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Preset buttons work, dial button soft volume
#1

My Philco A-801 was built for the 1942 Desoto, which was of course not built because of the war, so the set was put into an end table. It's a transformer set, which of course originally it was a battery set. Anyway, I can get good reception and plenty of volume with the preset buttons (tuned into appropriate local signals, of course) but the "dial" button does not work! I tried shooting the sliding contacts with contact cleaner, but to no avail. It gets extremely faint volume. Any ideas?

I recapped it but, I'm using the original electrolytic can, also. It doesn't get hot, so I think the little tin can filled with boric acid will work just fine. There is no hum when the set is on. The guy who rebuilt my 1946 television swears by original electrolytic cans, if they still work.

Damon
St. Louis, MO
#2

Well... the power transformer self destructed today, so no need to answer that question about the soft volume. Icon_sad Anybody got a spare transformer? I don't suppose ANY transformer with a "high voltage" winding and 6v filament winding would work?

Damon
#3

Damon,

I am also working on one of these, and I am also in St. Louis! I just finished re-capping the unit but haven't re-attached the tuner assembly. It hasn't been powered up yet.

My transformer was toasted when I got the set - Ron R. set me up with the winding parameters and it crosses to a Hammond 270FX. You've got to be careful and make sure you get a big enough filament winding to power all 8 tubes in this thing. I got one from RadioDaze - it wasn't cheap, but I'm on a quest now. I put an 8 pin octal plug on it from Gateway Electronics to facilitate easier cabinet assembly.

Here's the details on the transformer-
HV - 550V center tapped (275-0-275) at 150 mA.
Filament - 6.3V at 5A
Filament 2 - 5.0V at 3A (not used)

The filaments add up to 3 amps, so you could conceivably use two transformers- there's plenty of room. I'd use at least a 4A filament transformer.

If you're interested, there's an antique radio club here in St. Louis - http://www.archradioclub.org . We meet once a month and talk about stuff like this, among other things. Check the website and/or email me for more information.

Joe T.
#4

I've seen quite a few posts about this set. I have one that I've never dug into nor fired up. From what I've been able to gather, the power transformers tht Philco used in these sets were under rated, which is unusual for Philco. (Perhaps they bought from Zenith's transformer vendor) But we must also remember that these sets were converted from the Chrysler sets as they were made , with war substitute-grade transformers. Icon_sad

So, when I un-bury mine, I should have a new power transformer near at hand. I've never heard one, but they ought to have terrific audio. Those 8 tube Chrysler sets were one of the best sounding auto sets made from the mid thirties, well into the fifties.
#5

I have a radio phonograph made during WWII using a 42 Chrysler radio, only mine is a Motorola ,after market, I have another Motorola console auto convertion, not sure what kind of car it was desided for, Pontiac maybe?, The one [Chrysler type] I restored plays great ,I have one parts chassie with power transformer ,I believe would work on the Mopar,BILL
#6

The manual tuning on this set is another tuning unit besides the PB tuning. It's a slug tuned setup, independent of the PB tuned circuits You might check the coils in it to see if one might be open. That's what it sounds like. These 8 tube Philco Chrysler sets are hot radios, as well as one of the best sounding auto sets of their day. There are parts sets laying around, I'm sure. This same radio was built for all Chrysler cars from 1941 throoigh 1948.
#7

Ampico66 Wrote:My Philco A-801 was built for the 1942 Desoto, which was of course not built because of the war, so the set was put into an end table. It's a transformer set, which of course originally it was a battery set. Anyway, I can get good reception and plenty of volume with the preset buttons (tuned into appropriate local signals, of course) but the "dial" button does not work! I tried shooting the sliding contacts with contact cleaner, but to no avail. It gets extremely faint volume. Any ideas?

I recapped it but, I'm using the original electrolytic can, also. It doesn't get hot, so I think the little tin can filled with boric acid will work just fine. There is no hum when the set is on. The guy who rebuilt my 1946 television swears by original electrolytic cans, if they still work.

Damon
St. Louis, MO

That original electrolytic condenser should be replaced, by the 1940s the industry had changed over to dry electrolytics but I would not trust one that old. Low volume can be caused by a multitude of defects the first to check would be a wiring error from replacing the paper condensers, the next would be a bad plate resistor on the first audio tube. A misalignment of the IF, RF, antenna and oscillator adjustments can also cause low volume, or a open coil as someone mentioned. I would check the continuity off all of the coils, and check several of the plate resistors in the other stages of the set, a leaky condenser can overload a resistor causing it to drift upward in value or even go open. Oh, and test the tubes as well, someone may have run the set into the ground before putting it in storage.
Best Regards
Arran
#8

Ampico66 Wrote:Well... the power transformer self destructed today, so no need to answer that question about the soft volume. Icon_sad Anybody got a spare transformer? I don't suppose ANY transformer with a "high voltage" winding and 6v filament winding would work?

Damon

Are you certain of that? Did it really burn up? Do you know which winding went out? I would check those electrolytics for shorts, they may be to blame. Here is what I would do, find an appropriate sized transformer from a junker chassis, since it's a set with 6.3 volt tubes that means a scrap chassis from about 1935-65, including radio phonograph units. Count how many tubes it has, and what sort of rectifier, and what voltage the high voltage winding is, if it uses a 6X5 or an 84 then the rectifier doesn't matter. The high voltage winding can vary about 10% plus or minus and it won't make much difference, but get one that is as close as possible.
Best Regards
Arran




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