Admiral 24A12 restoration
 

What a surprise - I scored another Admiral set :banana:
They must have been very popular in Chicago back in the late 40s. I find more of this brand than any other.

This is the sister set to the very similar looking 20X122 which has a gold bezel and single chassis while this set has a white bezel and a split chassis.

This is the first set I've picked up from an active smoker.
I didn't think much of it when I picked it up, but after I got it home I really noticed that both it and I stunk :yuck:

He had it running when I came to pick it up - ugh. I switch it over to channel 6 (low power analog station) and heard some nice audio - even without an antenna, but no picture.
The price was right though so I brought it home.
http://farm3.static.flickr.com/2716/...ff13d56487.jpg http://farm5.static.flickr.com/4041/...af520b6ed4.jpg
http://farm5.static.flickr.com/4045/...940db2ca_b.jpg

First, I cleaned the knobs. One, it's easy. Two, I just picked up some Simichrome and was curious to try it. Man, this stuff is incredible!
http://farm3.static.flickr.com/2762/...68f04c42bb.jpg http://farm5.static.flickr.com/4013/...da95b62dd0.jpg

Only one scratch in the cabinet that I've noticed.
http://farm3.static.flickr.com/2770/...5aa1d84746.jpg

I've only done a little cleaning, but the bakelite 'grain' looks really nice.
http://farm5.static.flickr.com/4059/...a9cb0b11_b.jpg

It appears that someone worked on this set in the mid-80s based on the date codes on the caps.
http://farm3.static.flickr.com/2763/...646abe99_b.jpg http://farm5.static.flickr.com/4063/...c2e74004_b.jpg

The lower chassis is a bit rusty.
http://farm5.static.flickr.com/4071/...216d1b4d_b.jpg

Made in good old Chicago
http://farm5.static.flickr.com/4034/...beebcb30_b.jpg

I put some felt pads on the bottom so it's easier to slide around and protect my floors.
http://farm5.static.flickr.com/4071/...1cd89e1f_b.jpg

The 10BP4 tested nearly dead at first. I let it cook for a few hours at 7 volts and it improved until it was just touching the green. I may try rejuvinating once I get the set running.
http://farm5.static.flickr.com/4002/...59680ac67e.jpg

Here are a couple videos of me checking it out and trying to get it running.
The 1B3 appears to be bad and the 1/4 amp fuse was blown. I replaced the 6BG6, 1B3 and fuse and tried to power it up.
The fuse blew again. I need to do some more checking now. I sure hope the flyback is OK!

Any ideas?


Admiral 24A12 part 1
Admiral 24A12 part 2

Nice set, sir! I'm sure you'll have it playing fine in no time.

I would check the grid of the HOT for bias, maybe a leaky coupling cap.

I've got it running
 

Yep, the culprit was some bad caps around the HOT. Specifically, the multi-section electrolytic C422. I haven't replaced any of the other electrolytics yet or even touched the lower chassis, but I will. It's running pretty darn well right now and I can't wait to see how much better it might get with a full recap.

I also discovered several dubious repairs like these two 0.001 MFD caps in the sync inv. / disc. circuit. I have no idea what type of cap is correct or what the voltage rating should be.
I just went with what I had on hand - 630 V poly caps. Does anyone have a parts list for a 20A1 chassis that does specify these caps?
http://farm3.static.flickr.com/2739/...a96855ae_b.jpg


Also the original 8.2K power resistor in the HV cage is open and was bypassed at some point with the smaller green one. That's a shame because I really like that old style ceramic resistor.
I'll try to dig up one that looks better and mount it properly.
http://farm5.static.flickr.com/4050/...81a8889f_b.jpg

There's an interesting metal hoop under the HV rectifier tube. I wonder what that's for?
http://farm5.static.flickr.com/4030/...edd44ab7_b.jpg

Here's the first picture I got using rabbit ears and local lower power channel 6 using a 5AXP4 test CRT.
http://farm3.static.flickr.com/2608/...7e0691de_b.jpg

And here it is using the 10BP4 :banana: The CRT is brighter than I was expected based on the weak test reading. I guess time will tell.
http://farm5.static.flickr.com/4025/...036f80d1_b.jpg

http://farm5.static.flickr.com/4054/...d4c9df92_b.jpg

http://farm5.static.flickr.com/4064/...aa0d5574_b.jpg

It's nice to have an easy restoration for a change :)

I'm in love...An' in awe ! (grin) Those Bakelite Admirals are just SOOOOOO purdy...

