In article , "Ron Price"
wrote:

The equipment is an old Lab-Craft UHF Signal Strength Meter probably from
the 60's or 70's.
I have partly dismantled it and plan on using the chassis and psu to build a
one or two valve QRP CW TX for 80-m so I wanted a rough idea of what sort of
current I could pull from the rectifier. The previous valve line-up was
PC86, PC88, EF184(x2),6AL5,OA2.
I have an old data book and this lista a few rectifiers starting with FC but
not the one I want!

Ron-

If you plan to use the existing power supply, then the rectifier is most
likely capable of handling as much current as the the transformer can
deliver. If you don't want to trust it, one ampere silicon rectifier
diodes are relatively inexpensive. Choose a set with reverse voltage
greater than three times the transformer's RMS voltage (2.83 plus safety
factor).

I believe the OA2 is a 150 Volt gas voltage regulator tube. That would
provide stability for the plate supply of your oscillator stage, or at
least its screen voltage supply.

The 6AL5 may be a dual-diode used as a meter rectifier. I'm not familiar
with the others, but you should be able to obtain their rated filament
currents to size the transformer's filament winding.

73, Fred, K4DII