[Heathkit] DX-40 question

[Jack Antonio]

I'm working on the same DX-40 I've had since my Novice
days 50 some years ago.

Cleaning, tightening screws, checking solder joints
new 6146, tune up.

And the end result is a transmitter that works good
with one exception.

It is a little squirrely on 40 meters, with 40 meter
crystals. The "band-aid" is to back the oscillator coil all the
way out, and keep grid drive below 2mA.

By squirrely, I mean that it has a tendency to take off
on its own without a crystal in the socket, jumpy tuning,
sluggish crystal activity that depends on both tuning and
the position of the meter switch. Again, this is only
on 40, with 40 meter crystals. All other bands work just fine.

The question is, wasn't this documented somewhere? I seem
to recall this, but a search of the ARRL QST archive, and
a quick look through my 73 magazines, didn't reveal anything.

Just wondering if anyone else has heard of this, or know of
any writeups about it.

Thing is, I don't remember this issue from 50 years ago, but
then also, I never had good luck with this transmitter on 40.
Always had good results on 80 and 15 though.

Thanks

Jack Antonio WA7DIA/4