Here is an old post showing the schematic changes required for the 10811 oscillator modified to the 05071-60219. https://febo.com/pipermail/time-nuts_lists.febo.com/2018-January/090824.h tml Cheers, Corby

I had forgotten the details. The schematic is indeed changed because the trimmer is now in series with the varactor. That is definitely something I would do; I never approved of the trimmer being in parallel with the varactor. And the MVAM125 is one of my favorites. Definitely, I am the one to get credit or blame for this :-). It must have "just worked" as I like to say, because I never heard about it again. OTOH, I have never seen a complete 10811 schematic with this circuit. I still don't remember having to modify the PCB/flex circuit for this. I am thinking they just kluged it onto the regular one. We would want to manufacture standard 10811's from which ones intended for the 5071A could be selected. Then they would be modified with the circuit you showed. There is probably a drawing somewhere showing where to cut traces and how to install jumpers to complete the rework. Almost any section of the 5071A, beginning with the CBT is total rocket science compared to the tuning rework; and we only sold something like 10 a month in those days. I didn't know about the "wavy" ("Belleville") washers, but I totally approve. That sounds like something Len Cutler would have insisted on (if so, good for him). Rick N6RK On 8/30/2023 1:40 PM, Corby Dawson via time-nuts wrote: > Here is an old post showing the schematic changes required for the 10811 > oscillator modified to the 05071-60219. > > https://febo.com/pipermail/time-nuts_lists.febo.com/2018-January/090824.h > tml > > Cheers, > > Corby > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe send an email to time-nuts-leave@lists.febo.com >

Belleville washers are conical without waves. They are often used in aerospace optomechanics. Bruce > On 31/08/2023 12:11 NZST Richard (Rick) Karlquist via time-nuts <time-nuts@lists.febo.com> wrote: > > > I had forgotten the details. The schematic is indeed changed > because the trimmer is now in series with the varactor. That > is definitely something I would do; I never approved of the > trimmer being in parallel with the varactor. And the MVAM125 > is one of my favorites. Definitely, I am the one to get > credit or blame for this :-). It must have "just worked" > as I like to say, because I never heard about it again. > > OTOH, I have never seen a complete 10811 schematic with this > circuit. I still don't remember having to modify the PCB/flex > circuit for this. I am thinking they just kluged it onto the > regular one. We would want to manufacture standard 10811's > from which ones intended for the 5071A could be selected. Then > they would be modified with the circuit you showed. There is > probably a drawing somewhere showing where to cut traces and > how to install jumpers to complete the rework. Almost any > section of the 5071A, beginning with the CBT is total rocket > science compared to the tuning rework; and we only sold something > like 10 a month in those days. > > I didn't know about the "wavy" ("Belleville") washers, but I > totally approve. That sounds like something Len Cutler > would have insisted on (if so, good for him). > > Rick N6RK > > On 8/30/2023 1:40 PM, Corby Dawson via time-nuts wrote: > > Here is an old post showing the schematic changes required for the 10811 > > oscillator modified to the 05071-60219. > > > > https://febo.com/pipermail/time-nuts_lists.febo.com/2018-January/090824.h > > tml > > > > Cheers, > > > > Corby > > _______________________________________________ > > time-nuts mailing list -- time-nuts@lists.febo.com > > To unsubscribe send an email to time-nuts-leave@lists.febo.com > > > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe send an email to time-nuts-leave@lists.febo.com

