[time-nuts] Dead 5065A - Some comments - Some questions...

[Poul-Henning Kamp]

--------
Ulf Kylenfall via time-nuts writes:

> I checked the A1 syntesizer unit which did
> provide correct output frequencies but
> they were not as stable [...]

> I have two of these synthesizers, but they are
> both the 1st edition using TO packaged
> IC's that are unobtanium. One of my manuals
> shows a more modern unit with plastic DIP's.
> Some signetics and a one-shot that is unidentifiable.

I had one of those one-shot's become unstable.

I replaced the entire digital divider-chain with the PWM peripheral
in a LPC810 8-pin DIP ARM chip.

Pretty much any microcontroller with a decent PWM can do the job,
which is to output a 10µs pulse evern N cycles of a 5MHz clock
signal.

I hardcoded the divisor ratio, but one wants to, 16 GPIOs on
the microcontroller could read BCD thumbwheels.

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