[Jim Dutridge]

Who was the evil genius that designed this layout? I thought the Zenith Transoceanics were a nightmare to work on but this..WOW!

[Image: https://i248.photobucket.com/albums/gg18...f5h7oh.jpg]

[Image: http://i248.photobucket.com/albums/gg187...b5meoq.jpg]

Not to mention the rubber wiring, GOOD GRIEF!!!

[Phlogiston]

All I see is hours of FUN!!

[tbone]

I wonder what the people who built these things thought? Probably left work every day with a migraine!

[morzh]

you sissies.....(no Russ, your attitude is just right)

[Arran]

The post war Philco chassis like the 46-1201 are bad enough, but at least those used vinyl or cloth wire rather then the rubber/gutta percha stuff so you don't have to rewire them (usually). I think that Philco must have hired some more sadists as engineers after David Grimes left the company, modular chassis just were not tough enough, so lets make them shallow and narrow instead.
Regards
Arran

[morzh]

In their defense, the long term properties of gutta-percha weren't known at the time, plus even if they were, the radios weren't supposed to live that long anyway.

[Arran]

Mike;
  I am not so certain about that, if it was unknown then why did some companies use cloth covered pushback wire, or cloth and rubber wire, verses the straight rubber/gutta percha covered stuff back in the early 1930s? Also why did most manufacturers, with the exception of Brand Z, switch to using vinyl covered wire after the war? Regardless of the wire used many of those Philco chassis from the 1940s are still cramped like an inverted sardine can, why they were made that way I don't know, there wouldn't be much advantage in it other then saving some steel, certainly not in labour.
Regards
Arran

[amptramp]

New film caps to replace the wax paper ones will be smaller, so at least you have that going for you.  The rubber disease looks pretty dire.

[morzh]

New film caps to replace the wax paper ones will be smaller, so at least you have that going for you. 

Unless you decide on re-stuffing....

[Jim Dutridge]

Heres another gottcha. The 3rd IF transformer does not match what Riders and the Philco 1941 Yearbook show. There is only 1 capacitor in the can and that is 37A. B and C are not there. There is a wire that is wrapped around the wire going to the plate of the 2nd IF amp 7B7 and it goes to chassis.

[Jim Dutridge]

I just got my service package from Chuck yesterday and the enlarged schematic helps me see things better. So much that I discovered an error in the under chassis view which shows the component placing. Where they show the antenna transformer #9 is incorrect. It actually sits on the top side of the chassis. Where they show it in the picture is actually the oscillator transformer #6. 

Who knows what else I'll find wrong.

[David]

   
Some info from Beitman.

[Jim Dutridge]

I asked this over on ARF and I will ask here. Opinions are being requested. Filter capacitors are both 20Mfd. The service information calls for 120 volts across the input cap and 90 volts across the output cap. I have 33Mfd @160 volt which would fit nicely under the chassis and i have 22Mfd @450 volt that are rather large and would be a bear to try and fit. The floor is open to ideas. No, the original filter assembly was MIA when I received this.

[morzh]

When I needed to replace the electrolytic in AA5 - type sets, meaning little space underneath, I used aluminum cans.
200V rating is more than enough; originally in Zeniths i saw the 160V ones which I think are also quite enough.

[Jim Dutridge]

No place for an aluminum can. I think the original was a cardboard style.