Hi First step would be to lift the +22 feed wire and see if a current meter shows any current drain into the doubler box. The 7818 would suggest that you have no current, but it may just be well heat sunk. If there's no current into the box, it's time to open it up.
Bob On Apr 3, 2013, at 2:53 PM, Robert Darby <bobda...@triad.rr.com> wrote: > I purchased an FTS 1050 recently and after a cursory inspection of the > interior powered it up to see if it's functional. > > This particular unit is a bit odd; it has the optional battery back-up, no > PPS, and instead of the usual 1Mhz, 5Mhz, 10Mhz it has four 10Mhz outputs > with tnc female connectors. > > The tnc connectors are a bit of a bother but I found that the scope probe > sleeve that fits a bnc also fits into a tnc so I'm able to view the outputs. > They are not pretty, lots of hash, particularly at the zero crossings and > only about 15 to 20mV rms. That's the case for all four. > > The oscillator is an FTS 1000B-503 which is supposed to have four buffered > outputs at 5MHz; two at 1.0 V rms and two at 0.5 V rms. Two outputs each > drive a pair of frequency doublers that thus provide the four 10Mhz outputs. > I got a connector on one of the spare outputs to see if the problem might lie > in the oscillator. What I see there is a very stable clean sine wave at 5MHz > at about 660mV rms so I'm assuming the 1000B is not my problem. > > The doublers are housed in a tidy box adjacent to the oscillator with 22V and > ground, two 5MHz inputs and four 10MHz outputs all in the top cover. There > is a stone cold 7818 in a TO-3 metal can mounted on one side of the box but > no external connections other than those previously noted. It seems to me my > problem must lie in this area and, since all four circuits are similarly > affected, is probably related to the power supply housed therein. > > This is probably obvious to all of you but I'm a toolmaker by trade so this > is all new to me and second opinions will not hurt my feelings. Also does > anyone have any experience inside of the doubler box or a schematic of the > standard (or any other version) doubler/divider for these things? > > Thanks for any insight anyone can offer. > > Bob Darby > _______________________________________________ > 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.