 > and 3 require the VCO and phase-lock circuitry to be working. As far as > I can see, U6 is not optional. Until the 200 MHz test passes, you can't > get any further. Be sure to check for obvious problems. I bought a > 545A parts unit that wouldn't pass the 200 MHz test. It turned out that > some of the board-to-board cables were plugged into the wrong connectors! > I'm in the same position as you regarding testing at high frequencies. > You might be able to get a signal at the second or third harmonic of > your generator by cranking the level to the maximum and then using the > counter's Band 3 frequency limits feature to only look at that > frequency. My HP 8647A only goes to 1 GHz, but I can see harmonics up > to 3 GHz. I've also picked up a few cheap YIG oscillators that have > allowed me to test in the 1-10 GHz range. Watch out for the signal > levels. YIG oscillators have lots of output! > By the way, I'd be reluctant to purchase anything else from that > vendor. Chips don't evaporate overnight. Mind you, I guess chips have > fallen out of sockets. Any strange rattling noises when you shake it? :-) > Ed 27/11/2012 22:08 Thanks Ed, someone else kindly e-mailed me and told me of the existence of the Yahoo reflector for EIP equipment. Sadly U6 is definitely not rattling about in the case :( Happily I didn't pay a lot for this thing :) I have had all the boards out and double checked all the cables are correctly connected. The only issue apart from the missing chip is that installing the GPIB board kills the thing completely. I am not sure why, but I can live without that. It seems it may the power meter and DAC options, at least the buttons are present, but pressing them gives Error 13. Are the buttons present on all the front panels? The processor, memory and display tests pass AOK. If I get it running further I may try and boorow a friends microwave sig gen, rather than try getting clever and break it agin with too high an input signal. Thanks very much for the tips Ed, much appreciated. -- Best Regards, Chris Wilson. ___ 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] EIP545A 18GHz counter query
Hi Ed: I have one of these too; it takes in about 200 MHz, output 0.4-1.8 GHz. ten ohm coil, also a heater at 28 v. I also have a filter that uses about the same voltage/current. I did find an LED/battery charger module from China, pretty cheap, that purports to be pwm adjustable; we'll see. I'll try driving it with an Arduino. Don Ed Palmer > Hi Don, > > Yes, I've heard of SRDs. I think every Rb standard uses them. I > recently purchased a YIG Multiplier that includes an SRD followed by a > YIG filter. But, from my reading, there are some significant issues > that you run into when driving an SRD. I'm still playing with mine. > > Ed > > On 11/27/2012 2:15 PM, Don Latham wrote: >> snip >>> I'm in the same position as you regarding testing at high >>> frequencies. >>> You might be able to get a signal at the second or third harmonic of >>> your generator by cranking the level to the maximum and then using >>> the >>> counter's Band 3 frequency limits feature to only look at that >>> frequency. >> snip >> You can also get a step recovery diode and generate a bunch of >> harmonics... >> DonL >> > > > ___ > 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. > -- "Neither the voice of authority nor the weight of reason and argument are as significant as experiment, for thence comes quiet to the mind." De Erroribus Medicorum, R. Bacon, 13th century. "If you don't know what it is, don't poke it." Ghost in the Shell Dr. Don Latham AJ7LL Six Mile Systems LLP 17850 Six Mile Road POB 134 Huson, MT, 59846 VOX 406-626-4304 www.lightningforensics.com www.sixmilesystems.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.
