[morzh]

The dreaded moment has come: I have just put on my table the AK808A I bought last summer.
Wow, what a serious animal.

Philcos are the simplicity itself compared to this. I am trembling and shaking in my slippers.
I also did not realize this one has a shadowgraph.
Mamma mia, Dominus mecum est.

Anyways, the much dreaded Gutta Percha wires are mostly in good shape and not only not cracked but even feel soft to the touch.
That is most of them.

There are some that are well cracked, the black ones, that carry the filament voltage, red (same signal, coming from the power transformer), a couple of beige ones.

The wires coming out of RF cans to the tuning cap / grid caps are very much frayed, will have to be replaced.

I love their resistors, they are colored so vibrantly, it feels almost sacrilegious  to cut them out.



All the grid cap wires have that one-end wrapped wire around them (like that one in some Philcos, like in 80 I think or 84), will have to think how to best replace it when I change the frayed ones.

Well....first things first, coil check, transformer buzz-out and such.

[Arran]

Mike;
  Some of those A.K transformers also feature rubber/gutta percha covered wires, I don't know about the 808A though. With regard to the resistors are those the kind with the metal ends or are they the more typical radial lead types with the body-end-dot code?
 Like I was saying about the wiring in your new 41-280, different coloured wires seem to deteriorate at different rates, but I guess it depends on who supplied the wire, or the batch? In Rogers built sets the worst stuff for rotting was the green and blue wires, the white and yellow held up the best, and the other stuff was somewhere between the two, obviously the black and red ones are the bad guys in A.K sets.
Regards
Arran

[morzh]

Arran

The resistors the same type as Philcos from 20/70/90, with metal (tin-led) ends barrel-shaped ending with cones.
The color code is likely proprietary or at least it is not your "Bad boys...." thing as "Red+Blue" means 100K, "Red+Yellow" - 250K, "Blue+Grey" - 1M etc.


there are 4 flex resistors under the chassis and also some under RF chassis.
One (670 Ohm) is missing and replaced with a wire (green cloth covered), and one (2kOhm) is replaced with a regular longish carbon resistor (which is well within specs) and tied to a different physical spot on the same signal, plus some other things like a broken solder lug on the band switch nearby where the resistors are soldered to, from which I make an assumption it was at some point repaired. The remaining flexes are dead on, probably wire-wound.
Some old carbon ones are remarkably close to the nominal value.



Here is a question I have:

(the link is here)

http://www.nostalgiaair.org/PagesByModel...001472.pdf

Does anyone know if the C6 quad capacitor is paper or mica? It looks like a paper (a large block of four caps) but the values and the place it is used imply possible mica type.
I am not sure this will be changed (this is oscillator circuit grid feedback so it is low volts, no problems with possible shorting) and the values seem to be not too far from the nominal, but would like to know for my own peace of mind.

[fields 100]

The dreaded moment has come: I have just put on my table the AK808A I bought last summer.
Wow, what a serious animal.


There are some that are well cracked, the black ones, that carry the filament voltage, red (same signal, coming from the power transformer), a couple of beige ones.

I just finished my #206. If yours is an animal, mine was Godzilla in comparison( my other thread has a photo)..All the same,the transformer in my set, when put apart, had those great soldering lugs which made the cracked wires replacement super easy. Concerning the grid wires coming from the top of aluminum cans one must be very careful removing the coils. I had to drill out the mounting studs the get the coils out and replace the grid wire. I changed the entire wiring for a good measure. It may look good undisturbed, but will crack at the slightest movement.The naked stranded wire wrapped around the grid  wire - some sort of shielding - one end is grounded, and the wire is coiled around the grid wire until it is terminated close to the grid cap.

[morzh]

It is not shielding, it is a small capacitor. As a shield it is practically nonexistent at these (or any) frequencies. It would make for a few pF capacitance.

[fields 100]

It is not shielding, it is a small capacitor. As a shield it is practically nonexistent at these (or any) frequencies. It would make for a few pF capacitance.

Hmm... Still think it is a shield. But that's OK. Whatever you say...

http://www.atwaterkent.info/TechData/Ima...09_005.gif

[morzh]

This is not a radio, this is a freakin' nightmare. Cauchemar.
I'm a goin'to take a photo of me table covered with debris and the wire....oh Lordy....what have I brought upon meself.....this monstrosity is gonna take as much time all my radios put together.
Woe is me!

[fields 100]

This is not a radio, this is a freakin' nightmare. Cauchemar.
I'm a goin'to take a photo of me table covered with debris and the wire....oh Lordy....what have I brought upon meself.....this monstrosity is gonna take as much time all my radios put together.

I told you so... Yet, it is getting hand on experience.
[ltr]C'est pourquoi je suis tellement content pour vous. Bonne chance![/ltr]

[thirtiesradio]

A.K. radios are the worst...at least to restore. I had restored two of them, and not learning my lesson I bought and restored a 112S.
Never again. I spent way too much time replacing the bad wiring. Strange thing is the set played when I bought it, even with a lot of the wiring missing much of it's insulation. You can see some of the insulation missing on the grid wires. Here's the chassis.

[fields 100]

A.K. radios are the worst...at least to restore. I had restored two of them, and not learning my lesson I bought and restored a 112S.
Never again. I spent way too much time replacing the bad wiring. Strange thing is the set played when I bought it, even with a lot of the wiring missing much of it's insulation. You can see some of the insulation missing on the grid wires. Here's the chassis.

