[time-nuts] Re: HP 10811-60111 Oscillators

[Matt Huszagh]

Bob Camp via time-nuts <time-nuts at lists.febo.com> writes:

> There’s a seller on eBay ( besttestus ) who comes up with batches of 10811’s from who
> knows where. Some are still attached to option boards for instruments. They just sold out
> of the latest batch of about 200 or so. I’d guess they will get some back in eventually.
> Asking price is typically right around $50 or so (with free shipping). They take offers so
> you can indeed get them to sell you 10 at a whack for around $42 each.
>
> Based on testing more than a few of them, there will be a couple that have significant
> issues ( < 5%). There will be some that are in spec, but not by as much as when they
> left the factory ( maybe another 5 %). The rest split into “pretty good” and “really good”.
>
> The fact that the really good ones are still in the group suggests that these are indeed
> NOS or something like that. A lot of batches you see have the best of the best pulled out
> and you are just buying “the rest”. I’d guess that Fair is in the same mode, you get the
> whole lot and can sort time as you wish.
>
> Just how many show up in the sub 6x10^-13 ADEV range varies a bit by lot. To me,
> anything that’s in the parts in 10^-13 counts as very good. How many would improve
> if you burned them in for six months or so, who knows….
>
> Bottom line: You probably do better buying closer to the source of the surplus in a
> case like this.

I went this route too. The one thing I'll say is be sure to test them
for at least basic functionality on arrival. besttestus says they test
them, but they don't. I received 1 of 3 with some part of the oscillator
circuit dead (no output). Of course, the seller is happy to reimburse or
send another in this case.

Matt