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What is with the cones on these old RCA radios? This is the second one I have had to repair. While I was doing the alignment and testing the radio on all three bands, I noticed distortion when the volume was at all above medium low, getting worse with increased volume. I had looked over the speaker quickly before I began to test the radio, and it looked fine, but there must have been a little crack forming where the cone attached to the voice coil, which just got worse as I used the speaker. So, I repaired it. I used a compass to draw two concentric circles one well outside of the crack, and one just a hair bigger than the center where the voice coil is. I then glued it well to both the voice coil and surrounding cone using RTV rubber cement. I slit the circle from the outside to the inside diameter, so that it could overlap slightly as it accommodated for the cone shape. Now I have to let it sit a day or so for the RTV to set up well before I proceed further. I need to start on the cabinet anyway. The radio itself is working fine.
[Image: https://64.media.tumblr.com/43b11c50c1b5...69fc0b.jpg]
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Never tried RTV will have to give it a try in the near future. David
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Today was beautiful here, sunny and warm. I took the cabinet out onto my side deck and began to work on it. I took off the dial bezel with the dial glass, which is easy, just 4 screws. Then I removed the little hood that goes over the magic eye. The way these are mounted it seems they never expected anybody to ever remove them. They just push in fit in a hole with virtually no clearance, and are held by little barbs punched into the sides of the tubular part that pushes into the hole. One must be very careful removing them or you can damage the face of the cabinet when the little barbs pull at the wood. I managed it with no noticeable damage, what little there is will be covered by the rim of the little hood.
I considered removing the speaker mounting board, but when I had removed the 8 screws holding it to the rest of the cabinet, it seems it was also glued in place, so I said "to heck with it" and decided to just be VERY careful with the grill cloth which is original and is in great condition. I screwed it back. Then I proceeded to clean the whole outside of the cabinet with GoJO. At some time the cabinet had been around where someone was painting with white paint, and there were a lot of tiny specks on it and a few larger ones. These came off after rubbing with more GoJo and then careful scraping away with my thumb nail. The results of the cleaning with GoJo were so good that I decided to just give the cabinet a couple of coats of tung oil, and leave it at that. It will look like the well loved, venerable, 85 year old lady she is.
I let the cabinet dry in the sun for a few hours, then rubbed on a thin coat of tung oil. This brought the finish back a great deal, hiding minor scuffs and scratches. It already looks quite good, and will look even better after a couple more coats.
I also cleaned and polished the little hood for the magic eye, and the bezel for the dial glass, both of which appear to be stamped from copper or bronze. I do not completely polish them, but leave some patina in the crevices which accentuates the pattern, just as one should do with fine silver. They now look REALLY nice, and will suit the feel of the cabinet, not new, but classic.
It is going to be a while before I actually finish this radio. Doing the alignment I could see how very faded the original dial phenolic is, so I ordered a new one from Renovated Radios. That means this saga will go on for at least another 10 weeks. LOL !
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Do you have a brand or type of Tung Oil you like? I know Minwax has Tung with something mixed in.
Paul
Tubetalk1
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I used to use Homer Formby's but right now I am using Minwax tung oil. I find it dries a little faster than Formby's which allows re-coating a little quicker. I always rub on THIN coats, so it takes several, and the quicker drying is a plus. I do miss Formby's tinted tung oil finishes though. Haven't been able to find them in years.....
I just checked, and it seems that Formby's was bought out by Minwax. That explains things.
(This post was last modified: 08-09-2021, 06:43 PM by mikethedruid.)
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I received some more of the metal tubes I ordered, the last I needed to completely replace the glass ones used where metal should have been. Tested the radio with the repaired speaker. It took care of the distortion problem. I also re-checked the alignment, found it was right on. Earlier, I rubbed a second coat of tung oil on the cabinet. Looks even better now. Really, the only thing left is to wait for the dial to come from Renovated Radios.
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The past couple of nights I have been playing with the chassis and speaker on the bench. There was STILL a distortion at higher volumes which I had some trouble tracking down. Finally traced it to a tube socket. cleaned all the contacts, put back the tube, and the distortion is gone. I also installed a rubber grommet into the hole through which the wires to the "magic eye" tube pass. They merge together into the cable right at that hole, not below it, so were easily subject to chafing from the metal, although still in good shape. Don't need those kind of problems so I installed the grommet.
