If I had to guess from the photos, I would try the resistors on standoffs next to the 20K pot at the bottom of the photo OSC_02. I assume the pot is the frequency adjustment.
On Thu, Oct 25, 2018 at 8:38 PM paul swed <[email protected]> wrote: > Hello to the group. > Ulf looks like a lot of people are trying to help. > Earlier in the thread it was mentioned that there often is a tuning cap of > some fixed value. > I have actually slightly adjusted those to fix as an example a HP 10811. > Typically its a single cap. > But it can't hurt to try changing it if you can figure out the cap. > Regards > Paul > WB8TSL > > On Thu, Oct 25, 2018 at 7:14 PM Bob kb8tq <[email protected]> wrote: > > > 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 <[email protected]> > > 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 <[email protected]> > 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 <[email protected]> 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 < > > >>> [email protected]> 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 -- [email protected] > > >>>> To unsubscribe, go to > > >>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > > >>>> and follow the instructions there. > > >>> > > >>> > > >>> _______________________________________________ > > >>> time-nuts mailing list -- [email protected] > > >>> To unsubscribe, go to > > >>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > > >>> and follow the instructions there. > > >>> > > >> _______________________________________________ > > >> time-nuts mailing list -- [email protected] > > >> To unsubscribe, go to > > >> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > > >> and follow the instructions there. > > >> > > > _______________________________________________ > > > time-nuts mailing list -- [email protected] > > > To unsubscribe, go to > > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > > > and follow the instructions there. > > > > > > _______________________________________________ > > time-nuts mailing list -- [email protected] > > To unsubscribe, go to > > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > > and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. > -- --Jim Harman _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
