Yesterday I bought a 7" Admiral electrostatic TV in a Bakelite case for $55 at a local antique shop. The set is complete except the knobs are missing as well as the channel escutcheon is also missing The chassis was loose in the cabinet as well. The foam rubber mask for the CRT was a pile of trash mixed in with the considerable dust inside.

The Good: I tested the 7JP4 in the resident Tele-Tone and it is as good as new. Nice and bright and sharp. The set comes up without smoke and has B+ and try's to make High Voltage.

The Bad: It appears all the original capacitors are still in place including the HV cap's. A flat metal plate that mounts the tuner is missing.

The Ugly: Now i'm obligated to restore this little Television so I'm looking for the appropriate knobs and escutcheon and about to order capacitors. Seems this set deserves a re-stuff.

Anybody have parts they would sell/trade?

I believe these little Admiral sets are fairly common and seem to be decent sets. They have a real power transformer

Jim

They also work really well, arguably the very best of all the 7" sets that were built.

I would expect these are still common enough that someone has parted out a set with a cabinet that was broken beyond hope.

I restored one for a friend a few years ago and was rewarded with a razor-sharp picture. Odds are the high-value resistors will have to be replaced.

I started the process as time permitted.

I still need the knobs and tuner escutcheon if any of you have parts you would be willing to sell.

I have enough HV caps and I thought I would re-stuff the originals.

Most of the paper caps are those tan colored molded types known to be leaky (my Solar CB is ready to go).

The local electronics store ha a box of polarized cheater cords and if they have the mating chassis mount I will put that in as someone has already removed the original.

Jim

Jim-

If you do not find the polarized cord connectors, let me know. I have a source nearby, so I could pick up a few for you if you need them.

I bought one as well this week and I was wondering if anyone might have the schematic available. I also need the correct knobs as mine are missing. I haven't tested it as the power cord is broken and I sold my TV test gear last year as I didn't think I would ever use it. Any help would be appreciated as this is my first TV resto.

Pretty sure the schematic is already scanned and posted to the ETF website.

I got this set working by just replacing the HV capacitors.

I'm sure they all need to go but first things first.

The HV power supply is quite lame, the best it will do is 3 KV which is a dim picture. The feedback clip on the 1B3 is beyond touchy for adjustment. It only oscillates when it is positioned over the bottom ring in the 1B3 tube and even then very touchy. I tried several 1B3's and it only likes the one in there. Tried several 6V6's for no improvement. Havent messed with capacitors yet but the trusty Solar is on the bench, I plan to replace all paper caps.

B+ is 238Volts which is slightly low. I ran it wit B+ supplied by my Heathkit bench supply at about 250V and I get more HV but not up to snuff.

This set is easy to work on and seems well constructed.

Useful test equipment includes B&K 1077B, Solar Capacitor bridge, HV probe plugged into HP counter with a digital volt meter plug in, Heathkit PS-3 bench supply.

Still looking for knobs and escutcheon.

Jim

Does this set have a power transformer? If not then it must be using a voltage doubler power supply. In that case bad electrolytics can cause the B+ to be low. And if it has selenium rectifiers those can cause low B+ too. As for the paper caps, I would replace any in the HV supply first and see if that brings up the HV. Another possibility it that the HV coil has taken on some moisture and the set just needs to run for awhile to dry it out.

The Admiral 7" has a power transformer and 5Y3 rectifier. I would expect that replacing the electrolytics and paper caps will bring the B+ and the HV closer to specs.

Tinkering continues…

This TV is an Admiral model 19A1, there are several variants.

The Voltage chart shows 240 B+ on the filament of the 5Y3 and that is the point they supply the HV oscillator. The B+ with the original caps in place holds at 235 volts so it’s not too far off.

While I’m waiting to get a parts order together I’m going to see if I can get the HV up to around 5 KV.

I have the schematic, and resistors are next, I’m not sure what all draws off the HV string but some of these sets get B+ for the sweep output tubes from the HV supply.

I take the fix-it-as-I-go approach where some folks like to dive in all the way. So I like to see what works and then slowly work my way through the problems until I have eventually replace all the cap anyway but it is more fun my way

I pulled the turret tuner apart and cleaned it up and it is solid on all channels, I even caught the detent roller before it rolled off to the black hole. I have the munting plate for the top about hogged out of a sheet of copper.

Jim

Chris

You mention a source for the cord connector?

Someone has removed the connector on the chassis and the current power cord passes through the hole. The local parts store has a ton of polarized cheater cords so I thought if I could find a chassis mount connector I would go that way.

The 180 K grid to ground resistor on the HV oscillator tube was the culprit for low HV, It had gone wide open. the three caps in the twist-lok can were dragging down the B+ so subbing those out got the HV up to 6,000 volts.

The set gets a very decent picture and nice and bright. Nothing else has been replaced yet except the HV caps.

I will replace all the paper caps as I go but I'm surprised it works as well as it does.

The Bakelite cabinet needs a little touch up and I'm still searching for knobs. Seems like everything you buy now days is missing knobs.

Jim

Jim-

Send me a message here, and I will go check the store. How many connectors do you want?

Chris