You found the secret. There is no RF wiring to the crystal. The oscillator frequency is determined elsewhere, with a free running multivibrator that is approximately on the right frequency. All this talk about precision is baloney; the circuit is stable enough to fool even the experts. And it's not even April 1 yet. Bob On Tuesday, December 12, 2017, 9:32:44 AM PST, Ed Palmer <ed_pal...@sasktel.net> wrote: It sounds like yours is different from my 8601. How old is yours? From the label inside it looks like mine is from 1983.
Internal pictures are here: http://s701.photobucket.com/user/edpalmer42/library/Oscilloquartz%208601%20Oscillator If you click on 'view as story' you'll see some comments that I added to the pictures. Ed On 2017-12-12 11:00 AM, <ulf_...@yahoo.com> wrote: > Emailed Oscilloquartz that now has another name: Advaoptical... This in my > capacity as aresearch engineer at Onsala Space Observatory.And the oscillator > is at my work bench. Nothingprivate/hobby about this. > The answer was that since we do not have a service agreement,they would not > disclose any information. > (Compare this with Keysight who has a free downlad area for oldmanuals. IMO > the Keysight approach benifits their businessin the long term). > So... > I went along and started to dissassemble the 8600-3. > The outer case was easy. Inside is a PCB with RF buffersand temperature > regulation circuitry. > Then there is a thermo bottle with the ovenized oscillator.This unit is > connected to the PCB using two flex cables. > The oscillator unit can simply be extracted from thebottle using an Metric 3 > mm screw lightly screwed inone of the holes in the oscillator assembly. > The assembly can be accessed by carfully unscrewingthe flex-cable end from > the other mechanics. No needto touch the three small screws at the lid. > Now it is starting to get intersting. I have not foundthe RF wiring into the > crystal. The PCB in this unitseems to deal only with temperature > regulation.Possibly, the RF is routed together with some heaterwinding. > Or the crystal and the oscillator parts is sealedin such a way that there > will be no wayto dissassemble it. There are several thermistorsglued inside > to various parts of the oscillator/ovenassembly. That will make any further > attemptsdifficult as the connecting wires are thin and delicateif they needs > to be unsoldered. > The construction is a nice piece of engineering.I'll give them that. > Right now, I cannot see any typical oscillatorcircuitry (pF, nH, RF > transistors) etc. > I think I'll contemplate on the next movefor a day or so... > > Ulf Kylenfall > > _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.