[Johnson] Thunderbolt Q & A

[Mahlon Haunschild]

I don't subscribe to ER; please tell me more.  But dropping the plate
voltage doesn't seem very precise and means Ranger surgery.

Sprague OY-series 2-watt ceramic composition resistors (available from
digi-key, Mouser, and others) are nicely non-inductive.  Panasonic
metal-oxide-film power resistors should be OK too.

"
Actually, it might be better just to install the "temporary mod" that
was shown in Electric Radio several issues back. What the mod entailed
was breaking he power
supply feed to the final amp and install in the break's place a voltage
dropping resistor to cut back the output power of the finals.
Additionally, a switch is put in
parallel of the resistor. The advantage of doing it this way is that if
you have to run the Ranger into the T-bolt, you can drive the amp at a
lower power due to the
dropping resistor in the mod. If you want to bypass the amp and run the
Ranger barefoot, simply switch out the resistor. The bonus is that you
can easily get a wire
wound resistor to drop the voltage. It may be slightly harder to find
carbon power resistors that will handle the power for attenuation and
you don't have that added
bonus of switching out the swamping resistor. 
FWIW. Cal, N6KYR. "
-- 
regards,

Mahlon - K4OQ