Part of the "barn beasts" eBay score. I decided to work on it first. First time I've run across a 16LP4 roundie. The tube is mammoth compared to a 10BP4 or even a 12LP4. I'm doing this one because I would like to settle the question of whether or not a rejuvenated tube sucks or not. The other barn beasts have CRTs that test well. This one had completely zero emission. I thought perhaps the neck socket had a bad wire so some of the pins weren't making contact anymore, because I'd never seen a total zero tube emission before. Even the black-screen 12LP4 from the Admiral from hell scored a 1. After leaving the Beltron on for several minutes and rocking the socket a bit I did notice that the emission went from 0 to maybe 0.1. So maybe the pins were connecting. So I tried the cleaning function. It never lit a light. Figured I was looking at a parts set at this point but I tried the restoring function anyway. Just as advertised, it restored correctly, no surprises, and tested afterwards as nearly NOS. I let it sit a week (from last weekend to this weekend) and it still re-tests 10.0 and ten seconds of "life test". Apparently good as new, unless the Beltron is lying to me. I think this CRT was about as "gone" as gone gets, short of going to air. So it's a good test case.

I started restoring the rest of the set today, to see the tube in action. I will try to run it a lot and see how a back-from-the-dead Beltron restoration holds up.

The chassis is full of Bumblebees, and unfortunately there's only a partial Sams for it. So it might take a while. And I'm debating whether or not to de-solder all the cap leads this time (from another post).

If anyone could ID a Rider's document or another service sheet, I'd appreciate it. The Sams (91A-10) is just a preliminary brief, not a full folder, and it's pretty lacking.

Photos later...

It's in Rider's volume 5. I can mail you photocopies if you PM me with your address. I can get it in the mail tomorrow.

Steve

Philco's of that era are just about the worst to work on in my opinion.

Cram packed full of Bumble Bees and just about anything else Philco had on hand, Loktals, Octals, 7 pin, 9 pin, 5 different brands of caps... :p:

I wonder if they were using up war surplus?

I suspect that they were using war surplus. I have restored late 1940s Philco radios that contained the following:
1. All Lockals
2. Loctals and octals mixed.
3. Loctals, octals and 7 pin minatures mixed.

The radios all had the same case style. In the case of the 7 pin minature the chassis hole was sized for a loctal/octal. A special large 7 pin socket was used due to this.

My dad was a TV repairman in the '60s. He always used to say "effin Philcos", but he didn't say it exactly as "Effin", if you know what I mean.

I picked up a Philco 50T1440 a year and a half ago from John's TV in Cleveland, as a throw-in when I got my Zenith Roundie.
http://www.audiokarma.org/forums/attachment.php?attachmentid=27073
I opened it up and had a look, winced a couple of times and put it away. Scrambled mess of every part imaginable. No surprise John didn't want to work on it.

This 50T1632 isn't nearly as bad. Looks attackable anyway.
It has 2 distinct chassis' and separately mounted CRT. Left Chassis is RF/IF and right chassis is Power/Deflection chassis. Divide and conquer.

Still wasn't looking forward to decoding bumblebee stripes. Steve, PM sent.

Thanks!

- Kirk

Very interesting and looking forward to results on this.
Dan

Tube selection at Philco was not based on war surplus, but on several other factors. It had a preferred tubes list for circuit design engineers that evolved from such things as:
1. What was made at Lansdale Tube plant
2. What could be made available in production quantities
3. What was in the pipeline
4. What could be second sourced in event of supply disruption
5. What design support the Lansdale application engineers provided
6. The circuit design engineer's preference
7. What made sense for the application
8. The available technology
9. Effort to limit the number of tubes required for production
10. Cost

Very little was in stock for manufacturing purposes. Virtually everything had to be ordered. Getting material on time was a bigger problem than burning off old stock. Obsolete material was scrapped by the truck load at the end of a production run. Tube suppliers had to gear up well in advance of delivery and maintain a running supply during production. The circuits for the 1950 model year were designed in '47 and '48 so they were based on the materials available at the time.

