[time-nuts] Wenzel VHF PLO Oscillators Off Frequency

John Miles john at miles.io
Sun Nov 12 20:38:03 EST 2017

> Yes, exactly those. With no input, would they be expected to be 4 kHz off?
> The spec for the standard part wants the input to be within 1e-7. I would
> not expect them to be so far off free running.

That does seem like a lot.  I'd expect a few hundred Hz of error at the most.
> I saw 13 MHz on the 500-14273 and stayed away from those.
> Do you know of any part numbers that use 10 MHz in? Wenzel would not tell
> me the exact specs of the 500 series parts available on ebay and only sent
> me the specs for the standard 501-14057 that takes 10 MHz.

Most of the 100 and 200 MHz bricks I've seen work with either 5 or 10 MHz .  I don't know if I've seen any 80 MHz units that do.  All of the ones I've bought on eBay have been from the customer-proprietary 500- series with unusual input frequencies.

> Do you know what the pll lock output does when the input frequency is off?
> These toggle high for any frequencies I have put in.

Not offhand.  If there's a PFD inside it should be easy to zero in on the right frequency, but if there's only a phase detector you may need to set up a sweep and watch the tuning-voltage output on a scope.  I don't remember it taking very long to find the correct input frequencies for the ones I bought, though.   

-- john, KE5FX
Miles Design LLC

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