More about my new (old) 1954 Philco...

[Raddion]

Originally Posted by bgadow

The capacitors won't cost you too much. Justradios.com or radiodaze.com are good choices. Don't worry about the ceramic discs, just the electrolytics and the "paper" caps (probably Sprague Black Beauties in that set). You could power it up with just new filter caps but it wouldn't work right, and a couple of those BB caps could blow up while you are testing it (not as big a deal as it sounds!) Might be good to do it in sections, trying it after each one. That will help you localize any mistakes you might make, and also teach you what each section does.

Thanks Bryan wrote it down and I will check those sites after I get a list ready.

Man I pulled one of the chassis sections tonight, uh wow there are more than a few capacitors involved in this overhaul.... I can DO it..... I think....


Raddion

[Raddion]

Here's a couple pics from tonight's disassembly session:

[Raddion]

Ah...

[Raddion]

Another...

[Phil Nelson]

Ugh. You have to wonder why they made the thing so darned cramped when they had a big, roomy cabinet to spread out in. Perhaps the chassis was used in more than one cabinet.

Sometimes you need to remove (or half-remove) a few other parts to reach those buried farther down. In tricky spots where I don't trust my memory, I take closeup photos or draw a sketch of the various connections.

Working in stages is good advice. I begin with the electrolytics in the power supply, since all else depends on them. As soon as you can get some semblance of a screen image, it's helpful to play the set every now and then, to make sure you're not going backwards.

Take your time, and it will get done eventually. You may also want to check things off on the schematic and parts list as you replace 'em, to help keep everything straight.

Phil Nelson

[jr_tech]

Originally Posted by Phil Nelson

Ugh. You have to wonder why they made the thing so darned cramped when they had a big, roomy cabinet to spread out in. Perhaps the chassis was used in more than one cabinet.

Indeed that was the case... Over the years, minor variations of the "split chassis" design were used for sets ranging in size from 14" inch rectangular to 16 inch round to 17, 21 and 24 inch rectangular (both table and console models). I am not sure if a UHF tuner would have fit between the two chassis in the 14 inch model, but in all the other models there was plenty of room for the UHF tuner, if needed.

jr

[dieseljeep]

Originally Posted by jr_tech

Indeed that was the case... Over the years, minor variations of the "split chassis" design were used for sets ranging in size from 14" inch rectangular to 16 inch round to 17, 21 and 24 inch rectangular (both table and console models). I am not sure if a UHF tuner would have fit between the two chassis in the 14 inch model, but in all the other models there was plenty of room for the UHF tuner, if needed.

jr

I don't think Philco made a 14" set that late. The split chassis design was one of Philco's dark secrets. It seems it was more expensive to build that way. That was the last year for the splits.
The 1955 model year it was back to the single chassis and tube rectifier.

[Raddion]

Originally Posted by Phil Nelson

Ugh. You have to wonder why they made the thing so darned cramped when they had a big, roomy cabinet to spread out in. Perhaps the chassis was used in more than one cabinet.

Sometimes you need to remove (or half-remove) a few other parts to reach those buried farther down. In tricky spots where I don't trust my memory, I take closeup photos or draw a sketch of the various connections.

Working in stages is good advice. I begin with the electrolytics in the power supply, since all else depends on them. As soon as you can get some semblance of a screen image, it's helpful to play the set every now and then, to make sure you're not going backwards.

Take your time, and it will get done eventually. You may also want to check things off on the schematic and parts list as you replace 'em, to help keep everything straight.

Phil Nelson

Yes, I also use pics and sketches when I take apart transmissions and engines etc... I will yank the power supply side of the chassis tonight and start with that as you suggested.

[old_coot88]

Originally Posted by Phil Nelson

Working in stages is good advice. I begin with the electrolytics in the power supply, since all else depends on them.

In addition to the electrolytics, there is one non-electrolytic that should always be replaced routinely before power-up. That's the coupling cap going to the grid (G1) of the Hor.output tube. Any leakage in this cap will cause the tube and flyback system to pull excessive current.
G1 will be pin 5 (assuming the tube is 6BQ6 or 'DQ6).

[N2IXK]

Be careful with that yellowish powdery deposit on the insides of the metal chassis. The chassis was most likely cadmium plated, and the yellow stuff is finely powdered cadmium "rust", such as cadmium oxide or cadmium sulfide.

Cadmium compounds are quite toxic. You don't want to inhale the stuff, or otherwise ingest it.

[Raddion]

Originally Posted by N2IXK

Be careful with that yellowish powdery deposit on the insides of the metal chassis. The chassis was most likely cadmium plated, and the yellow stuff is finely powdered cadmium "rust", such as cadmium oxide or cadmium sulfide.

Cadmium compounds are quite toxic. You don't want to inhale the stuff, or otherwise ingest it.

I was wondering about that yellowish dust! Will it be difficult to get off of there, yikes....

[Phil Nelson]

Originally Posted by Raddion

I was wondering about that yellowish dust! Will it be difficult to get off of there, yikes....

It cleans off easily with a liquid cleanser and paper towels. Wear rubber gloves and don't lick the stuff, and you will be OK. This is oxidation of the cadmium plating, so your goal is just to clean up the dusty stuff, not remove the plating or make it shine like a mirror (which it never did, anyway).

If a chassis is very greasy & dirty underneath, you can stand it on its side on some newspaper and clean with a spray bottle of cleanser (I like isopropyl alcohol) and a soft brush. Work from top to bottom and dab up the excess with paper towels. Alcohol is nice because it evaporates without leaving a residue.

Phil Nelson