Re: [time-nuts] EIP545A 18GHz counter query
You can also overdrive a mmic and get good results. That is what I'm using as the oscillator for my 1.296 GHz beacon. Bob On Nov 27, 2012, at 15:45, Ed Palmer wrote: > Hi Don, > > Yes, I've heard of SRDs. I think every Rb standard uses them. I recently > purchased a YIG Multiplier that includes an SRD followed by a YIG filter. > But, from my reading, there are some significant issues that you run into > when driving an SRD. I'm still playing with mine. > > Ed > > On 11/27/2012 2:15 PM, Don Latham wrote: >> snip >>> I'm in the same position as you regarding testing at high frequencies. >>> You might be able to get a signal at the second or third harmonic of >>> your generator by cranking the level to the maximum and then using the >>> counter's Band 3 frequency limits feature to only look at that >>> frequency. >> snip >> You can also get a step recovery diode and generate a bunch of harmonics... >> DonL > > > ___ > 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] EIP545A 18GHz counter query
Hi Don, Yes, I've heard of SRDs. I think every Rb standard uses them. I recently purchased a YIG Multiplier that includes an SRD followed by a YIG filter. But, from my reading, there are some significant issues that you run into when driving an SRD. I'm still playing with mine. Ed On 11/27/2012 2:15 PM, Don Latham wrote: snip I'm in the same position as you regarding testing at high frequencies. You might be able to get a signal at the second or third harmonic of your generator by cranking the level to the maximum and then using the counter's Band 3 frequency limits feature to only look at that frequency. snip You can also get a step recovery diode and generate a bunch of harmonics... DonL ___ 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] EIP545A 18GHz counter query
snip > I'm in the same position as you regarding testing at high frequencies. > You might be able to get a signal at the second or third harmonic of > your generator by cranking the level to the maximum and then using the > counter's Band 3 frequency limits feature to only look at that > frequency. snip You can also get a step recovery diode and generate a bunch of harmonics... DonL -- "Neither the voice of authority nor the weight of reason and argument are as significant as experiment, for thence comes quiet to the mind." De Erroribus Medicorum, R. Bacon, 13th century. "If you don't know what it is, don't poke it." Ghost in the Shell Dr. Don Latham AJ7LL Six Mile Systems LLP 17850 Six Mile Road POB 134 Huson, MT, 59846 VOX 406-626-4304 www.lightningforensics.com www.sixmilesystems.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.
Re: [time-nuts] EIP545A 18GHz counter query
Hi Chris, The first thing you should do is join the EIP_Microwave group at yahoo: http://tech.groups.yahoo.com/group/EIP_Microwave There's lots of info and help there for EIP counters. Don't worry about the signature analyzer for now. It would normally be used if the processor was dead. The fact that Band 1 works means that the processor/memory is okay. If the processor / memory / display related diagnostics like 02, 03, 04, 05 also pass, then signature analysis is unlikely to tell you anything more. The first thing you have to do is replace that missing chip. Bands 2 and 3 require the VCO and phase-lock circuitry to be working. As far as I can see, U6 is not optional. Until the 200 MHz test passes, you can't get any further. Be sure to check for obvious problems. I bought a 545A parts unit that wouldn't pass the 200 MHz test. It turned out that some of the board-to-board cables were plugged into the wrong connectors! I'm in the same position as you regarding testing at high frequencies. You might be able to get a signal at the second or third harmonic of your generator by cranking the level to the maximum and then using the counter's Band 3 frequency limits feature to only look at that frequency. My HP 8647A only goes to 1 GHz, but I can see harmonics up to 3 GHz. I've also picked up a few cheap YIG oscillators that have allowed me to test in the 1-10 GHz range. Watch out for the signal levels. YIG oscillators have lots of output! By the way, I'd be reluctant to purchase anything else from that vendor. Chips don't evaporate overnight. Mind you, I guess chips have fallen out of sockets. Any strange rattling noises when you shake it? :-) Ed On 11/27/2012 8:37 AM, Chris Wilson wrote: 27/11/2012 14:18 I bought a 18GHz EIP545A counter which the vendor said was working fine the day before and when on overnight soak test, and also when last used some months agao. But when he checked it on the morning of my coming over to see it he found it had developed a fault... I bought it off him cheaply, as seen, hoping it might be fixable. Here's the basic tale: It was acquired displaying just dashes. I checked the PSU voltages and found the PSU section outputting well away from the manual figures. I corrected these and checked supplies for ripple and they were all good. I then decided to remove any board that was not essential to operation. It