Edison C4 Turntable WORKS!!

[CDBPDX]

I brought home an Edison C4 recently that had been sitting in a barn for several years and didn't hold much hope that anything was functioning, but I found out at least the turntable still works just great! That is, it goes 'round and 'round just like you'd expect. It is also extremely quiet. The speed control works great, too. 78 rpm is dead center on the speed control dial.

You can watch the turntable spin on YouTube at: http://youtu.be/PXNufBPzgiA

Haven't tried the reproducer yet..Do I need a special needle/stylus for the reproducer?

Also, there appears to be 2 radio/amplifier chassis. The upper one seems to be all there, the lower one is missing a tube. All the tubes present match, all being Cunningham brand. I'm hoping that everything will work when I figure out what tube to install.

The cabinet is solid but the surface is not so wonderful. Needs lots of glue and surface restoration.

This is fun! CDB

[Wolfe]

Did the Old Man have anything to do with the development of this?

[ChuckA]

I brought home an Edison C4 recently that had been sitting in a barn for several years and didn't hold much hope that anything was functioning, but I found out at least the turntable still works just great! That is, it goes 'round and 'round just like you'd expect. It is also extremely quiet. The speed control works great, too. 78 rpm is dead center on the speed control dial.
Haven't tried the reproducer yet..Do I need a special needle/stylus for the reproducer?
Also, there appears to be 2 radio/amplifier chassis. The upper one seems to be all there, the lower one is missing a tube. All the tubes present match, all being Cunningham brand. I'm hoping that everything will work when I figure out what tube to install.
CDB

For needles you just use common steel as in any other phono of that period. You will need to rebuild the reproducer as the rubber dampers will be hard as rock and will tear up any record you play. The top chassis is the radio, bottom is the power supply/amplifier. You will need to restore the electronics also, not a lot of fun as all the caps are in tar filled cans.

Here is page from service manual showing tube layout for the amp:

http://www.myvintagetv.com/posts/c4_amp.jpg


Chuck

[marcapra]

I also have a C4. The turntables always seem to work on these. The radio and speaker are another story. If your speaker has an open or a short it can be expensive to fix. It can be very hard finding someone who can repair these radios. I had a pro working on mine for a year and he still couldn't fix it! The speaker had an open and guy that normally rewinds these got too old to do it. So I found a parts chassis that hopefully has a good speaker. He rebuilt the power supply, but had trouble fixing the radio. So if anyone knows someone who can fix this, I'm in the So. Calif. area. I also have a 1930 Edison R6. To the guys who asked if the old man had anything to do with these, I think the answer is no. His son Charles was in charge then. Thanks.

[ChuckA]

I also have a C4. The turntables always seem to work on these. The radio and speaker are another story. If your speaker has an open or a short it can be expensive to fix. It can be very hard finding someone who can repair these radios. I had a pro working on mine for a year and he still couldn't fix it! The speaker had an open and guy that normally rewinds these got too old to do it. So I found a parts chassis that hopefully has a good speaker. He rebuilt the power supply, but had trouble fixing the radio. So if anyone knows someone who can fix this, I'm in the So. Calif. area.

Not sure why a "pro" would have a problem with this radio, it's a simple TRF set. Annoying to work on due to all the potted parts (typical of 20's designs), but easier to work on than a C2.


Chuck

[CDBPDX]

For needles you just use common steel as in any other phono of that period. You will need to rebuild the reproducer as the rubber dampers will be hard as rock and will tear up any record you play. The top chassis is the radio, bottom is the power supply/amplifier. You will need to restore the electronics also, not a lot of fun as all the caps are in tar filled cans.

Here is page from service manual showing tube layout for the amp:

http://www.myvintagetv.com/posts/c4_amp.jpg


Chuck

I took the reproducer apart and probably killed it to death. The piece where the needle goes is badly corroded but fixable, I think. There is a very small copper coil mounted in between 2 ceramic(?) pieces and the needle holder is in the middle of that. I unscrewed the 2 ceramic pieces and it all came apart. Now I have a copper coil with 2 ends of incredibly thin copper wire sticking out. I assume they were attached to something before it all fell apart...??

At least it has a cool magnet. I had no idea. CDB

[marcapra]

My C-4 came with two pickups, one was hiding down in the record compartment along with some 7" kiddie records from 1929! George Epple is the expert on rebuilding these horseshoe magnet pickups. I've used him many times and he always hits a homerun.

[mf77]

The piece where the needle goes is badly corroded but fixable, I think.

Now I have a copper coil with 2 ends of incredibly thin copper wire sticking out. I assume they were attached to something before it all fell apart...??

At least it has a cool magnet. I had no idea. CDB

The piece that holds the needle is called the armature. It should have soft rubber sleeves on it, where it is held by the mounts. These hold the armature centered in the coil and allows the armature and needle to move within the coil.
This movement interfers with the electrical field created by the coil, and it's the changes in this field that basically reproduce the recording.
The 2 wires coming from the coil are your positive and negative leads, and should attach to 2 poles that are in turn attached to the 2 wires that run through the tonearm to the amp.
Be very careful not to break one of the leads off at the coil, as this will render a good coil useless, and they can be very expensive to replace or have rewound.

Generally speaking, electric pick-ups are very simple to restore, and IMO far quicker & easier than restoring an acoustic reproducer, but if you're not sure what you're doing, it's best to give the job to someone who does.

This page may help you understand better how these early pick-ups operate, and makes good reading if only to see the different types & designs used for electric pick-ups in the early days.

http://www.normanfield.com/pickups.htm

Whenever you pull down one of these magnetic pick-ups, it's important to handle the magnet gently, as dropping it can decrease it's magnetism. You should also put an iron nail across the poles of the magnet as soon as it's removed from the pick-up as this will help preserve the magnet. If the magnet seems weak, you should have it properly remagnetised, as the stronger the magnetic field is, the more sensitive it becomes, resulting in better sound reproduction.