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Adding phono input to a 37-650X
#1

I am just finishing up a restoration on a really nice 37-650X console.  I all ready have a half dozen GO To radios for short wave listening so I would like to configure this radio to play  my RCA 45rpm record player/changer.  Specifically a 45-J-2 I recently refurbed.  I have spent quite a bit of time researching this but have more questions now than I did before I started.

So my thoughts are to cut the wire between C40 and the junction to the left of it and install a SPDT switch to switch between radio and phono.  Input record player input at top of C40.  Should I put a .01 cap in series with phono input?  Should I put another switch to remove ant input?  

Any help would be appreciated.  Like I said this is a beautiful radio and I don't want it to sit around gathering dust.  I have a BC-348Q, SX-100 and Sx-99 and several others for shortwave listening so I really don't need another SW radio.

Thank you very much for your time
KK4KRU

Schematic
#2

I added a jack for a bluetooth reciever to my 37-650x, it works fine. Should work for your phono. Mount a jack aand a spdt on the rear of your chassis. Since the radio is mono you need to combine the stereo channels. Connect a 1K resistor to each side of the jack. Connect the 1K resistors together and to a 1 Meg resistor. Connect the 1 Meg to ground. Connect the junction of the 2 1K and the 1 Meg to one side of the SPDT switch. Disconnect C33 (.01) from the junction of R31/R32. Connect C33 to the center terminal of the switch. Connect the other side of the switch to the place where you disconnected C33. Connect the third pin on the jack to ground.
Enjoy
Kelton
W4IND




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