came with a GPIB option board, so I pulled it. Luckily this did some good and a working display appeared. There were three tantalum caps on this board, as a matter of interest I pulled a leg on each and tested them, all were OK. Refitting it killed the display back to "dashes" again, so I set it aside as having an "unknown fault", and continued. I can get it to accurately display up to EXACTLY 188. MHz. Inputting 190. MHz gives zeros. It has three frequency bands. Band one works perfectly right up and well beyond its 10Hz to 100MHz range. Band two often doesn't work at all, and just diplays zeros, it's a 50 ohm input, compared to the 1meg 20pF Band 1 input. Sometimes by ramping the frequency up slowly from 100 MHz I can get a seemingly random reading. Band 3, the GHz range, doesn't work at all. Again, only zeros are displayed. The machine has quite a good range of self diagnosis tests. Tests are via the key pad. The first test checks the VCO and other stuff, and should display an accurate 200. MHz. It displays well over, always in the range 253.5 and the display isn't stable, it hovers over several KHz. There's a tree menu to see where this issue could lie. One limb suggests using a known good counter on the output of the VCO. I did this and the output is miles high in frequency, about double, and unstable. The tree menus goes on to suggest a phase lock circuitry fault. Further tests seem to depend in part upon using something called a Signature Analyser, which I have never even heard of They suggest an HP5004A, which is apparently pretty ancient. Is there a cheap way of acquiring something to do this sort of testing? I believe given a few pointers my scope, multi meter, sig gen and my other (working) Racal counter could take me further. It's a nice old thing, and I would quite like a means of counting into the higher frequencies it offers, but don't want to spend too much time or money on it. It works a damned sight more than when it first landed, which has kind of given me incentive to push a bit further, given I have a .pdf copy of the repair manual. Here's the page of the schematic I think is relevant, if it is a phase locked loop problem. This morning I realised there's a chip missing from a socket on the board in question. It's U6, a flip flop, part of the pre scaler I think? I assumed it was for some option, not fitted, but I am not so sure now. A Chinese Ebay seller is breaking one of these machines and he lists all the boards seperately, with decent photos. His board has this socket populated, an
Re: [time-nuts] EIP545A 18GHz counter query
EIP was like many smaller T&M companies, they by virtue of the size of lack of the desire to research component, manufacturing, life cycle testing, TQM, etc, etc. produced great instruments the day they were made. After that things went down hill. BTW, the big boys would forget all the above from time to time as well. What's that about history and repeating ? Having said that Chucks recommendation covers a lot of the issues, I've have over the year a dozen EIP and the socket/tin issue was one of the top 5 or so issues. Another is the power supplies specially around the pass transistors/regulators. A bit more air flow would have been suggested. But that's not just EIP. A couple other steps on the whisker issue, get a good stiff brush go over the whole board. If you don't own an air compressor get a cheap OIL LESS one. Remember the words OIL LESS. IF not invest in a OIL separator. Dont only blow around the connectors and under them. Once you worked around all the suspect parts, "wash" over the board with the compressed air starting at one corner and ending up at its opposing end. If you don't you run the chance of depositing the 'short' to a different place. BTW did i mention OIL LESS ? .. I've serviced quite a few instruments that when I got them had a nice ultra thin layer of sticky all over them. Sorry for the rant, all memories of T&M repair were not the best :-) -pete On Tue, Nov 27, 2012 at 7:45 AM, Chuck Harris wrote: > This one is usually an easy fix. The EPROMS on the controller > card are using tin plated sockets, and they become tin-whisker > cities. The counter will usually have enough oomph to blow any > transient whiskers away if it is left running, but if it sits > the whiskers will grow quickly and prevent the CPU from passing > its power on self-test, and you get the "--" display. > > Take a high pressure air gun and blow under, around and through > the EPROM sockets from all directions and angles. When you plug > the board back in, it should start to work again... for a while. > > A more permanent fix involves removing the sockets and replacing > them with gold plated sockets with machined pins. > > Also, on many of the 545A counters there is a design mistake on > the power supply board where the wire tie that holds an electrolytic > capacitor passes through the board. The holes the wire tie passes > through are plated, and come through alongside of the +9V unregulated > traces... bringing ground and +9V together. Drill or file the plating > out of the holes to prevent spurious blowing of the mains fuse. > > -Chuck Harris > > > Chris Wilson wrote: >> >> >> >>27/11/2012 14:18 >> >> I bought a 18GHz EIP545A counter which the vendor said was working >> fine the day before and when on overnight soak test, and also when >> last used some months agao. But when he checked it on the morning of >> my coming over to see it he found it had developed a fault... I bought >> it off him cheaply, as seen, hoping it might be fixable. >> >> >> Here's the basic tale: >> >> It was acquired displaying just dashes. I checked the PSU voltages and >> found the PSU section outputting well away from the manual figures. I >> corrected these and checked supplies for ripple and they were all >> good. I then decided to remove any board that was not essential to >> operation. It came with a GPIB option board, so I pulled it. Luckily >> this did some good and a working display appeared. There were three >> tantalum caps on this board, as a matter of interest I pulled a leg on >> each and tested them, all were OK. Refitting it killed the display >> back to "dashes" again, so I set it aside as having an "unknown >> fault", and continued. I can get it to accurately display up to >> EXACTLY 188. MHz. Inputting 190. MHz gives zeros. It has three >> frequency bands. Band one works perfectly right up and well beyond its >> 10Hz to 100MHz range. Band two often doesn't work at all, and just >> diplays zeros, it's a 50 ohm input, compared to the 1meg 20pF Band 1 >> input. Sometimes by ramping the frequency up slowly from 100 MHz I can get >> a >> seemingly random reading. Band 3, the GHz range, doesn't work at >> all. Again, only zeros are displayed. >> >> The machine has quite a good range of self diagnosis tests. Tests are >> via the key pad. The first test checks the VCO and other stuff, and >> should display an accurate 200. MHz. It displays well over, always >> in the range 253.5 and the display isn't stable, it hovers over >> several KHz. There's a tree menu to see where this issue could lie. >> One limb suggests using a known good counter on the output of the VCO. >> I did this and the output is miles high in frequency, about double, >> and unstable. The tree menus goes on to suggest a phase lock circuitry >> fault. >> >> Further tests seem to depend in part upon using something called a >> Signature Analyser, which I have never even heard of They suggest an >> HP5004A, which is apparent
Re: [time-nuts] EIP545A 18GHz counter query
It is also used to check ROMs and RAMs for good data. The service manual will often contain 'signatures' for each pinout of a device, as it runs through a set, respective routine. Specific start, stop, and clock signals are defined in the service manual. A very valuable tool. I have a 5005A. Also comes equipped with a voltmeter, ohmmeter and counter. Nothing a nice logic analyzer can't do, ...just simpler and quicker. -Don -- From: "Bob Quenelle" Sent: Tuesday, November 27, 2012 10:05 AM To: "Discussion of precise time and frequency measurement" Subject: Re: [time-nuts] EIP545A 18GHz counter query > Not that it's likely to help you, but a signature analyzer uses a shift > register with feedback to generate a 4 hex character "signature" from a > serial data stream. It would only help if the troubleshooting tree includes > a list a bad signatures for specific failures. > http://www.prc68.com/I/HP5004.shtml > Bob > > -Original Message- > From: Chuck Harris > Sent: Tuesday, November 27, 2012 7:45 AM > To: Chris Wilson ; Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] EIP545A 18GHz counter query > > This one is usually an easy fix. The EPROMS on the controller > card are using tin plated sockets, and they become tin-whisker > cities. The counter will usually have enough oomph to blow any > transient whiskers away if it is left running, but if it sits > the whiskers will grow quickly and prevent the CPU from passing > its power on self-test, and you get the "--" display. > > Take a high pressure air gun and blow under, around and through > the EPROM sockets from all directions and angles. When you plug > the board back in, it should start to work again... for a while. > > A more permanent fix involves removing the sockets and replacing > them with gold plated sockets with machined pins. > > Also, on many of the 545A counters there is a design mistake on > the power supply board where the wire tie that holds an electrolytic > capacitor passes through the board. The holes the wire tie passes > through are plated, and come through alongside of the +9V unregulated > traces... bringing ground and +9V together. Drill or file the plating > out of the holes to prevent spurious blowing of the mains fuse. > > -Chuck Harris > > Chris Wilson wrote: >> >> >>27/11/2012 14:18 >> >> I bought a 18GHz EIP545A counter which the vendor said was working >> fine the day before and when on overnight soak test, and also when >> last used some months ago. But when he checked it on the morning of >> my coming over to see it he found it had developed a fault... I bought >> it off him cheaply, as seen, hoping it might be fixable. >> >> >> Here's the basic tale: >> >> It was acquired displaying just dashes. I checked the PSU voltages and >> found the PSU section outputting well away from the manual figures. I >> corrected these and checked supplies for ripple and they were all >> good. I then decided to remove any board that was not essential to >> operation. It came with a GPIB option board, so I pulled it. Luckily >> this did some good and a working display appeared. There were three >> tantalum caps on this board, as a matter of interest I pulled a leg on >> each and tested them, all were OK. Refitting it killed the display >> back to "dashes" again, so I set it aside as having an "unknown >> fault", and continued. I can get it to accurately display up to >> EXACTLY 188. MHz Inputting 190. MHz gives zeros. It has three >> frequency bands. Band one works perfectly right up and well beyond its >> 10 Hz to 100 MHz range. Band two often doesn't work at all, and just >> displays zeros, it's a 50 ohm input, compared to the 1meg 20pF Band 1 >> input. Sometimes by ramping the frequency up slowly from 100 MHz I can get >> a >> seemingly random reading. Band 3, the GHz range, doesn't work at >> all. Again, only zeros are displayed. >> >> The machine has quite a good range of self diagnosis tests. Tests are >> via the key pad. The first test checks the VCO and other stuff, and >> should display an accurate 200. MHz It displays well over, always >> in the range 253.5 and the display isn't stable, it hovers over >> several KHz. There's a tree menu to see where this issue could lie. >> One limb suggests using a known good counter on the output of the VCO. >> I did this and the output is miles high in frequency, about double, >> and unstable.
Re: [time-nuts] EIP545A 18GHz counter query
Not that it's likely to help you, but a signature analyzer uses a shift register with feedback to generate a 4 hex character "signature" from a serial data stream. It would only help if the troubleshooting tree includes a list a bad signatures for specific failures. http://www.prc68.com/I/HP5004.shtml Bob -Original Message- From: Chuck Harris Sent: Tuesday, November 27, 2012 7:45 AM To: Chris Wilson ; Discussion of precise time and frequency measurement Subject: Re: [time-nuts] EIP545A 18GHz counter query This one is usually an easy fix. The EPROMS on the controller card are using tin plated sockets, and they become tin-whisker cities. The counter will usually have enough oomph to blow any transient whiskers away if it is left running, but if it sits the whiskers will grow quickly and prevent the CPU from passing its power on self-test, and you get the "--" display. Take a high pressure air gun and blow under, around and through the EPROM sockets from all directions and angles. When you plug the board back in, it should start to work again... for a while. A more permanent fix involves removing the sockets and replacing them with gold plated sockets with machined pins. Also, on many of the 545A counters there is a design mistake on the power supply board where the wire tie that holds an electrolytic capacitor passes through the board. The holes the wire tie passes through are plated, and come through alongside of the +9V unregulated traces... bringing ground and +9V together. Drill or file the plating out of the holes to prevent spurious blowing of the mains fuse. -Chuck Harris Chris Wilson wrote: 27/11/2012 14:18 I bought a 18GHz EIP545A counter which the vendor said was working fine the day before and when on overnight soak test, and also when last used some months agao. But when he checked it on the morning of my coming over to see it he found it had developed a fault... I bought it off him cheaply, as seen, hoping it might be fixable. Here's the basic tale: It was acquired displaying just dashes. I checked the PSU voltages and found the PSU section outputting well away from the manual figures. I corrected these and checked supplies for ripple and they were all good. I then decided to remove any board that was not essential to operation. It came with a GPIB option board, so I pulled it. Luckily this did some good and a working display appeared. There were three tantalum caps on this board, as a matter of interest I pulled a leg on each and tested them, all were OK. Refitting it killed the display back to "dashes" again, so I set it aside as having an "unknown fault", and continued. I can get it to accurately display up to EXACTLY 188. MHz. Inputting 190. MHz gives zeros. It has three frequency bands. Band one works perfectly right up and well beyond its 10Hz to 100MHz range. Band two often doesn't work at all, and just diplays zeros, it's a 50 ohm input, compared to the 1meg 20pF Band 1 input. Sometimes by ramping the frequency up slowly from 100 MHz I can get a seemingly random reading. Band 3, the GHz range, doesn't work at all. Again, only zeros are displayed. The machine has quite a good range of self diagnosis tests. Tests are via the key pad. The first test checks the VCO and other stuff, and