I've got a 10811-60101 (1982 SerNo) (No A/B/D/E suffix) kicking around the lab from a scrapped HP8673B that I thought was broken when I measured it's phase noise: (Top Trace). 10 MHz Oscillators I found this: Curious as to why HP would put an "unspecified" oscillator into one of their signal generators!? (esp Phase Noise!) Jim On 2023-08-30 8:11 PM, Richard (Rick) Karlquist via time-nuts wrote: > I had forgotten the details.  The schematic is indeed changed > because the trimmer is now in series with the varactor.  That > is definitely something I would do; I never approved of the > trimmer being in parallel with the varactor.  And the MVAM125 > is one of my favorites.  Definitely, I am the one to get > credit or blame for this :-).  It must have "just worked" > as I like to say, because I never heard about it again. > > OTOH, I have never seen a complete 10811 schematic with this > circuit.  I still don't remember having to modify the PCB/flex > circuit for this.  I am thinking they just kluged it onto the > regular one.  We would want to manufacture standard 10811's > from which ones intended for the 5071A could be selected.  Then > they would be modified with the circuit you showed.  There is > probably a drawing somewhere showing where to cut traces and > how to install jumpers to complete the rework.  Almost any > section of the 5071A, beginning with the CBT is total rocket > science compared to the tuning rework; and we only sold something > like 10 a month in those days. > > I didn't know about the "wavy" ("Belleville") washers, but I > totally approve.  That sounds like something Len Cutler > would have insisted on (if so, good for him). > > Rick N6RK > > On 8/30/2023 1:40 PM, Corby Dawson via time-nuts wrote: >> Here is an old post showing the schematic changes required for the 10811 >> oscillator modified to the 05071-60219. >> >> https://febo.com/pipermail/time-nuts_lists.febo.com/2018-January/090824.h >> >> tml >> >> Cheers, >> >> Corby >> _______________________________________________ >> time-nuts mailing list -- time-nuts@lists.febo.com >> To unsubscribe send an email to time-nuts-leave@lists.febo.com >> > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe send an email to time-nuts-leave@lists.febo.com -- Jim Muehlberg Senior Engineer National Radio Astronomy Observatory ngVLA Local Oscillator Lead 1180 Boxwood Estates Rd B-111 Charlottesville, VA 22903-4602 P 434.296.0270 C 434.422.2017

One day, I'll figure out the attachment protocol on this list!... PN plot and manual section attached, I hope. Jim On 2023-08-31 10:13 AM, Jim Muehlberg via time-nuts wrote: > I've got a 10811-60101 (1982 SerNo) (No A/B/D/E suffix) kicking around > the lab from a scrapped HP8673B that I thought was broken when I > measured it's phase noise: (Top Trace). > > 10 MHz Oscillators > > I found this: > > > Curious as to why HP would put an "unspecified" oscillator into one of > their signal generators!? (esp Phase Noise!) > > Jim > > On 2023-08-30 8:11 PM, Richard (Rick) Karlquist via time-nuts wrote: >> I had forgotten the details.  The schematic is indeed changed >> because the trimmer is now in series with the varactor.  That >> is definitely something I would do; I never approved of the >> trimmer being in parallel with the varactor.  And the MVAM125 >> is one of my favorites.  Definitely, I am the one to get >> credit or blame for this :-).  It must have "just worked" >> as I like to say, because I never heard about it again. >> >> OTOH, I have never seen a complete 10811 schematic with this >> circuit.  I still don't remember having to modify the PCB/flex >> circuit for this.  I am thinking they just kluged it onto the >> regular one.  We would want to manufacture standard 10811's >> from which ones intended for the 5071A could be selected.  Then >> they would be modified with the circuit you showed.  There is >> probably a drawing somewhere showing where to cut traces and >> how to install jumpers to complete the rework.  Almost any >> section of the 5071A, beginning with the CBT is total rocket >> science compared to the tuning rework; and we only sold something >> like 10 a month in those days. >> >> I didn't know about the "wavy" ("Belleville") washers, but I >> totally approve.  That sounds like something Len Cutler >> would have insisted on (if so, good for him). >> >> Rick N6RK >> >> On 8/30/2023 1:40 PM, Corby Dawson via time-nuts wrote: >>> Here is an old post showing the schematic changes required for the >>> 10811 >>> oscillator modified to the 05071-60219. >>> >>> https://febo.com/pipermail/time-nuts_lists.febo.com/2018-January/090824.h >>> >>> tml >>> >>> Cheers, >>> >>> Corby >>> _______________________________________________ >>> time-nuts mailing list -- time-nuts@lists.febo.com >>> To unsubscribe send an email to time-nuts-leave@lists.febo.com >>> >> _______________________________________________ >> time-nuts mailing list -- time-nuts@lists.febo.com >> To unsubscribe send an email to time-nuts-leave@lists.febo.com -- Jim Muehlberg Senior Engineer National Radio Astronomy Observatory ngVLA Local Oscillator Lead 1180 Boxwood Estates Rd B-111 Charlottesville, VA 22903-4602 P 434.296.0270 C 434.422.2017

