before & during work
It was owned by a heavy smoker by the looks.
Done, with old tubes installed for checkout. I have done some cleaning,
but more will be done.
I installed Ken Simpson's suggested mods, back-to-back diodes on the meter, and a diode across the antenna coil.
With my shack wattmeter, the old tubes (both OK) will get over 500w output on all bands, driven with approx. 100w from my Ten-Tec Omni V. (The wattmeter used is 500w f.s.)
the above pix are after mods, before cleaning, show heavy nicotine stains, and
it smells when hot.
compare with the ones below, should look cleaner. I only did light damp cloth cleaning on the front panel, the paint & lettering will come off if scrubbed.
I will install old, then new, tubes and put the "big" wattmeter on it to compare readings.
Here's what I'm getting for power readings:
Freq. Ip, ma. Pwr out, watts Load
3780 500 740 3
7280 500 840 4
14280 500 900 5
21280 500 900 4-1/2
28280 400 450 5-1/2
Not very efficient on 10, that load setting gives the max. power out The input ckt tuning has little, if any, effect on 15 & 10m. Input SWR is about 2:1 on those bands, so it's not a mismatch.