Home Forums Reply To: Philco 37-650 Plate voltage

Rick D
Forum Participant

Hello Jean
First of all thanks for your reply,I checked the voltage across #57 cap and got 377 volts and on the
field coil resistance I got 413 ohms and on the primary winding I got 3.5 ohms,and on the heater voltage
on start up 6.9 volts and then down to 6.8 volts.I have run this set several times for about three to
four hours at a time and find that after about two hours the problem starts,it,s ok when it is just
talk on the radio,but when any music comes on with some volume the bass seems to make the speaker
sound if it is rubbing or torn,like there was something leaning on the cone and vibrating,if you
turn it down it,s ok,I have tried three different speakers,good ones and it,s the same,I have felt
the power transformer and that is just a bit warm,and the field coil on the speaker is cool,any
ideas on what to try would be great,sounds like I have to get the plate voltage down some how,
only thing I don’t know how or what to do about it.I have put a lot of work into this set,all new
caps,and those black tubs aren,t much fun,thanks for any help all the very best Rick