Hi The various “sub species” of 10811’s were a test and select item done on the HP line. When they found enough to fill the need for this or that part number they stopped testing. Some of the normal parts could indeed be better than the selected versions.
We are now a *long* way past when this selection process was done. These OCXO’s have been through a lot since they came off the production line. There is no reason to believe this or that “sub part” actually is any better than a different dash number. The only answer these days is to do some shopping. Find a seller with a big pile of them and a low price. Buy a dozen and test them. If some look good, buy another dozen and test them. Eventually you will have a pile of pretty good ones. You also will have a pile of junk units. Why buy a few and test before diving in for a group? You want to be sure you aren’t buying from somebody who already has done a sort. Even if they aren’t aware of it, the group could have been sorted before they came into the picture. Is this a bit of a pain? Sure it is. It also is how people have always come up with those “poster child” versions of the 10811 you see here and there. Is this or that one a one in twenty or a one in a hundred? My guess is that even back in the day, one month it went one way and the next month it swung the other way. There is nothing particularly special about the board HP used to adapt the 10811 to do what it needed to do in the 5065A. There is a very similar part that goes into one of the Cs standards. It also can be adapted to use. If anything, the mounting bracket is the part you really need :) There are a number of old threads that pretty much all come to the conclusion “you could do better” after looking at the HP board. Building one from scratch is very do-able. Bob > On Feb 11, 2022, at 11:20 AM, Matt Huszagh <huszaghm...@gmail.com> wrote: > > Hello, > > Has anyone attempted or successfully upgraded an older HP 5065A to use a > new 10811 oscillator? > > HP created an upgrade kit for this purpose and provided a manual with full > schematics. While I would expect that upgrade kit is difficult > (impossible?) to find I imagine it might be possible to use a 10811-60109 > oscillator and recreate the other PCBs. > > Another question I had is whether the 60109 is mandatory or another 10811 > could be used in its place. The 60109 sometimes shows up in the secondary > marketplace but is harder to find than other variants. If another variant > can be used what characteristics are important to consider and which > variants might be suitable? The specifications for the 60109 are documented > so ideally a replacement would perform as well or better in ADEV and phase > noise. The 10811D/E seems to have similar specs though worse ADEV at 1s. On > the other hand, the phase noise is a bit better for the D/E. > > Matt > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send an > email to time-nuts-le...@lists.febo.com > To unsubscribe, go to and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send an email to time-nuts-le...@lists.febo.com To unsubscribe, go to and follow the instructions there.
