I have had this radio for several years and decide that I really wanted to restore it. It is not in great shape but I hope to make it look great when I am done with it. This combination radio-phono has a 78 RPM turntable with a Crystal cartridge. It receives the standard broadcast AM band. The Phonograph has a record changer that operates in a Manual or Automatic mode.
I disassemble the radio and realized that one of the tubes was missing. It was the 50X6 and one of the other tubes was in the wrong socket. I ordered new old stock from Antique Radio Supply. I receive the new tubes in less than a week.
After replacing and testing all of the tubes I power it on using the Variac. The Variac gives you a great way to slowly bring up the voltage so that you can check for shorts or any odd conditions. I brought up the voltage completely. The radio started to work so that indicated that not too much was wrong with the radio.
The next problem was that the dial cord was broken. This is a common problem with some of the old radios. That is some of the most frustrating things to tie and re-string a dial cord but I got this one done in record time. If you ever have to do one there is a lot of you-tube info out there.
All of the capacitors need to be replaced. I replace the electrolytics first so that I would not have any power supply problems. In doing so I damage one of the tube sockets and had to go back and repair it. I am going to replace all of the other capacitors now and finish the radio rebuild.
I got enough working on the radio to start looking at the phonograph. I turned on the record player and the motor turned the turntable. I am sure that the motor idler wheel needs to be restored. They normal only lasted a few years before the rubber would crack and get hard and the idler would slip turning the turntable. I tried to check out the phono cartridge and it looks like it is dead. Oftentimes the crystal cartridge in many 1930s and 1940's phonographs will be found to be "dead." The active element in these cartridges is a Rochelle Salt crystal, which does not hold up well to heat or humidity and over the years they become inactive. Even if you were to find a NOS one they would be bad also. There are individuals that will rebuild one for you in the $45 dollar range. I might go this route because I understand they will replace your needle also. The needle in this unit is old and feels like it is worn.
I would take a chance on rebuild this cartridge myself but if I damaged it beyond repair I would not have a replacement for it. Here is a web-site that talks about rebuilding a cartridge:http://www.angelfire.com/electronic2/radiosean/tv/Cartridge-rebuild.htm
The paint is flaking off of the station dial. I have a friend that is going to see if he can reproduce the dial in a decal. I will get a new piece of glass cut to test that ideal. I have also gotten some model paint that I will paint the damage station numbers and back ground so if one thing does not work the other method will.
I still need to look at rebuilding the idler wheel. I reviewed one web-site that talked about cutting the old rubber off of the idler wheel and gluing an O-ring on the idler from the hardware store and then using a small lathe to grind the wheel flat. This will provide enough area on the wheel to drive the turntable.
Here is a picture of the radio:
Model 48-1256 used 6 tubes and included an automatic record changer. It received the AM band only. It was available in either Walnut or Mahogany.
Original selling price: $124.95 (walnut), $129.95 (mahogany)
Number made: 18,723 (walnut), 28,003 (mahogany)