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RCA T8-18
#46

Today I tackled the speaker again. Using the cone which I bought, I cut a slit from the center toward the edge, stopping short of the outer web. I then very carefully put it into the speaker itself, the outer edge centered where it should be, and the center on the voice coil flange. Sadly, my previous efforts to make it work precluded mounting it to the voice coil, so I knew I would have to make an inner part for the cone, but at least I could get it to approximately the correct angle. By overlapping the inner edges of the cut, I was able to reduce the depth of the cone to where it would work. If I hadn't screwed it up earlier, I could have used it like that, just cutting the center hole to fit perfectly, but that was not the case. Anyway, I marked the cone to where it overlapped, then took it out, cut off some of the excess overlap, but leaving enough for a glue surface, applied goop rubber glue, and clamped it together with the proper overlap as I had marked it. When it had dried well, I cut along the outer edges of the innermost circular ridge of the cone, to leave a flat gluing surface. I measured the diameter of this circle, and of the flange on the voice coil. Using these measurements, I then took a piece of fairly thick sketch pad paper, and drew concentric circles several large enough so that I knew that even bent into a cone, they would properly cover the flange on the remaining new cone, and several inside that I knew would start too small for the voice coil and range to being a little too big. These circles were 1/8 inch in radius different between them. When this was done I cut out the circle, and cut out the center hole, and cut through the circle on a radius line. Using the speaker itself again. I bent the circle into a cone of the proper angle and depth, cutting away the outer edges one circle at a time until it fit right to the edge of the last ridge on the new speaker, and overlapped the remaining flat part I had left. I also cut the inner circles so that the center fit perfectly onto the voice coil flange, leaving the center open, but covering the flange there nicely. I marked the edge of the circle of paper and cut off the excess, then glued the edges together using my marked line so it was at a perfect angle. When the inner cone had set, I glued it to the remaining professional cone along the outside, and to the voice coil flange on the inside, hoping that everything would work. It did fit perfectly, and the gluing went smoothly. Then I let it set. A little while ago, I tested the speaker. It actually works very well, decent volume, and no rattles or other nasty sounds. SUCCESS ! Lastly, a few minutes ago, I sprayed the inside of the cone flat black so it will look fine if there is any "see through" with the original grill cloth of this radio, which is in very good condition, and which I do not plan on replacing.
#47

OMG!   Icon_crazy  I'm impressed!
I was wondering if it was going to get sprayed black.
#48

Figured I'd post a picture of the rebuilt speaker.
[Image: https://66.media.tumblr.com/14a3e61aa681...1_1280.jpg]
#49

Very nice bud. Icon_surprised
#50

Things continue to progress nicely. Today my decals arrived from RD. My Solvaset also arrived which I ordered from eBay. I carefully cut out the decals, and applied them. They seem to be even better quality than the last ones I bought several years ago, the material seemed more durable so I could manipulate them into exact position without them breaking apart. Once they were exactly where I wanted them, and blotted with a microfiber cloth, I let them set for about a half hour, then applied Solvaset. They look great on the radio. Nobody but an expert would think they are anything but the originals in excellent condition. Even the experts might be puzzled since in my research I found such variation in the decals on these sets. Most haves no decals at all, and some had only an RCA logo at the bottom, and a range decal above that knob. Even these varied. In two pictures I saw the curved decal with colors matching the ones of the bands on the dial. In one I saw only letters, A, B, and C. I opted for letters only placed above the knob. I also put on the appropriate RCA Victor logo at the bottom of the set, but I also added volume, range, and power-tone under the appropriate knobs. Tonight or tomorrow, when the decals have had a good chance to dry out, I will put on another coat of tung oil over the set to protect therm, and maybe a second coat the next day. When the cabinet is done I'll post pictures.
#51

AAAAAARGH! Lessons learned the hard way stick the best. Decals and tung oil are NOT compatible ! I just tried to put a layer of tung oil over the decals I applied. I wanted to protect them at least a little. They came right off ! I mean RIGHT OFF! I was barely rubbing lightly and they began to disintegrate. I ended up removing them completely. It's a shame because they looked so good. Oh well. I guess this means that Deity has decided I should leave the radio without the decals. That is how the majority of the pictures of this radio appear, so perhaps that is how they actually looked, and the ones with decals are restorations which added them. At any rate, I am now going to leave well enough alone.
#52

Bummer Mike, but I guess that's good to know about tung oil and I'm sure your cabinet will look good anyway.

John KK4ZLF
Lexington, KY
"illegitimis non carborundum"
#53

The dial I ordered off eBay arrived today. Really nice and clear. I think it is probably printed even better than the originals were. It came all cut out, drilled, and ready to install. I took off the old dial and installed the new one, and installed the chassis in the now finished cabinet. It looks quite good, and works even better than it looks. I have only tested it in the daytime so far, and won't be able to test it well tonight. Our little town is having its Fall Festival, and a friend of mine is staying on the fairgrounds all night as watchman. I will be going down about 9, and staying all night until about 8 in the morning. I did the same last night and will Saturday night too. I'll probably give it a quick check before I drive down before 9 tonight though. Here's what it looks like:
[Image: https://66.media.tumblr.com/8610f9979430...1_1280.jpg]
#54

OH wow!!   Gorgeous!!!
#55

I just got back from my last night of keeping my buddy company watching over the Fall Festival. Last evening, while I was making coffee and filling thermos bottles and making sandwiches, I gave my RCA a test. It is working really well. Broadcast band is filled with signals all across the band, all of them within 1 tick of exactly where they should be on the dial, which is good enough for me. WLS from Nashville came is really strong, and I listened to The Grand Old Opry while I worked. I also checked both shortwave bands. Lots of stations on both ranges, although last evening I couldn't get WWV or CHU. It all depends on atmospheric conditions. I also live within 75 yards of 250,000 volt TVA power lines that go across my pasture, and they affect reception badly. They wipe out a lot of AM during the day. I have made a special vertically oriented antenna which minimizes their effect, and at night, when the draw on those lines is lower, reception is pretty good, despite some interference still. Another thing about the radio that I am very pleased with, the magic eye tube is working perfectly, and it really does make tuning right to the frequency easier.
#56

Good work and congratulations Mike!  Might be great to hear the world series on it!

I think there could be another category on the Phorum here for antenna discussions,  alone.  Interesting, complicated subject.




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