What impedance loading is the output specified for? 1M or 50R. Could I suggest using a distribution amp?
Dave -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Nick Foster Sent: 15 January 2010 19:53 To: [email protected] Subject: [time-nuts] HP 10544A with dodgy output? Hi all, I've just built a GPS-disciplined oscillator built around a 10544A, somewhat in the style of the Brooks Shera unit, just to use around the shack. Problem is, now that it's wired up, I notice the output is heavily distorted. It's clipped on the negative side of the waveform, like an emitter follower without enough headroom. The more I load the oscillator output, the heavier the clipping. When I load the oscillator output with 1000 ohms, spec for this unit, almost 30% of the waveform is clipped on the negative side. If I don't load it at all and just put a probe on the output, it looks OK, but still some flattening of the bottom half of the waveform. I've got it wired up according to the datasheet, with +12V on the oscillator and +20V on the heater. The grounds for the oscillator/amplifier, oven controller, heater, and output are all tied together. I know these are old units, and I'm wondering if this is a problem (for instance in the output emitter follower amp) that others know about, before I tear into it looking for a solution. Thanks for your time, Nick _________________________________________________________________ Your E-mail and More On-the-Go. Get Windows Live Hotmail Free. http://clk.atdmt.com/GBL/go/196390709/direct/01/ _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
