Philco 48-1000 restoration

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I've had this set on the back burner for a while now. Since several other collectors are working on theirs, I figure it's a good time so we can compare notes.

I had wanted one for years but had no luck until a local collector downsized back in 2020.
It in pretty good condition except for some damage to the right of the screen.
Someone sanded aggressively leaving a depression and no finish. Grr.




Here it is arriving at my place. Deceptively heavy set.


The chassis appears to be 100% original.


Although the Sams service info shows "bumble bee" type caps, mine is loaded with convention paper caps in cardboard tubes.


The CRT, yoke, focus coil and speaker are mounted to the cabinet. I supposed I'll have to unmount them in order to fire up the chassis on the workbench. I expect Philco service centers had test jigs.

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I'll be using some CE Manufacturing twist-loc caps for the three man power supply electrolytics.


Curiously the first cap only has two symbols and values listed on the can even though it is clearly a four section cap?




It is C105 in this diagram. The other two section are used as cathode bypass caps in the sweep circuit.
Also, note C102 is in parallel with C103 in some models. I thought it was an old repair but no, it is factory.




Many, many caps to replace, but at least it is easy to unwrap the leads from the terminal strips.

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I switch to working topside for a bit. The surfaces are coated with a waxy substance to is easily scraped off or dissolved with acetone. Nicotine/tar glaze? Condensed wax and from hot components?


The metal underneath is very clean for the most part.


I removed the three caps next to the power supply and cleaned. I'll be using two CE Manufacturing twist-loc caps.




The middle cap is a smaller diameter type mounted on a phenolic insulator.
I'll just hide a new cap inside the original cardboard sleeve.

[Yamamaya42]

Is that a Radio Flyer I see? :O

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It sure is. Had it as a kid in the 70s, but not sure how old it is.

Here's that odd cap. Four sections wired up but only two marked on the can. Neither value is what the service info calls for.

[kvflyer]

I think that the stuff on the chassis is wax as you have noted. And acetone is my friend here too! I just have to be careful around painted surfaces.

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Yes, multiple passed with acetone do the trick. Also, I've been hearing about fiber cleaning brushes for a while and decided to finally give them a try.
They are working fairly well but I think a slightly stiffer bristle would work better on this particular project.



I removed the big filter choke and brushed some new flack black paint on the power transformer.
Then created a star stencil using the original as a template and recreated the white star stamp.

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Just about done with the cleaning. I'll hit the rusted, pitted areas with some Bondo glazing compound filler and brush on some silver, epoxy appliance paint.


The tuner has been lubricated and rotates nicely. Slowly cleaning up all the contacts.


Here's a look inside the HV box. Philco used their own flyback design rather than use the RCA design.

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The power interlock puzzled me for a bit. The pin spacing is wider than usual, and it is polarized even though it is a cold chassis set.
Luckily, it is the same style Zenith used and I had a spare from some recent projects.


Pulled the rectifiers and exercised the power switch a few times to clear it out but nothing. Traced out the wiring and discovered there is a safety interlock in the yoke plug. I bypassed that and viola! Nice to see the tubes light up.
Now, keep in mind I still have the rectifiers out as there is still much work to be done underneath.

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Used some Bondo glazing compound on the rust pits and brushed on a little silver paint. Also toned down that white star on the power transformer by rubbing a little black paint over it.
Sure, it's all overkill but I'm having fun.

[Electronic M]

Enough makes used the Zenith - Philco style interlock that I have no less than 2 service cords for it... One is a normal small pin cord with the Zenith porthole connector added in line, the other is a cheater cord that jumpers between the back cord and and chassis, has a switch box to configure which male pins are energized, and gives a couple of outlets for test gear...

[bandersen]

Good to know. I'll keep an eye out for one. Luckily, I do have the original back and power interlock. It just needs a new line cord.


CRT and yoke assembly has been removed in preparation for a workbench power up.
Now I can finally get those loose bits of screen bezel gasket out of there.