Gentlemen.  I have salvaged a manual for a Varian R-20 Rubidium Frequency Standard.   It was left when my employer borrowed such a unit when performing the first cross-atlantic VLBI Experiments some time in the late 70's. The unit must have been returned to its owner but they forgot to include the manual...   It is in excellent shape.   Are there any such units still in operation? Is there a need for it? The thickness of the papers is about 1 inch. Most pages are easy enough to scan but the last 1/3rd is fold-out schematics for which I have no appropriate way to scan.   Best Regards   Ulf Kylenfall SM6GXV

Nice find. Original manuals are sometimes harder to find than original equipment. In the case of the Varian R20 there is a clean copy on fellow time-nut Didier's website: http://www.ko4bb.com/manuals Search for Varian or R20. The 128 page file is: Varian_R20_Rubidium_Frequency_Standard_Service_Manual_1966.pdf See how your hardcopy compares with that PDF. FYI, there is a nice history of Rb standards here: "A History of the Rubidium Frequency Standard" http://www.wriley.com/A%20History%20of%20the%20Rubidium%20Frequency%20Standard.pdf /tvb On 12/6/2020 3:24 AM, Ulf Kylenfall via time-nuts wrote: > Gentlemen. > I have salvaged a manual for a Varian R-20 Rubidium Frequency Standard. > > It was left when my employer borrowed such a unit when > performing the first cross-atlantic VLBI Experiments > some time in the late 70's. The unit must have been returned to its > owner but they forgot to include the manual... > > It is in excellent shape. > > Are there any such units still in operation? > Is there a need for it? The thickness of the papers > is about 1 inch. Most pages are easy enough to scan but the > last 1/3rd is fold-out schematics for which I have no > appropriate way to scan. > > Best Regards > > Ulf Kylenfall > SM6GXV > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there.

Ulf- I have the R-20 unit and no manual. I'd be very interested in it or scans of it please! Best Regards, Bill On Sun, Dec 6, 2020, 5:59 AM Ulf Kylenfall via time-nuts < time-nuts@lists.febo.com> wrote: > > Gentlemen. > I have salvaged a manual for a Varian R-20 Rubidium Frequency Standard. > > It was left when my employer borrowed such a unit when > performing the first cross-atlantic VLBI Experiments > some time in the late 70's. The unit must have been returned to its > owner but they forgot to include the manual... > > It is in excellent shape. > > Are there any such units still in operation? > Is there a need for it? The thickness of the papers > is about 1 inch. Most pages are easy enough to scan but the > last 1/3rd is fold-out schematics for which I have no > appropriate way to scan. > > Best Regards > > Ulf Kylenfall > SM6GXV > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. >

The scans look good on the website. Thanks for the lead Tom. I still like collecting the original manuals for devices I have. You're right sometimes harder to find than the gear is! Bill On Sun, Dec 6, 2020, 6:10 AM Tom Van Baak <tvb@leapsecond.com> wrote: > Nice find. Original manuals are sometimes harder to find than original > equipment. In the case of the Varian R20 there is a clean copy on fellow > time-nut Didier's website: > > http://www.ko4bb.com/manuals > > Search for Varian or R20. The 128 page file is: > > Varian_R20_Rubidium_Frequency_Standard_Service_Manual_1966.pdf > > See how your hardcopy compares with that PDF. FYI, there is a nice > history of Rb standards here: > > "A History of the Rubidium Frequency Standard" > > http://www.wriley.com/A%20History%20of%20the%20Rubidium%20Frequency%20Standard.pdf > > /tvb > > > On 12/6/2020 3:24 AM, Ulf Kylenfall via time-nuts wrote: > > Gentlemen. > > I have salvaged a manual for a Varian R-20 Rubidium Frequency Standard. > > > > It was left when my employer borrowed such a unit when > > performing the first cross-atlantic VLBI Experiments > > some time in the late 70's. The unit must have been returned to its > > owner but they forgot to include the manual... > > > > It is in excellent shape. > > > > Are there any such units still in operation? > > Is there a need for it? The thickness of the papers > > is about 1 inch. Most pages are easy enough to scan but the > > last 1/3rd is fold-out schematics for which I have no > > appropriate way to scan. > > > > Best Regards > > > > Ulf Kylenfall > > SM6GXV > > _______________________________________________ > > time-nuts mailing list -- time-nuts@lists.febo.com > > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > > and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. >