geoffrey pike

Back to DC matters at 10.368 GHz, i finally fitted my OZ5N auto pll and this is what happened.
Well it really didn't want to lock up at all, i changed the 82 p at the crystal to 56p. I gave everything some time to warm up and although
the blue LED flashed at 1 sec intervals it just wasn't for locking up.I adjusted the coil for a resting frequency about 200 Hz high and tried again and it locked up OK. I measured the control voltage at 1.04v and readjusted for 1.7v as i thought that this would be better and sure enough when i tried it all again the lock up was within 2 seconds.
So from a cold DB6NT it takes about 2 secs to lock but when the 10 MHz ref is removed and the xtal is up to temp it takes about 10 secs to lock.
I then put it all back together again and got my signal source fro 10.368200 GHz going and tuned in spot on 144.200 on the 290 and it just sits there rock steady T9. So that only leaves azimuth control of the dish as an unknown !.
I measured the crystal frequency on the collector of the first tripler via a 22p cap

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