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Philco 90- not much volume
#1

I have recapped my Philco 90A (early model w/45 push pull tubes) and replaced a couple of out of tolerance resistors. All tubes check good, all shields in place, bakelites restuffed. I am receiving 2 stations very clearly, the loudest is close to my home, the 2nd is a little farther away and not as loud but still easily hearable. After this I have to really strain to hear other stations. Is this all the volume I can expect on farther stations with this radio? I am using a 100' wire antenna 25' off the ground. My RCA 17K is picking up a 1000w station 30 miles away right now like it is next door. Have I missed something? Thanks for all suggestions,
Doc
#2

1. Have you performed the alignment? Without it your gain could be really off.
2. Just in case check the Antenna input RF coil 2 for continuity, and also the primary of the coil 7 (or which is the same, plate voltage on the first 24A tube).

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#3

As Mike said, most likely an open winding in one of the RF transformers  Check to make sure you have plate voltage on the 24 tubes.

Steve

M R Radios   C M Tubes
#4

I'm on it. I'll let you know what I find. Thanks!
#5

While checking voltages I found a 1 meg resistor to the grid of the 1st audio tube that was reading 2.5 meg. Replaced it and now this thing is blasting all across the dial! Thanks guys.
Doc
#6

Congrats. Still, do the alignment.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.




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