Re: [time-nuts] HP 5065 Meter readings after restoration and adjustments: 2nd Harmonic Problems ?
Hi , these jumps when tapping is normal when the HP5065A is restored to the life ater a long storage time, they disappears after a long warmup (weeks). Luciano Da "time-nuts" time-nuts-boun...@febo.com A "Ulf Kylenfall" ulf_...@yahoo.com,"Discussion of precise time and frequency measurement" time-nuts@febo.com Cc Data Fri, 08 Sep 2017 08:49:12 +0000 Oggetto Re: [time-nuts] HP 5065 Meter readings after restoration and adjustments: 2nd Harmonic Problems ? In message <125529892.249004.1504854237...@mail.yahoo.com>, Ulf Kylenfall via time-nuts writes: >The meter is not stable and the needle is somewhatnervous. When tapping the instrument with a smallscrewdriver, this value jumps up and down. If the jumps are always the same place on the scale, it is probably a mechanical issue in the meter, if it is all over the scale it could be the rotary switch which selects what the meter shows. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] HP 5065 Meter readings after restoration and adjustments: 2nd Harmonic Problems ? (II)
In message <881182040.5268197.1504868987...@mail.yahoo.com>, Ulf Kylenfall via time-nuts writes: > >2nd Harmonic level has gone down from 18 to 14 in a few hours.Needle is >nervous in the way that it wiggles about one needle-widthin a random but slow >pace. >All other readings are stable. >Rotating the knob back and forth restores the previous readings. >I am considering a fault in the 137 MHz circuitry. It can also be the synth which bounces up and down in frequency if the delay-line has drifted. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] HP 5065 Meter readings after restoration and adjustments: 2nd Harmonic Problems ? (II)
2nd Harmonic level has gone down from 18 to 14 in a few hours.Needle is nervous in the way that it wiggles about one needle-widthin a random but slow pace. All other readings are stable. Rotating the knob back and forth restores the previous readings. I am considering a fault in the 137 MHz circuitry. /Ulf ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] HP 5065 Meter readings after restoration and adjustments: 2nd Harmonic Problems ?
> My intention is to leave the instrument on for severalweeks in order to see > if it is stable. Right nowmy concern is wether the 2nd harmonic > readingindicates a wear out of the photo cell. > When repairing the RFV Cavity, all components weretaken out and carefully > examined. There wereno dimmed or darkened glass surfaces > whatsoever.Apart from repairing the TX heater, the only other thingwas > replacing the 1K something resistor in the TXassembly. You've checked the ESR of all the axial electrolytic caps, right? If not, it's quite unlikely that they're all good. -- john, KE5FX Miles Design LLC ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] HP 5065 Meter readings after restoration and adjustments: 2nd Harmonic Problems ?
In message <125529892.249004.1504854237...@mail.yahoo.com>, Ulf Kylenfall via time-nuts writes: >The meter is not stable and the needle is somewhatnervous. When tapping the >instrument with a smallscrewdriver, this value jumps up and down. If the jumps are always the same place on the scale, it is probably a mechanical issue in the meter, if it is all over the scale it could be the rotary switch which selects what the meter shows. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] HP 5065 Meter readings after restoration and adjustments: 2nd Harmonic Problems ?
Having repaired an old 5065 with help from documentson the KO4BB and this list, I took it to my workat Onsala Space Observatory where we have two H-Masers in order to fine tune it. Initially, the meter readings were close to those listed insidethe protective lid, dated 1987 when the instrument was decomissioned. Supply = 40Lamp Oven = 24Cell Oven = 28Osc Oven = 48Photo I = 305 MHz = 38Control = 0 (After adjustments)Error = 02nd harmonic 18 (was 30 initially)1MHz/100 kHz = 40 Because it is an early instrument, it did not featurethe thermoelectric device that is recommended forformatting the PhotoCell I used a hair dryer to format itfollowing the advice of Corby Dawson. The 2nd Harmonicvalue was initially at 30, but now it has dropped to 18. "ON"-time is now ~ 24 hours. The meter is not stable and the needle is somewhatnervous. When tapping the instrument with a smallscrewdriver, this value jumps up and down. The instrument is still locked, and after adjusting theSynthesizer & Magnetic field, comparing the 5MHzoutput to that of the H-Maser indicates a phase shiftchange of approx. 0.1 degree in 30 seconds. I did the alignment yesterday, and 12 hours later the phaseshift "velocity" has not changed. I also tooka phase noise plot using a Keysight PXA but I do notknow if the plot is a "true" one. There seems to bea pedestal within 10 Hz of the 5 MHz signal after whichthe PN drops significantly. No power line bumpsor other spurii is visible. My intention is to leave the instrument on for severalweeks in order to see if it is stable. Right nowmy concern is wether the 2nd harmonic readingindicates a wear out of the photo cell. When repairing the RFV Cavity, all components weretaken out and carefully examined. There wereno dimmed or darkened glass surfaces whatsoever.Apart from repairing the TX heater, the only other thingwas replacing the 1K something resistor in the TXassembly. Comments invited. Ulf KylenfallSM6GXV ___ 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.
