"Arfa Daily" wrote in message
...
Anybody out there got any original Rockola service manuals ? I need a
decent copy of the schematic for a 1478-85 stereo tube amp. There seems to
be plenty of copies on line, but all sourced from an original poor
resolution scan-to-jpg. I particularly need to know what the AC voltage is
from the transformer winding that feeds the HT supply for the amp. You can
read the text at the heater supply winding as 6.3 V as you would expect,
but the HT winding's voltage is illegible on the scan, no matter how much
you zoom it.

Arfa

What voltage rating on the filter caps? That will give you a maximum point.

What tubes are used? That would give you a design window.

Is it center tapped?


tm