[bgadow]

Well, gang, you can see where my spare time has been going lately!

I eventually replaced all the can caps. This was on suspicion that something was dragging down B+ but it wasn't. I'll tell you, I learned a lot while playing with this. I have a bunch of books and old magazine articles that were a big help, and taught me some of the theory behind the circuits involved. I need all the help I can get! What I found was a blurry blob of a picture; focus voltage was only about 1KV with 15KV at the anode; I learned to measure the HV regulator current, which I could not get below about 1.8ma. (should be around .85) An excellent article covered identical symptoms on a rectangular screen Admiral and came up with a bad capacitor. I replaced that with no luck; the article also mentioned to check the resistors, which tested fine. Later I clipped in a substitution box and found one WAS bad, apparently it couldn't take the heat? A new resistor got me good HV & current. (and focus) The next concern came after the set had been running about an hour and I started to hear what I thought was corona inside the HV cage. I could see no sparks, but then noticed bubbling wax near the core of the flyback. I was hearing not corona but the sizzling of the wax.

I hate to admit it but I had never before attempted adjusting horiz. efficiency but I knew I had to have a look. I thought this would be easy as I have a device that plugs in between the tube and the socket for easy measurement of the current. Unfortunately something is out of whack with it, and I really didn't feel like pulling the chassis again to do some unsoldering. (why didn't makers put something on the top of the chassis to make this easier? Next time I will put a terminal strip up top for easy access.) Instead I concocted a device out of an old octal base and socket. Now, the articles I have said to set the regulator current and not worry about the HV, but it was easier to use the HV at this point. But I found I could not get both a good H.O. current and good regulator performance without checking the regulator current. See, I was learning! Both are now pretty much in specs. The H.O. might be slightly high-I'm not sure how accurate my meter is. Should be 215ma but it looks more like 225ma. The flyback is still warmer than I would like; I need to try and recoat it as a lot of the tar had long ago fallen off the bottom. But I suppose that is the effect of high temperature and not the cause. For now I have left off the cover to the cage for best airflow.

I was surprised to find that the color was working fairly well-that was apparent even when the picture was just a blob. Somehow the purity was almost perfect. No automatic degausser in this set, either. I touched it up...another problem is something screwy in the screen controls/normal-setup switch. I can't get a good line. It almost acts like an intermittent. I've cleaned the switch and all the pots with no improvement. I set the bias/grayscale the best I could.

For now I've put it aside-too many other projects demanding my attention. I really enjoy having a challenge like this land in my lap, though.

oldtvman compared the picture from an Admiral to that of a Motorola and looking at it I think it is a fair comparison. Not unpleasant, really, but there is a pastel kind of look to it. I should be able to squeeze a little better performance out of this one with further efforts, but I don't expect to turn it into a Chromacolor!