> Are you saying that some HP-xxxx counters/timers/whatever would ship > with an 10811A, whereas another instrument with the same model number > and options ordered would ship with a different oscillator?
It's hard to say. I've seen mil-spec versions of the 5238A shipped with a EGG 10811 clone. It is not impossible that HP would ship whatever met spec or better in a counter. But more importantly the other reason it's hard to know is that the 10544 and 10811 are 20 to 30 years old now. So when you get an instrument with an OCXO there's no telling what is original and what has been board swapped over the years. In any sort of commerical or university lab, you have to expect that OCXO or any other removable parts are swapped around as needed. Also if an eBay seller has spare parts and needs to sell a functional counter, he will install whatever works. Buying gear for 10% to 1% of original cost on eBay is wonderful; but one of the few tradeoffs is certainty. You can't know, and often the seller can't know, just how easy or how hard a life a piece of electronics has had in the decades before. Nor can you know if all the parts inside a piece of gear are original. So we sort of take what we can get and measure it to see what we got. /tvb _______________________________________________ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