Gorgeous. I should look for an Admiral like that. Plenty of elbow room under the chassis, and a nice turret tuner.

Hard to believe you have such a nice picture with practically no work. I seem to end up with dogs of the other kind; weeks of slaving and scratching my head, and I finally get a picture looking that good . . . almost!

Phil

Great find! it is nice to get an easy one once in a while!

"There's an interesting metal hoop under the HV rectifier tube. I wonder what that's for?"

If it is connected to the high voltage, I suspect that it serves as a (anti) Corona Ring, to reduce the possibility of corona and arcs between the sharp points under the tube socket (such as cut off wires and socket pins) and the chassis.

jr

That makers sense. Yes, it's connected to the HV - also the metal ring around the tube socket.

Thanks. I've found about 20 caps in this set that have 80s date codes. So I'm not the first to restore it. I'll probably end up replacing all of those though. Hard to believe the mid 80s was 25 years ago now!

Speaking of dogs, the previous owner had two dogs. So in addition to being stinky from cigarette smoke it's full of dog hair!

I bet I'll spend more time cleaning it than soldering :D

Very nice pictures! Amazingly sharp. I noticed that set used a 6X5 in the power supply section. Those have been known to short and take out a power transformer. Here is a whole discussion about the early vs. the later version of the tube, the later "X" plate design usually deemed more rugged. One good idea is noted: provide a separate 6.3 volt transformer for the 6X5 heater, so that if it does short, it won't take out the power transformer. Some just replace the tube with a couple of diodes.

http://antiqueradios.com/forums/view...&highlight=6x5

I put up a couple more videos showing the first video images using the 5AXP4 and 10BP4.

Part 3: Recapping and using a 5AXP4

Part 4: Using the 10BP4

I've heard that the single 20X1 chassis from 1948 performs better, and am curious to put that to the test. Here's a portion of the schematic for one.

It doesn't use a sync. discriminator like this set from 1949 does. I would think using a discriminator is a superior design :scratch2:

http://farm5.static.flickr.com/4049/...68471494_b.jpg

wow that looks nice! great finding one that required so little to get going

http://www.wa2ise.com/radios/admtvbb8.jpg

Mine (Model 24R12) actually worked before the recap. This back in 2000. Here it is above, after a recap anyway, with the game on. These sets seemed to have been well engineered and tough to kill. The weakest spot seemed to be the door that hides the controls between the channel and volume knobs.

Nice set :thmbsp:
A guy in Nebraska tried to talk me into buying that same model set and trust that it would survive shipping. I learned my lesson after destroying a similar bakelite set and turned him down.

I've heard that Admirals are hard to kill as well. Almost temps me to try powering up a couple I've haven't gotten around to yet :scratch2:

Yes, they almost always are missing that door. I only have one set that has it's original door and even that one is cracked :tears:

That plays impressive for a CRT that was reading basically dead. Never thought about letting one cook like that,, Will try that in the future. Nice score!!

Thanks for the reminder. You guys warned me about that tube when I picked up my Halicrafters too.

I was flipping through the production changes and discovered that Admiral added a fuse on the power supply on later runs.
They also suggest that when servicing this set to retrofit a fuse in if it's not already there.

I think I may go the diode route since it's easily reversable :scratch2:

I dug a couple 6X5s out of my Admiral TVs. I wonder if this stacked design is any more reliable :scratch2:

http://www.bobandersen.com/images/misc/admiral6x5.jpg

I was surprised to discover that my 24C16 Admiral uses the same chassis!

http://farm4.static.flickr.com/3567/...0eba29b4dd.jpg

So, I order up parts for both sets and will recap them at the same time :yes:
The 24C16 is all original so I don't think I'd have the same luck if I tried powering it up :no:

I have both the lower chassis up on the workbench and am stripping the rust and rebuilding them. Normally, I woudln;t go to these lengths, but these are really easy to take apart and reassemble.
I did find a couple fired wax caps on the amp down there so I bet this set will sound even better after the recap.
I've already repainted the transformer and polished the tube shields over on the left.
http://farm3.static.flickr.com/2684/...24966434_b.jpg

The caps I have on hand are a little too big to fit in the old cans. I did a little searching and found a line of skinny caps at Mouser that will with room to spare :)
I got a nice pile of orange drops too :D
http://farm5.static.flickr.com/4035/...4bdfc91c_b.jpg

If you go the diode route, you can leave the 6X5 in its socket "for pretty" and just disconnect the socket. The power xfrmr will have a little better time of it with one fewer heater to heat.

