RCA Victor 3-RF-91

Hello, I am new to this forum and this is my first post. I have a RCA 3RF91 radio that had all caps and electrolytics replaced recently. The radio works great when in AM and phono and has very loud volume. However when switched to FM the volume has to be turned almost all the way up to hear anything. It tunes in stations pretty well while in FM. I am fairly new to this new hobby and am still learning. Does anyone have any thoughts as to what could be causing the volume issues on my radio  Thank you!

Welcome to TRF. First, have you tested the tubes? Could be one of the audio tubes is weak.
Could also be anything else from low B voltages, to a bad speaker.
Yes, I have seen that happen.

Hey Bill, Thank you. I don't have a tube tester yet but I thought about ordering some nos tubes from findatube.com. I figured it couldnt hurt to have some spare tubes for future use if needed. I will have my friend who originally replaced the caps show me how to check the B voltages. He has been restoring tube radios for many years and has been kind of a mentor to me.

Did you buy it from him? If so, he should be ablt to fix it for you.

No i actually bought it off ebay but he has been helping me with the radios that need more than a simple recap.

Sounds like this may be one of them.

Just as a suggestion, try cleaning the band switch. Also wiggle the tubes to make sure you don't have a dirty tube socket. There may be a bad solder joint or connection somewhere that carries the FM signal.

Regards

WC

Also you could have a misaligned IF can or weak tube in the FM portion or( lack of antenna  )

I thought he sadi the am is also weak.

No just the FM Bill

Thanks, Tony.

Thank you all for the advice. I went through the radio and checked the tubes to see if the were loose. some tubes were pretty loose in their sockets so i VERY carefully pinched the contacts in the tube sockets with some needle nose pliers to make a better contact with the tubes. I will try cleaning the band switch later today. Also, using an antenna had no effect on the FM volume.

Well you know where to concentrate, since the AM seems fine and the audio for AM also plays good you can eliminate those two sections, I would suspect in the FM area, by looking for cracked leads, a coupling cap or bypass cap. Thoroughly inspect solder joints and resistors that have changed value, also check the bias voltages to the grids. Hopefully you don't have an FM IF can that is open so do resistance checks on that just to be sure. Especially if the tubes check OK and bandswitch isn't faulty. Does it look as though the set has been repaired in the past? If that's the case then suspect wiring errors and solder blobs that can short parts, and of course cold solder joints.

One last thing try the old pencil tap test to also check for loose parts, shorted tubes and bad connections.