should display an accurate 200. MHz. It displays well over, always in the range 253.5 and the display isn't stable, it hovers over several KHz. There's a tree menu to see where this issue could lie. One limb suggests using a known good counter on the output of the VCO. I did this and the output is miles high in frequency, about double, and unstable. The tree menus goes on to suggest a phase lock circuitry fault. Further tests seem to depend in part upon using something called a Signature Analyser, which I have never even heard of They suggest an HP5004A, which is apparently pretty ancient. Is there a cheap way of acquiring something to do this sort of testing? I believe given a few pointers my scope, multi meter, sig gen and my other (working) Racal counter could take me further. It's a nice old thing, and I would quite like a means of counting into the higher frequencies it offers, but don't want to spend too much time or money on it. It works a damned sight more than when it first landed, which has kind of given me incentive to push a bit further, given I have a .pdf copy of the repair manual. Here's the page of the schematic I think is relevant, if it is a phase locked loop problem. This morning I realised there's a chip missing from a socket on the board in question. It's U6, a flip flop, part of the pre scaler I think? I assumed it was for some option, not fitted, but I am not so sure now. A Chinese Ebay seller is breaking one of these machines and he lists all the boards seperately, with decent photos. His board has this socket populat
Re: [time-nuts] EIP545A 18GHz counter query
This one is usually an easy fix. The EPROMS on the controller card are using tin plated sockets, and they become tin-whisker cities. The counter will usually have enough oomph to blow any transient whiskers away if it is left running, but if it sits the whiskers will grow quickly and prevent the CPU from passing its power on self-test, and you get the "--" display. Take a high pressure air gun and blow under, around and through the EPROM sockets from all directions and angles. When you plug the board back in, it should start to work again... for a while. A more permanent fix involves removing the sockets and replacing them with gold plated sockets with machined pins. Also, on many of the 545A counters there is a design mistake on the power supply board where the wire tie that holds an electrolytic capacitor passes through the board. The holes the wire tie passes through are plated, and come through alongside of the +9V unregulated traces... bringing ground and +9V together. Drill or file the plating out of the holes to prevent spurious blowing of the mains fuse. -Chuck Harris Chris Wilson wrote: 27/11/2012 14:18 I bought a 18GHz EIP545A counter which the vendor said was working fine the day before and when on overnight soak test, and also when last used some months agao. But when he checked it on the morning of my coming over to see it he found it had developed a fault... I bought it off him cheaply, as seen, hoping it might be fixable. Here's the basic tale: It was acquired displaying just dashes. I checked the PSU voltages and found the PSU section outputting well away from the manual figures. I corrected these and checked supplies for ripple and they were all good. I then decided to remove any board that was not essential to operation. It came with a GPIB option board, so I pulled it. Luckily this did some good and a working display appeared. There were three tantalum caps on this board, as a matter of interest I pulled a leg on each and tested them, all were OK. Refitting it killed the display back to "dashes" again, so I set it aside as having an "unknown fault", and continued. I can get it to accurately display up to EXACTLY 188. MHz. Inputting 190. MHz gives zeros. It has three frequency bands. Band one works perfectly right up and well beyond its 10Hz to 100MHz range. Band two often doesn't work at all, and just diplays zeros, it's a 50 ohm input, compared to the 1meg 20pF Band 1 input. Sometimes by ramping the frequency up slowly from 100 MHz I can get a seemingly random reading. Band 3, the GHz range, doesn't work at all. Again, only zeros are displayed. The machine has quite a good range of self diagnosis tests. Tests are via the key pad. The first test checks the VCO and other stuff, and should display an accurate 200. MHz. It displays well over, always in the range 253.5 and the display isn't stable, it hovers over several KHz. There's a tree menu to see where this issue could lie. One limb suggests using a known good counter on the output of the VCO. I did this and the output is miles high in frequency, about double, and unstable. The tree menus goes on to suggest a phase lock circuitry fault. Further tests seem to depend in part upon using something called a Signature Analyser, which I have never even heard of They suggest an HP5004A, which is apparently pretty ancient. Is there a cheap way of acquiring something to do this sort of testing? I believe given a few pointers my scope, multi meter, sig gen and my other (working) Racal counter could take me further. It's a nice old thing, and I would quite like a means of counting into the higher frequencies it offers, but don't want to spend too much time or money on it. It works a damned sight more than when it first landed, which has kind of given me incentive to push a bit further, given I have a .pdf copy of the repair manual. Here's the page of the schematic I think is relevant, if it is a phase locked loop problem. This morning I realised there's a chip missing from a socket on the board in question. It's U6, a flip flop, part of the pre scaler I think? I assumed it was for some option, not fitted, but I am not so sure now. A Chinese Ebay seller is breaking one of these machines and he lists all the boards seperately, with decent photos. His board has this socket populated, and looking at the schematic, (linked at the bottom of this post), I think it's probably a vital component? I am sure the seller must have known about this, but who knows... I have ordered a new chip and will fit it whwen it arrives tomorrow. Now, assuming I ever get this thing up and running fully, is there a quick and dirty way of producing a test signal in the upper limits of its range to check it out, given my Marconi sig gen stops at 1040 MHz? Perhaps using a diode to give some harmonics? Diagram of the board I believe is faulty and missing the chip is at: http://www.gatesgarth.com/phaselockloop.jpg The text for this
Re: [time-nuts] EIP545A 18GHz counter query
The first thing to do with any EIP counter is to remove and reseat all the PCBs. The card sockets they use are sometimes flaky. Simply doing this fixed most of the counters. This is especially true if they have been storfed for a while. YMMV, -John === > > > 27/11/2012 14:18 > > I bought a 18GHz EIP545A counter which the vendor said was working > fine the day before and when on overnight soak test, and also when > last used some months agao. But when he checked it on the morning of > my coming over to see it he found it had developed a fault... I bought > it off him cheaply, as seen, hoping it might be fixable. > > > Here's the basic tale: > > It was acquired displaying just dashes. I checked the PSU voltages and > found the PSU section outputting well away from the manual figures. I > corrected these and checked supplies for ripple and they were all > good. I then decided to remove any board that was not essential to > operation. It came with a GPIB option board, so I pulled it. Luckily > this did some good and a working display appeared. There were three > tantalum caps on this board, as a matter of interest I pulled a leg on > each and tested them, all were OK. Refitting it killed the display > back to "dashes" again, so I set it aside as having an "unknown > fault", and continued. I can get it to accurately display up to > EXACTLY 188. MHz. Inputting 190. MHz gives zeros. It has three > frequency bands. Band one works perfectly right up and well beyond its > 10Hz to 100MHz range. Band two often doesn't work at all, and just > diplays zeros, it's a 50 ohm input, compared to the 1meg 20pF Band 1 > input. Sometimes by ramping the frequency up slowly from 100 MHz I can get > a > seemingly random reading. Band 3, the GHz range, doesn't work at > all. Again, only zeros are displayed. > > The machine has quite a good range of self diagnosis tests. Tests are > via the key pad. The first test checks the VCO and other stuff, and > should display an accurate 200. MHz. It displays well over, always > in the range 253.5 and the display isn't stable, it hovers over > several KHz. There's a tree menu to see where this issue could lie. > One limb suggests using a known good counter on the output of the VCO. > I did this and the output is miles high in frequency, about double, > and unstable. The tree menus goes on to suggest a phase lock circuitry > fault. > > Further tests seem to depend in part upon using something called a > Signature Analyser, which I have never even heard of They suggest an > HP5004A, which is apparently pretty ancient. Is there a cheap way of > acquiring something to do this sort of testing? I believe given a few > pointers my scope, multi meter, sig gen and my other (working) Racal > counter could take me further. > > It's a nice old thing, and I would quite like a means of counting into > the higher frequencies it offers, but don't want to spend too much > time or money on it. It works a damned sight more than when it first > landed, which has kind of given me incentive to push a bit further, > given I have a .pdf copy of the repair manual. Here's the page of the > schematic I think is relevant, if it is a phase locked loop problem. > > This morning I realised there's a chip missing from a socket on the > board in question. It's U6, a flip flop, part of the pre scaler I > think? I assumed it was for some option, not fitted, but I am not so > sure now. A Chinese Ebay seller is breaking one of these machines and > he lists all the boards seperately, with decent photos. His board has > this socket populated, and looking