The PHILCO Phorum

Howdy -

I haven't been active in here lately because I'm battling stage 4 oral cancer so my efforts have been diverted to the obvious.

But until they start shoveling dirt over me I have a question about a Crosley 56TX I just got for cheap. I know it ain't a Philco but the question applies to ALL antique radios and the response times on this forum are excellent and the knowledge base is as good as it gets. So many of you should take a bow.

I now know why I got the Crosley for cheap. The seller went into it pretty wildly and his wiring ideas might be from another galaxy.

I took his word that the radio powered up but had no sound as the only issue. Never again will I trust a seller on word alone. I don't think he meant any harm but he got in over his head and the cleanup will be a pain for me especially since I'm not too swift at interpreting schematics, let alone Crosley schematics.

After I plugged the radio into my iso transformer and flipped the power switch on the transformer the dial light came on and the tubes started to glow. He was right about no sound but the first problem was obvious. I went to turn the switch on the radio off but it was already off. He had wired the AC power cord to basically bypass the switch.

I'm confident I can clean up the power cord wiring (especially since I'm going to make it safer) but he had the switch/volume control wiring all over the place. There was no connection to AC and there was a loose wire that I suppose he meant to connect to a pin on the rectifier.

What I'm trying to remember (since I'm going to redo all his switch wiring) is which connections I should make to the rotary volume control. This type of rotary switch is in all kinds of old radios not just Philco and Crosley. It has 3 terminals on the side and 2 on the back. I thought I should connect AC power to terminal 1 and a 20 ohm 10W resistor to terminal 3 with terminal 2 for wiring to capacitors, tube pins or whatever. I guess I need a refresher on those 3 terminals but I also definitely don't remember what should connect to the 2 terminals on the back of the rotary switch.

Hep me hep me I'm losing my mind!

Sorry to hear of your health issues.   Here's a link to the Crosley 56TX schematic.

If I understand your questions correctly ... Usually the switch with 3 terminals on the side and two on the back are as follows.  The center of the 3 terminals is usually the wiper on the volume control resistor and the two end terminals correspond to the two ends of the resistor.  The two terminals on the back side of the switch are usually the on-off switch.  The on-off switch often fails, sometimes just from being dirty and sometimes from other problems.  

Here's a Philco 60MB volume control image:


I moved your thread to the non-Philco radios section.

OK so what goes to what?

Should I connect my hot wire of the AC cord to one of the terminals on the back?

Yes, you connect one side of the AC line to one of the two terminals on the back of the switch (one of the arrows in the image Bob posted above). The other terminal of the switch (the other arrow in the image above) will go to B- or, in this case, the negative terminal of the dual electrolytic capacitor 17A/17B.

The other end of the AC line will connect to pin 2 of the 35Z5.

I am so sorry to hear of your stage 4 cancer. I am currently battling stage 4 cancer myself. Keep plugging away at that radio when you are able to...it will help you forget about the cancer. That strategy is working for me so far.

Thanks for the clarification Ron and bless your heart for the encouragement.

I feel the same way - I'm certainly not giving up I'm just trying to make jokes about my mortality to help get me through. If I was 23 instead of the 63 years old that I am I would much more depressed. I would like to leave my niece some radios to keep or sell (like those 2 beautiful Hippos I have restored) because I want to help preserve old radio Americana as much as possible. I drive past the WLW AM broadcast tower and Voice of America museum almost every day and it makes me want to dig into some circuits.

Thanks again and good luck.

+1 what Ron said.
I would also check out that switch before I rewired it. I suspect if had failed and that is why it was bypassed. If it has failed and you can not repair it, then contact Mark Oppat and see if he has a replacement or can repair yours. http://www.oldradioparts.net/controls.html

That's a good point - before I just wire it up for disappointment I'll ohm it out and see what's what.

Also thanks about Mark Oppat.  It seems like I've seen some of his merchandise before.