Same with mine. It was working with a bad wiring. Nightmarish stuff replacing all of it. But great performers.

[Arran]

 I'm being punished right now on a post war Electrohome radio a guy talked me into restoring. I like most Electrohome sets but the guys who designed this thing must have been Limeys. It's probably one of the worst radios I've had to work on in terms of design, deep chassis (for 1948 ), narrow from back to front, terminal strips mounted bellow the tube sockets on the inside of the back apron, weird routing of resistors and capacitor leads just to ground them to the chassis, and just for fun the mounted the output transformer under the chassis right bellow the power transformer.  I only have an area of about 2-1/2'' x 2-1/2'' to access the bottom of the 6SA7 tube socket, which is made worse by the fact that Dominion Electrohome used some of the worst octal tube sockets known to man, even compared to other wafer sockets.
I've already broken off two of the terminals from the 6SA7 tube socket thanks to the awkward angles I have to work with, such that I'm thinking of putting a new socket in rather then trying to repair it again. The antenna coil got hit by lightening an replaced with a ferrite bar antenna, which never would have worked, so I had to find another coil. The speaker cables and the power cord are rock hard and cracking. Most of the resistors were either badly drifted or completely open. This set clearly had a high number of hours on it and was nearly run into the ground, if it had not belonged to this fellow's father I would have told him to scrap it by now. The Rogers Ten-60 wasn't this bad, and it had hand wired circuit boards connected to rubber wires!!!
Regards
Arran

[fields 100]

When I was finishing mine, I put garbage can next to my chair and had some thoughts...Guess it got scared, for it went on immediately and had great reception on all bands straight away. I forgave it.. The early cathedrals (80, 82,84) were much better built and easy to work on. Almost no rubber wiring.

[thirtiesradio]

When I was finishing mine, I put garbage can next to my chair and had some thoughts...Guess it got scared, for it went on immediately and had great reception on all bands straight away. I forgave it.. The early cathedrals (80, 82,84) were much better built and easy to work on. Almost no rubber wiring.

[thirtiesradio]

 I'm being punished right now on a post war Electrohome radio a guy talked me into restoring. I like most Electrohome sets but the guys who designed this thing must have been Limeys. It's probably one of the worst radios I've had to work on in terms of design, deep chassis (for 1948 ), narrow from back to front, terminal strips mounted bellow the tube sockets on the inside of the back apron, weird routing of resistors and capacitor leads just to ground them to the chassis, and just for fun the mounted the output transformer under the chassis right bellow the power transformer.  I only have an area of about 2-1/2'' x 2-1/2'' to access the bottom of the 6SA7 tube socket, which is made worse by the fact that Dominion Electrohome used some of the worst octal tube sockets known to man, even compared to other wafer sockets.
I've already broken off two of the terminals from the 6SA7 tube socket thanks to the awkward angles I have to work with, such that I'm thinking of putting a new socket in rather then trying to repair it again. The antenna coil got hit by lightening an replaced with a ferrite bar antenna, which never would have worked, so I had to find another coil. The speaker cables and the power cord are rock hard and cracking. Most of the resistors were either badly drifted or completely open. This set clearly had a high number of hours on it and was nearly run into the ground, if it had not belonged to this fellow's father I would have told him to scrap it by now. The Rogers Ten-60 wasn't this bad, and it had hand wired circuit boards connected to rubber wires!!!
Regards
Arran

Sounds like a real job to do that one
I've restored a couple "deep chassis" 1930's RCA sets that were nightmares. The 140 was one that comes to mind. Hard to get to anything in that set.

[Arran]

 I haven't worked on an RCA-Victor 140 as yet, but I can tell you one thing for sure since I have worked on some G.E sets that were very similar like the J-82 and S-42A, the quality of the parts was much better, you have to really try to wreck a tube socket in one of those. Those are much along the lines of that Rogers Ten-60 I have, only the service info is much more detailed in the RCA or G.E folders, and the hand wired circuit boards actually have tie points attached to the board rather then relying on resistors with spade terminals to use as tie points. The main thing with any of those 1931-33 RCA and G.E sets is that you need to plan ahead, you have to document everything that is not in the service folder, remove everything in the way to get access to the underside of the chassis, and then start rebuilding everything in layers. The Electrohome chassis isn't anywhere near as deep as a Victor 140, but unlike a 140 everything is either soldered to the chassis or riveted in place, so it is not easily removed.
 If it were not for that one tube socket I would be 90% finished by now, and it is not because I am too rough with it either, it's just poorly designed, much like the A.K coil cans that you and Mike are having to deal with. I just can't get over how a company that normally made sets that were so cleanly laid out produced such a crap pile as these. Most Electrohomes are like RCA sets from the same era, they used large spacious chassis where you can get at everything, they still had the crappy sockets but at least you could get enough access to the tie points to avoid bending them and snapping them off.
 It's sort of hard to explain why the tube sockets are poorly designed, but they used wafer sockets which are so so anyhow, but the real issue is in the design of the terminals. The tie points or terminals are lets say 1/4'' wide, but for some reason the manufacturer cut a 1/16'' notch in either side near the base of each terminal. So 1/4'' of brass, minus 1/16''+1/16'' leaves you with basically a terminal that is only 1/8'' across at it's weakest point, but to make it more fun the cuts created a weak spot so if you even look at the terminal the wrong way it will snap off, whomever designed these things clearly did not understand the concept of metal fatigue. 
Regards
Arran