Good idea. Perhaps I should do that for the 5U4 tube as well.

If I'm reading the tube data right, it looks like there's a 25 volt drop for every 100mA drawn. That means I should use a 250 ohm resistor in series with the diodes I think :scratch2:

Just about done
 

I've finish restoring the lower power supply + audio amp chassis. Here it is with an unrestored chassis from another set in the background.
I removed the rust from the chassis, choke and audio xfrmrs and buffed them with a non-metallic pad and WD-40. I stripped the power transformer shell and repainted it with black enamel paint. The electrolytics were restuffed and the caps below replaced. A couple out of spec resistors were replaced too.
http://farm3.static.flickr.com/2739/...6f63119c_b.jpg

I'm just about done recapping and replacing out of spec resistors in the top chassis too. Only a few old replacements I left in place because they tested OK.
http://farm5.static.flickr.com/4065/...9d07485a_b.jpg

Here's the new power resistor in the HV cage. It's a little shorter than the original so I used a wooden spacer.
http://farm5.static.flickr.com/4060/...65acf0b1_b.jpg

Only one issue remains.
If I tune for the best picture, the audio is very weak. If I tune for the best sound, I have a lousy picture.
I haven't touched the RF/IF states yet. Maybe it's just a weak tube or a bias resistor is off ?

Otherwise, it's playing just fine. BTW Those earlier pictures look sharper because they were still frames - this is live motion.
http://farm5.static.flickr.com/4034/...fde4cd22_b.jpg

That power supply looks amazing! John

Another perfect job! That power supply looks better than new.

Thank guys. If you're wondering about that one black screw head - well I think those engineers meant for it to not come out. The screw head was pinched. Probably to prevent someone like me from loosening the core up to much and having all the laminated plates come apart :)

Any ideas about the video and audio being out of whack? Several other sets seem to suffer from the same problem. Maybe it an alignment issue or maybe my converter box is driving it too hard? I'll try my BT agile modulator tomorrow.

Hopefully it's the converter box. The RF from mine is horrible. It even acts that way with a modern TV. Using a BT modulator makes a world of difference for me.

Otherwise it could be an alignment issue. Though it seems like that's not too common. I was surprised that after having to rewind a video IF transformer in my set that I didn't have to align it. It seems to work at the quessed position of the core. I expected it to be more critical than that.

John

Nice job on that power supply.

Gee what a surprise!
Here's that very set he tried to convince me would survive shipping just fine. It was destroyed in shipping and now he's selling the remains.
I told him not to try it :no: :tears:

http://cgi.ebay.com/Bakelite-Admiral...mZ250567121991

And after all that, I see he still has UPS listed as the shipping option. No thanks!

I'll ship a small portable, but that is all. I've hardly ever heard of something like this working out well.

Even that does not assure safe delivery... This little (12-13lb) Sony KV-5000 arrived at my house yesterday, with a broken handle, a cracked circuit board around the power plug, and the yoke shoved way back (which makes for a small "roundie" picture and rainbow effect). With a little glue, solder and adjustment, the set is pretty much ok, with a little purity issue near the right side.

So far, I have had good luck with Sony Watchmans, and nothing larger.

jr

First rate work and thanks for the great pics, very interesting.

I got mine about 12 years ago, and my dim memory says it was shipped by a trucking company, and well wrapped in bubble pack and corrugated cardboard box. With the chassis packed separately. It arrived in fine shape. And so far movers haven't fumbled it, after a few moves.
http://www.wa2ise.com/radios/admtvbbf.jpg

I could use the back, and a new clear faceplate (mine has a scratch). But I don't have enough room to keep the extra chassis, and $50 + $75 shipping is a bit pricey.

Hopefully he'll keep dropping that price. Or maybe you can ask him to sell just the parts you need ?

I did have one set shipped successfully and I did the same - cabinet and chassis in separate boxes well packed. Even so, I'd be leery of trying it again.

One of these days I'm going to move to a bigger place and it just so happens the collector I bought this set from owns a moving company :)
I'll feel better with my sets in his hands than some random outfit from the phone book.

Thanks - glad you're enjoying it. I have about 20 more sets to restore so lots more to come in 2010. Here's a few more about this set.


