[Premium-Rx] WJ-340A manual

[David Atkins]

Hello to the list.

I managed to obtain a WJ-340A-6 vlf receiver, and I'm struggling to make the
best of it. Does anyone know where I can obtain a manual, handbook,
schematic, or even an info-sheet for this receiver series?

It seems very sensitive, but there are a couple of items I'd like to tackle.
It takes up to four hours for the L.O. to settle down. I run my RA1792 with
an external frequency standard -- even without, it is rock-solid in
comparison with the 340A. Has anyone tackled this on a 340A? Is this warm-up
time normal for them?
The tuning is very coarse; even the "Fine-tune" is too coarse for creeping
up on a beacon signal. Am I right in thinking WJ used a varicap, here? Would
a multi-turn pot improve things?
There are some rear-apron sockets that I would like to understand the uses
of. Can anyone help?
And finally (this time), what is the "log" position on the mode-switch for?

I'd really like to buy a manual ...

Best Wishes

David Atkins, G8XBZ
IO91sq