Modifying an old Radio to accept an MP3 Player - help needed

[FoleyF]

Hello everyone-

Not sure if this is posted in the correct forum, but I wanted to ask a question. What would be the best way to take an old 1950's table top wood radio and modify it so it can take an input from an MP3 player. I'm not sure how big a job it would be and if I could do it, but I would like to try. I have thousands of Old Time Radio shows that would be cool to play through a radio from a similar period.

Any suggestions would be greatly appreciated. I'm not an expert, so please provide as much detail as possible.

Thanks,

Foley

 

[kevinkr]

Probably wiser/safer to just buy or build an rf modulator, that way you do not have to modify the radio. Many vintage radios have hot chassis designs and are hazardous to modify - isolation transformer required on the mains.

If you are talking tube radios this probably belongs in tubes.

 

[dangus]

Some old tube radios had RCA jack inputs for record players. I'm not sure what, if any EQ you might need; I think they were intended for cheap crystal pickups. Presumably those sets would have had power transformers for isolation, unlike the cheaper ones that had 50C5, 35W4, etc tubes designed to run off line voltage when the filaments were in series.

 

[Steerpike]

The easierst place to inject audio is onto the two "outter" tags of the volume control pot. One side of the pot will be earthy - thats where the screen/shield gets soldered.

You may need to cut the existing connection to the top end of the pot, to eliminate AM hiss from the detector stage on top of your MP3 audio.

If it's a live chassis design, you need an isolating transformer - doesn't have to be in the mains, can be in the audio line-in you are adding.
I've used an old tube-amp output transformer for this purpose, or just buy one.