[Jayce]

I already posted this radio in the finds topic, but here is where I will tell the story of resurrecting it from the dead and ask for a little help for the future.

   

I had really been looking for the Channel Master Super Fringe model, but recalled this radio had been sitting in the backroom of my buddy's appliance shop since forever. One of those flea market buys he had made and it just hummed and would barely pull in anything, so it got stuck on a shelf until early this afternoon when I fished it out and began checking tubes and trying to clean controls. All the tubes were original and all were bad except for the 12AV6 at least at first. The hum was from a dirty volume control that I had to hold the radio at odd angles to get to. Also the control is loose, but I cannot get the chassis out. (More on that soon.) Anyways, it did come back to life, but was not happy on AM and was a bit muddy sounding so I swapped out the 12AV6 which had started coming up as questionable on his checker. AM came back to life and the radio sounded much better. Upon getting it home, it was still touchy with a buzz in the left speaker, so I pulled the 50C5 I had swapped for the weak 35C5 and put in my last new 35C5. Even happier radio though it does NOT like my one local station on FM. (Big surprise there, few of my vintage radios do.) The more it is played on the smaller station, the better the radio sounds and it is not your typical dual speaker setup. The left speaker is a larger oval speaker with a much smaller one on the right and there IS a crossover cap, so a basic hi-fi setup. Seven tubes pick up rather well and it sounds good as long as the station isn't getting overboard on the bass.
Now for a question for help. How do you get this radio apart?! I thought I had enough speaker lead to tighten and clean the controls, but the two dial pointers run on a separate metal track that mounts to the cabinet. How the heck do you get this separate piece loose without fouling up the dial cord? Someday I will need to get in there.  
By the way, it appears this radio was made by Sanyo for Channel Master.

[Arran]

Jayce;
  I can't tell you how Sanyo worked their dial cords, but on the two Rincan radios I have the pointer had to be rotated, and slipped through a slot behind the dial, which meant that you had to remove the plastic dial first, and obviously the knobs ahead of that. It's possible that the Channel Master has a screw or clip attaching the dial cord to the pointers, which has to be undone, if you can find a Sams for this radio, or post a question on the barking dog forum you may find the answer. All that I can say about Japanese electronics from this era is some of it was very crudely built, and not well designed, I hope that you can find a simple way around your problem and can get the chassis out, at the very least it will probably need the audio coupling caps changed, unless Sanyo used disk caps.
Regards
Arran

[BrendaAnnD]

In my experience with this style radio, the dial pointer is attached to the string with a small clamp. You would loosen the clamp(s) and move the string out of the way, then the chassis should come out.

[Jayce]

Thanks so far. I thought about taking the plastic dial scale off yesterday when working on the radio for better access, but all six screws are stripped and refuse to come out. A couple started to back out then just spun. Tried the old trick of gently prying on the dial scale while turning the screws to coax them out, but that failed and I didn't want to break anything. You can wiggle the dial scale, but those screws are STUCK! Getting the dial scale off would help me examine the situation a bit better. So far the radio works fine, but someday soon I want to recap it. My buddy said the good thing about these 60's FM-AM radios is that they are 'young' enough that they very well might have another ten years of life on them. All I know is that the Channel Master is sounding and working better than my 1962 Panasonic, which will be getting serviced soon.

[Jayce]

A little update, the radio is now working even better after acting a bit odd earlier today. Why? When I checked the tubes I somehow missed the original 12BE6 that was sort of hiding behind an IF can. It was pretty much like the rest of the original Channel Master tubes I pulled out, about kaput! I put in the last good, used 12BE6 I had and it now sounds and works even better so far. One of the 12BA6 sockets as one of the pin contacts floating up and down when I move the tube, so am glad I replaced the tubes now. I think I'll use it as a daily driver until it dies and then redo it or at least redo it after getting a few more Zeniths and the Panasonic done. My buddy is getting the point where he might stop redoing AM-FM radios as they can be really cranky and the cases of SMD are getting worse.

[radiorich]

Hello jayce,
Am/Fm sets are more work to troubleshoot and to restore anyway I have like 3 or 4 of them in my collection of about 200 sets .

Sincerely Richard

[Arran]

One good think about the Japanese tube sets is that they used molded mica or ceramic caps in the IF cans rather then the crappy silver mica ones that plague North American sets, it's probably why many of them still work The Japanese sets often used oil caps in them which were batter then paper at the time, but many of them like to short now that they are in their 50s.
Regards
Arran

[Jayce]

Now that is interesting. Would explain why I haven't yet heard of a Japanese set with bad IF cans, even the real cheap radios they made. I did find out that 'bar' is actually attached to the chassis after all and only screwed to the front of the cabinet for stability. Only hurdle to taking it apart for servicing later is getting that plastic dial scale off to work the dial pointers through.

[Jayce]

Well, the radio did conk out, but at least I have an idea how it comes apart now and it will be worth rebuilding if the IF cans are as Arran says. Nothing more frustrating than getting a radio going only for it to develop the dreaded SMD. In fact, a recently recapped GE might be doing that to me now. GRRRR!

[Paul Philco322]

Good luck. I know a guy who works on many of these type sets, he is in NH though.

Paul

[Arran]

Jayce;
 Silver mica problems are not usually an issue in Japanese export tube radios, they seemed to like using either ceramic or molded mica, not the mica sheets like North American sets use. If the set conked out it was probably an audio coupling cap, or bypass that decided to go leaky, or open.
Regards
Arran