I was lucky to get a back with this set. It's a little bent and rusty, and someone cut a slot for the optional internal antenna.
I don't have that antenna though - wonder what happened to it.
http://farm3.static.flickr.com/2752/...67fb448565.jpg


That's the optional internal antenna in the background from another set. Next is the back from my 20X122 with the factory cut slot. Finally, is the back that came with this set.
http://farm5.static.flickr.com/4060/...f78c7a36_b.jpg


This set didn't come with the antenna, but I have one from another set. It was only commended for those in a strong signal area. Translation - it didn't work very well ;)
http://farm3.static.flickr.com/2750/...ee4d13b3_b.jpg

http://farm5.static.flickr.com/4039/...b8777f0d_b.jpg

I was digging through my tubes and came across these two guys - solid state replacements for a 5U4. I don't know if I'll bother trying them though. Is 30 year old silicon any more reliable than a 60 year old tube :scratch2:
http://farm5.static.flickr.com/4038/...97d5c97993.jpg

Come to think about it, but I wonder how Admiral got those Bakelite TV sets from their factory to the TV shops and to customers' homes? :scratch2:

Dunno, but the ETF has a great photo showing how strong they supposedly were.


http://www.earlytelevision.org/image...sci_9-49-1.jpg

http://www.earlytelevision.org/admiral_19a11.html

While re-installing the chassis I notices they had been rubber mounted. My wooden cabinet Admirals are not. I'm guessing it's because bakelite is more dense :scratch2:

They're not in the greatest shape so I've been working on replacing them. I used some plumbing washers for the lower chassis.
http://farm3.static.flickr.com/2730/...0004351d_b.jpg

I'm going to try to salvage the upper chassis mounts with some metal -> rubber cement.
http://farm3.static.flickr.com/2773/...fa2358a8_b.jpg

http://farm3.static.flickr.com/2762/...c14aa329_b.jpg

New 10FP4 CRT
 

Although this CRT is working OK now, I doubt it will for long. So I've been keeping my eyes open for a replacement. I was quite surprised to see a NOS 10FP4 on eBay last week. I really hope I wasn't bidding against one of you guys :para:

Here's it is in it's original box.
http://farm3.static.flickr.com/2770/...33cc668e_b.jpg

Did GE have exclusive rights to this tube ?
http://farm5.static.flickr.com/4046/...fa56bef908.jpg

http://farm3.static.flickr.com/2719/...350d7677_b.jpg

It tests really good :thmbsp:
http://farm5.static.flickr.com/4029/...5fd71ce6_b.jpg


Here are a couple pics from my initial tests. It's hard to photograph the difference but to my eyes this tube is brighter and clearer.
Maybe it's not kosher to use a 10FP4 in this set but I'm not complaining.
http://farm5.static.flickr.com/4070/...ff85c75e_b.jpg

http://farm3.static.flickr.com/2780/...fabd8000_b.jpg

Here's a video I shot while trying out this CRT. http://www.youtube.com/watch?v=ua47ZsW9L4s

Very awesome restoration!
Here is Cora's latest find, She rescued this pretty Admiral from the Fairview, trash compactor. She took it apart and after a good cleaning and a few new tubes she is as good as new. The paint is still show room new. She does get hot after a hour or so, so we only play her for short periods. I do not think she was ever watched at all from the condition she was in.
http://img6.imageshack.us/img6/1900/admirall.jpg

Thanks. I got a new antenna a few days ago. Now it's the spitting image of Eric's :D

http://farm3.static.flickr.com/2778/...33cff1414a.jpg

Simichrome polish on bakelite
 

I've been using a Simichrome a lot lately on brass and cadmium. It's been working so well I ordered up a big can of the stuff.
Then I got to thinking, how would it work on bakelite :scratch2:

I had previously used a little Novus #2 and Glayzit on the top. Here's what that looked like.
http://farm4.static.flickr.com/3552/...4f8bfde1_b.jpg

Here it is after a little Simichrome. I've only done the top, front edge and around the screen so far.
http://farm4.static.flickr.com/3411/...3dba0cbd_b.jpg

Here it is after a couple more rounds of polishing.
http://farm4.static.flickr.com/3142/...bde0e6a9_b.jpg

http://farm5.static.flickr.com/4016/...af942782b8.jpg
I won't kid you, it takes a lot of elbow grease. I spent about two hours on the Admiral and my arm is shot. Doing the sides and grill will take even more effort, but I think the results are worth it.