Hi One fairly real possibility - it can’t be repaired. The tuning range of a BVA based oscillator is pretty small. It may be that the crystal has simply aged further than it can be tuned.
Assuming the device is still operating properly, there are a lot of uses for a working “1Hz off” 5 MHz OCXO ….. Bob > On Oct 25, 2018, at 3:38 PM, Mark Goldberg <marklgoldb...@gmail.com> wrote: > > I agree they likely won't provide a schematic and will want it back for > repair. If it is a proprietary design for someone, they may not even repair > it for you and certainly won't give you any info. I was at least able to > get a little info from Wenzel about a similar oscillator I was looking at > and they gave me hints about what the one I had was not, basically not > telling me info but keeping me from heading down the wrong path. If you ask > nicely via email and are understanding about their situation with > proprietary products, maybe they will be of some help. > > I have reverse engineered a couple of oscillators. You don't have to > reverse engineer the whole thing, just the frequency adjustment section. I > don't know anything about this oscillator but you can determine what the > available adjustment is, a pot or a trimmer cap. If it is a pot, is there > another resistor that sets the course adjustment? If it is a trimmer cap, > there is usually a parallel cap that sets the course adjustment. Possibly > those could be replaced with different values to get the adjustment range > back. Worth a try. > > If you can look at the circuit around the crystal, you likely can determine > what the oscillator topology is. > > Can you tell if the oven is working? Typically it will draw more current on > startup and then reduce the current draw after a while when it gets to > temperature. I've found broken heater wires before. > > Regards, > > Mark > > > On Thu, Oct 25, 2018 at 11:26 AM paul swed <paulsw...@gmail.com> wrote: > >> Ulf >> I have no details. But perhaps off list we could reverse engineer it. >> Simply a suggestion. Especially since you have it open. >> Regards >> Paul >> WB8TSL >> >> On Thu, Oct 25, 2018 at 2:15 PM Bob kb8tq <kb...@n1k.org> wrote: >> >>> Hi >>> >>> Even with an “account”, most oscillator companies will not supply >> internal >>> details on their product. That’s in part >>> to protect their IP. It also reflects the complexity of tracing back to >>> exactly what doc’s apply to an older unit. The >>> normal drill is for you to send it back and they take a look at it. They >>> then quote a repair charge and you either >>> go ahead with it or have them send it back. >>> >>> Bob >>> >>>> On Oct 25, 2018, at 1:56 PM, Ulf Kylenfall via time-nuts < >>> time-nuts@lists.febo.com> wrote: >>>> >>>> >>>> Many monts ago I approached the list regarding an Oscilloquartz >>> 8600-3(945.860.011.03 s/n 422) 5 MHz Ovenized Crystal Oscillator. It had >>> aged and was 1 Hz off and couldnot be braught back to 5.000.000 MHz. >>>> Since I did not have "an account" with Oscilloquartz or what they are >>> calledtoday, I was not able to get any help from them. >>>> There was one answer off the list from someone who could possibly >>> helpbut that person either forgot or did not have any relevant >>> informationto share. >>>> A box with the dismantled unit has been laying on my shelf for months >>> and I am therefore asking again. If there is no information about >> thisunit >>> available I will scrap it. I do not know of any other forumto ask. >>>> Best Regards >>>> >>>> Ulf KylenfallSM6GXV >>>> >>>> _______________________________________________ >>>> 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. >>> >> _______________________________________________ >> 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. _______________________________________________ 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.