[time-nuts] Tracor 527A and 10MHz reference input

[David C. Partridge]

A friend says his Tracor 527A works fine with a 10MHz Ref input even though
it doesn't have the divide by 2 circuit from the addendum to the 527E manual
applied.

I'm puzzled by this - I can't quite see how the reference input circuit can
produce a 5MHz output when fed with 10MHz (unless his reference source has a
large 5MHz sub-harmonic).

Am I missing something here?

On a related note, the schematic for the divide by 2 circuit in the front of
the 527E manual shows a 4R7 resistor from the base of the 2N3904 to ground -
this just feels all wrong!!  Has anyone built this and did they change the
resistor to (e.g. 47R or 4K7)?

Thanks
Dave