I also was not satisfied with the alignment, so used actual stations on the various bands to get it exact, and then to tune the RF and antenna stages once the oscillator was dead on at the high and low end of the bands. Man, does this set suck in the stations now, even with my short test antenna on my bench ! Nashville, Louisville, Chicago, New York all came in clearly. Best of all, clearly at even high volumes with NO DISTORTION !  Shortwave is booming in on both tuning bands too, with WWV right where it should be.
So, last night I made the brackets to hold the "magic eye" tube in the cabinet. The original bracket was missing from the radio. I used sheet tin to make the two side pieces, and used a hose clamp over them to clamp the tube base. I installed the brackets today. Here are pictures...
[Image: https://64.media.tumblr.com/f123f8bccb2a...a6a9b6.jpg]
[Image: https://64.media.tumblr.com/9ee316523bc9...c6b61b.jpg]
[Image: https://64.media.tumblr.com/cc631495007f...2a81f6.jpg]
[Image: https://64.media.tumblr.com/911353c98dae...e0760d.jpg]
So, now I am waiting for the dial to arrive. It is on its way, and should arrive Monday, which was a pleasant surprise. Pretty quick for Renovated Radios. He must have had one in stock. Once I install that on the chassis, I can re-install the chassis and speaker into the cabinet, do final testing, and it will be all done !
(This post was last modified: 08-14-2021, 02:20 PM by mikethedruid.)
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To my pleasant surprise the dial for my RCA C9-4 arrived today, ahead of schedule! I installed it this evening, and did a final tweaking of the alignment. The radio is working well and is very sensitive on all bands. I was able to clearly pick up WWV at 5 MC on band B, and 10 MC on band C, as well as many other stations on both bands in all the appropriate places. I use WWV to double check my alignment, and they come in right where they should, not even a single tick off ! Mind you, all this is on an antenna that consists of about 10 feet of wire inside an aluminum insulation shielded house ! I won't be able to try it on my outside antenna until I install the speaker and chassis back into the cabinet tomorrow. I can hardly wait. Anyway, here are pictures of the new dial. It is MUCH clearer than the old one, much easier to read. The old one was all there, if you looked really close you could see all the numbers and letters, but it was very faded. Anyway, here is what the finished chassis looks like on my bench playing the Grand Ole Opry on WSM 650 AM.
[Image: https://64.media.tumblr.com/fe3b7798b62f...e598dc.jpg]
[Image: https://64.media.tumblr.com/b8786f6c64c9...b32bce.jpg]
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Like the Tuning eye off to the side  .
Paul
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When did Renovated Radios start producing reproduction dial scales? I thought Ed was trying to sell off remaining stock and close up shop?
--
Ron Ramirez
Ferdinand IN
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You're right, Ron. It was Radio Daze I ordered it from. Too many vendors, and too tired, got confused. Oh well, I'm running out of room for radios anyway. The Scott may be my last new adventure. I have a few small ones which I haven't gotten to yet, and a few I redid YEARS ago which I could tend to. But as for new purchases, I think it would have to be an extraordinary set at an extraordinary price to get me to buy. With the price of everyday necessities rising as fast as they are, I think I will have other things I will need to spend my money on. Radios, and the parts to restore them, will be the least of my worries.
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Well you have some to listen to at least......I am waiting on cooler months to start to make some stuff that keeps for fridge, sauces, chili, etc....stretch the food budget.
You run out of stuff to work on I can send some stuff your way . Been cleaning in the cellar and some things need fixin and some radios just need to go.
Paul
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IT'S DONE ! I put the speaker and chassis back into the cabinet today. Tonight I will give the radio a test with my outdoor antenna. Here's what she looks like...
First a "BEFORE" picture to remind you what she was like when she arrived...
[Image: https://64.media.tumblr.com/be2596a7c767...6197b6.jpg]
And now for the finished product...
This one is taken with flash...
[Image: https://64.media.tumblr.com/b5924067dc4e...313a9e.jpg]
Without flash...
[Image: https://64.media.tumblr.com/67ed74dcc7dd...3890f7.jpg]
The dial all aglow...
[Image: https://64.media.tumblr.com/d70e63cba724...1f6dd5.jpg]
The dial with flash, showing decals (the originals !)
[Image: https://64.media.tumblr.com/9f4c08ab37f5...c1277b.jpg]
If things go well tonight, I'll make a video.
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