at the schematic, (linked at the > bottom of this post), I think it's probably a vital component? I am > sure the seller must have known about this, but who knows... > > I have ordered a new chip and will fit it whwen it arrives tomorrow. > > Now, assuming I ever get this thing up and running fully, is there a > quick and dirty way of producing a test signal in the upper limits of > its range to check it out, given my Marconi sig gen stops at 1040 MHz? > Perhaps using a diode to give some harmonics? > > Diagram of the board I believe is faulty and missing the chip is at: > > http://www.gatesgarth.com/phaselockloop.jpg > > The text for this section, from the manual is at: > > http://www.gatesgarth.com/phaselocklooptext1.jpg > > and at > > http://www.gatesgarth.com/phaselocklooptext2.jpg > > Thanks for looking! > > > -- >Best Regards, >Chris Wilson. > mailto: ch...@chriswilson.tv > > > ___ > 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] EIP545A 18GHz counter query
27/11/2012 14:18 I bought a 18GHz EIP545A counter which the vendor said was working fine the day before and when on overnight soak test, and also when last used some months agao. But when he checked it on the morning of my coming over to see it he found it had developed a fault... I bought it off him cheaply, as seen, hoping it might be fixable. Here's the basic tale: It was acquired displaying just dashes. I checked the PSU voltages and found the PSU section outputting well away from the manual figures. I corrected these and checked supplies for ripple and they were all good. I then decided to remove any board that was not essential to operation. It came with a GPIB option board, so I pulled it. Luckily this did some good and a working display appeared. There were three tantalum caps on this board, as a matter of interest I pulled a leg on each and tested them, all were OK. Refitting it killed the display back to "dashes" again, so I set it aside as having an "unknown fault", and continued. I can get it to accurately display up to EXACTLY 188. MHz. Inputting 190. MHz gives zeros. It has three frequency bands. Band one works perfectly right up and well beyond its 10Hz to 100MHz range. Band two often doesn't work at all, and just diplays zeros, it's a 50 ohm input, compared to the 1meg 20pF Band 1 input. Sometimes by ramping the frequency up slowly from 100 MHz I can get a seemingly random reading. Band 3, the GHz range, doesn't work at all. Again, only zeros are displayed. The machine has quite a good range of self diagnosis tests. Tests are via the key pad. The first test checks the VCO and other stuff, and should display an accurate 200. MHz. It displays well over, always in the range 253.5 and the display isn't stable, it hovers over several KHz. There's a tree menu to see where this issue could lie. One limb suggests using a known good counter on the output of the VCO. I did this and the output is miles high in frequency, about double, and unstable. The tree menus goes on to suggest a phase lock circuitry fault. Further tests seem to depend in part upon using something called a Signature Analyser, which I have never even heard of They suggest an HP5004A, which is apparently pretty ancient. Is there a cheap way of acquiring something to do this sort of testing? I believe given a few pointers my scope, multi meter, sig gen and my other (working) Racal counter could take me further. It's a nice old thing, and I would quite like a means of counting into the higher frequencies it offers, but don't want to spend too much time or money on it. It works a damned sight more than when it first landed, which has kind of given me incentive to push a bit further, given I have a .pdf copy of the repair manual. Here's the page of the schematic I think is relevant, if it is a phase locked loop problem. This morning I realised there's a chip missing from a socket on the board in question. It's U6, a flip flop, part of the pre scaler I think? I assumed it was for some option, not fitted, but I am not so sure now. A Chinese Ebay seller is breaking one of these machines and he lists all the boards seperately, with decent photos. His board has this socket populated, and looking at the schematic, (linked at the bottom of this post), I think it's probably a vital component? I am sure the seller must have known about this, but who knows... I have ordered a new chip and will fit it whwen it arrives tomorrow. Now, assuming I ever get this thing up and running fully, is there a quick and dirty way of producing a test signal in the upper limits of its range to check it out, given my Marconi sig gen stops at 1040 MHz? Perhaps using a diode to give some harmonics? Diagram of the board I believe is faulty and missing the chip is at: http://www.gatesgarth.com/phaselockloop.jpg The text for this section, from the manual is at: http://www.gatesgarth.com/phaselocklooptext1.jpg and at http://www.gatesgarth.com/phaselocklooptext2.jpg Thanks for looking! -- Best Regards, Chris Wilson. mailto: ch...@chriswilson.tv ___ 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.
