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Re-forming applies to the power supply electrolytics. If they are new and
correctly wired, there should be no problem with those capacitors.
Without the rectifier, you can turn up the variac as slowly as you wish, but
when you do the test with the rectifier in place, dont run the unit under
say 80% of nominal voltage for more than a few minutes. If it seems
to be idling OK at 80%, you can get it up to 100%. This radio is much simpler
than a TV, where for instance lack of horizontal drive could fry the sweep tube.
Also, in addition to what I wrote to you last time, you should do the initial testing
with rectifier with the function switch in PHONO or STEREO, rather than
RADIO (or BC). This will keep the two radio tubes off the high voltage.
Of course, this test should be done with the speakers (or load resistors) connected.
After checking the high voltage at C23, the next measurements should be
the cathode voltage at the output tubes (pin 2 of each 6AQ5, 12 volts) and
at each of the driver tubes (pin 7 of each 6AU6, 1.1 volts). Correct values
at these four points will almost certainly guarantee that the tubes are correctly
biased.
Once you get the audio section working, we'll have a look at the radio part.
Good luck.
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