Phonoland

Hi All...this is my first time here and first post. I have just acquired a Zenith Cobramatic H661R AM radio and phono (1951?). This is my first older unit to fix up. I have some other junk worth nothing, but this one seems like something I want to keep and get working. The radio plays well, although the volume stays low.

Problem: The platter does not sping. The motor is working well and the small spindle spins freely...unless it is resting on the large wheel, which will not spin. Please excuse me if I use such terms as "thingamajigs", but I am definitely a novice. Here is what I have noticed:

Not having any clue as to how these things work yet, it appears to me that a part has been robbed from this phonograph. Under the platter, there is nothing that would appear to spin it. There is also no mechanism to operate the proper turning speed for the different types of records. If I hold pressure on the larger black wheel (pushing down away from the frame), it spins. When I let go, it stops. There is no kind of part to fit with this large wheel underneath the frame of the player. And, of course, there is no part to regulate speed. No matter the speed, everything spins the same (when I hold down the large wheel...the platter has never spun). I have also noticed an empty screw hole near the opening above the large wheel. It's obvious something has been there previously and is now gone.

Can anyone tell me what this part is that is missing? Is there anyone that could post of picture of the parts found directly under the platter of these machines? Any info would be appreciated. Thanks in advance...lots of info on this forum!

It sounds as though an intermediate idler wheel is missing but I can't say for certain without some pictures of what you are dealing with.

Thom

Here is a picture taken from above that shows what is just underneath the platter. There is definitely some entire assembly missing, but I don't know what. If anyone else has a picture from a working or intact Cobramatic it would help me to see what is missing and if I can't find a part, I might be able to construct one. Thanks again.

It might take me a day or two but I'll se what I have and get a pic to you. If someone can beat me to it...

I'll keep checking in...thank you sooo much!

This should answer some of your questions.

Thank you very, very much!!! I'll get to work!

Did you get your Cobramatic working yet. As you must have figured out, the large wheel is spring loaded and rubs against the changer base plate when the platter is removed. The weight of the platter on the intermediate vertical wheel pushes it down so it can clear the base plate and turn freely, and the speed is adjusted by sliding the vertical wheel to different positions along the radius of the larger wheel, a really ingenious and simple way of achieving continuously variable speed control. These changers were a very advanced design, they also featured an electrically activated trip mechanism and the last ones produced in 1957 had automatic shutoff and a lighted stroboscope.
If you still need the vertical wheel part, I have a 1955 model Cobramatic which is damaged and I could probably part it out. You can email me directly at famesteve@yahoo.com if you'd like.
Steve