I wouldn't worry much about the band setting crystals,
you only have a string dial with that rig, so you need
to spot with an accurate receiver if you get near the band edges anyway.

The important crystals are the USB and LSB carrier oscillator
crystals. If they are off frequency, your voice will either
sound thin or bassy.

There is an easy mod to almost elliminate the resting current
of the 6DQ5 during HX-50 standby periods.
The mod appeared in an early-sixties CQ magazine,
and is very worthwhile to reduce heat in the cabinet.

If you'd like, I'll send the info to you directly.

73,
Ed Knobloch

Ed,

Please send me the mod. I found some modifications had been done to the
bias circuit. It would be great to verify them.

THANKS!
Paul

paulREMOVE at REMOVEppinyot dot REMOVEcom