Tube machinery was set up to make several numbers that were used by the military so conversion was easy, but only temporary. Many of the numbers were reliable and engineers familiar with their use, so they were continued for early TVs.

Surplus government material was sold off by the government, not returned to the suppliers. The government took loads of material and shipped it directly to surplus houses. Suppliers had no reason to make more than the contract called for. Extras were lost profits.

Thanks Don, you had to come in here and muck up our perfectly good theories about Philco's parts selection with a bunch of facts. :D

Just kidding of course, doesn't make them any easier to work on though. :no:


Tube selection at Philco was not based on war surplus, but on several other factors. It had a preferred tubes list for circuit design engineers that evolved from such things as:
1. What was made at Lansdale Tube plant
2. What could be made available in production quantities
3. What was in the pipeline
4. What could be second sourced in event of supply disruption
5. What design support the Lansdale application engineers provided
6. The circuit design engineer's preference
7. What made sense for the application
8. The available technology
9. Effort to limit the number of tubes required for production
10. Cost

The radios that I worked(all with the same case style-I am not sure if they were all from the same year) had the following tube lineups for the output and rectifier tubes.
Output Tubes:
35A5, 35L6, and 35B5.
Rectfier tubes:
35Z5, 35Y4.

The other tubes were lockals (of the same number) in all of the sets. The radios are of the late 1940s vintage with the knobs on the top of the set.

Steve K - The Riders documents arrived today. Excellent, thanks!

This 50T-1632 looks like a normal TV of circa 1950. Miniature tubes in the RF/IF strip, octals in the sweep and HV. No Loctals in this one. Except for all the bumblebees, it looks like a quality set.

My dad was a TV repairman in the '60s. He always used to say "effin Philcos", but he didn't say it exactly as "Effin", if you know what I mean.

I picked up a Philco 50T1440 a year and a half ago from John's TV in Cleveland, as a throw-in when I got my Zenith Roundie.
http://www.audiokarma.org/forums/attachment.php?attachmentid=27073
I opened it up and had a look, winced a couple of times and put it away. Scrambled mess of every part imaginable. No surprise John didn't want to work on it.

This 50T1632 isn't nearly as bad. Looks attackable anyway.
It has 2 distinct chassis' and separately mounted CRT. Left Chassis is RF/IF and right chassis is Power/Deflection chassis. Divide and conquer.

Still wasn't looking forward to decoding bumblebee stripes. Steve, PM sent.

Thanks!

- Kirk
Does John often have sets for sale?

I visited John one time only, in the fall of '06, so it's hard for me to speak for him. At that time he had dozens of excellent TVs for sale, but I only went prepared for my Zenith. I spent most of my gas money to get the Philco and then coasted the last ten miles home on fumes. If I had planned, I probably would have come home with 2 or 3 more. Just didn't bring funds.

He also brought 20 or so TVs to the ETF in Columbus last year. If it worked out for him, I would imagine he might be there this year too. Again, I'm not speaking for him. You can search this forum for his address and phone number. It's a retail store front, public welcome. If I lived as close as you do, I'd visit regularly.

I haven't had much time to do TV work. My "paying" job has been an 8-day-a-week crisis for most of a year now. But I was able to plug in the soldering gun this evening. Here's the recap of the power-supply half-chassis.
http://www.audiokarma.org/forums/attachment.php?attachmentid=82960&d=1205632914

Eleven Bungle-Bees, 2 Micamolds, 3 distinct electrolytics and one combo (triple) electrolytic. To my dismay, all of the "paper" caps were bumblebees except for the two micamolds, and those micamolds were (both) the only .022mfd caps! The 022 bumbles are the ones that get 50 bucks a pop on that ePay place. Not squat if they're micamolds. The remaining bumbles were too big or too small. Too bad.

Well half the set can probably stand a powerup. I probably won't get to the left chassis for awhile, but progress is progress. I sure would like to see that 16LP4 light up.