Hi The 10811 on that plot would go in the “broken” pile if I was doing a sort. I suspect there is something wrong with it internally. Just what …. who knows. Bob > On Sep 1, 2023, at 9:19 AM, Jim Muehlberg via time-nuts <time-nuts@lists.febo.com> wrote: > > One day, I'll figure out the attachment protocol on this list!... > > PN plot and manual section attached, I hope. > > Jim > > On 2023-08-31 10:13 AM, Jim Muehlberg via time-nuts wrote: >> I've got a 10811-60101 (1982 SerNo) (No A/B/D/E suffix) kicking around the lab from a scrapped HP8673B that I thought was broken when I measured it's phase noise: (Top Trace). >> >> 10 MHz Oscillators >> >> I found this: >> >> >> Curious as to why HP would put an "unspecified" oscillator into one of their signal generators!? (esp Phase Noise!) >> >> Jim >> >> On 2023-08-30 8:11 PM, Richard (Rick) Karlquist via time-nuts wrote: >>> I had forgotten the details. The schematic is indeed changed >>> because the trimmer is now in series with the varactor. That >>> is definitely something I would do; I never approved of the >>> trimmer being in parallel with the varactor. And the MVAM125 >>> is one of my favorites. Definitely, I am the one to get >>> credit or blame for this :-). It must have "just worked" >>> as I like to say, because I never heard about it again. >>> >>> OTOH, I have never seen a complete 10811 schematic with this >>> circuit. I still don't remember having to modify the PCB/flex >>> circuit for this. I am thinking they just kluged it onto the >>> regular one. We would want to manufacture standard 10811's >>> from which ones intended for the 5071A could be selected. Then >>> they would be modified with the circuit you showed. There is >>> probably a drawing somewhere showing where to cut traces and >>> how to install jumpers to complete the rework. Almost any >>> section of the 5071A, beginning with the CBT is total rocket >>> science compared to the tuning rework; and we only sold something >>> like 10 a month in those days. >>> >>> I didn't know about the "wavy" ("Belleville") washers, but I >>> totally approve. That sounds like something Len Cutler >>> would have insisted on (if so, good for him). >>> >>> Rick N6RK >>> >>> On 8/30/2023 1:40 PM, Corby Dawson via time-nuts wrote: >>>> Here is an old post showing the schematic changes required for the 10811 >>>> oscillator modified to the 05071-60219. >>>> >>>> https://febo.com/pipermail/time-nuts_lists.febo.com/2018-January/090824.h >>>> tml >>>> >>>> Cheers, >>>> >>>> Corby >>>> _______________________________________________ >>>> time-nuts mailing list -- time-nuts@lists.febo.com >>>> To unsubscribe send an email to time-nuts-leave@lists.febo.com >>>> >>> _______________________________________________ >>> time-nuts mailing list -- time-nuts@lists.febo.com >>> To unsubscribe send an email to time-nuts-leave@lists.febo.com > -- > > Jim Muehlberg > Senior Engineer > > National Radio Astronomy Observatory > ngVLA Local Oscillator Lead > > 1180 Boxwood Estates Rd B-111 > Charlottesville, VA 22903-4602 > P 434.296.0270 > C 434.422.2017 > <10 MHz Oscillators1.jpg><10811-60101.jpg>_______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe send an email to time-nuts-leave@lists.febo.com