I'm trouble shooting a cute little Philco 37-84 cathedral. It has 4 of those "nasty" bakelite capacitor blocks. Apparently a production change substituted a 379DG (grounded) block for a 7762EU (ungrounded) block. At least the schematic parts list shows it should have a 7762EU. I cannot find the 379DG block in Philco Service Manual 289. Can anyone tell me the cap values and which lugs are used? I believe the radio has never been "touched" before.

Thanks. Art

Hi Art,
I thought all of the blocks had 4 numbers on them, along with the letters. Perhaps there is one number that did not get stamped in all the way? It may barely be showing.

It might be a 3793- which would include .015 or twin .015 caps.

On the diagram, it shows part 20 (the 7762 block) with only the .001 being grounded. Those caps should be .001 and .015
If you can see, there might be only one thin wire coming out of the block to the ground point.

The common point would be where the 10K and the 240K resistor are attached to the block.

I recapped a model 84 last year and the chassis might be similar. If it is, I can have a look under there for you. I do see the chassis are the same at the area where the 7762 block is installed. Let me know, and I can get photos for you. Or perhaps my set has the 379_DG cap installed.

************THAT WOULD BE GREAT. SEND OFF-GROUP TO ME AT artdrhs at yahoo dot com. THANKS, ART

Gary (and/or others),

Just discovered the broken wire stub in the chassis--pic below. It's coming off the oscillator transformer (lower left corner). Schematic resistor #6 and mica cap #7 are visible on the transformer.

Have any idea where that wire is supposed to connect. I can't see a place for it.

Thanks,
Art

Is there a cross reference that correlates the number stamped on the block to the part number shown on the schematic, i.e. is part 20 on the schematic always a 7762 block?

Maybe soldered to the center tab on the block right next to the wire??
Phil

My local radio buddy thinks it may have gone to the volume control. In my first picture I posted here that wire is wrapped in with those going to the pot. I have a loud hum after replacing the electrolytics.
Art

I found a 3793DG in a Philco 37-62 across the AC line input that shows 2 .015MFD caps in it. Can't tell you what the wiring connections are though. Maybe your missing that last number on the block. Just a guess.

Had an email picture from a friend who has the same radio. Guess what...that wire is cut off on his 37-84 also! And it plays!!

It's probably "part" no. 3: "Capacitor-capacity obtained by twisting end of two leads together." See http://www.nostalgiaair.org/PagesByModel/225/M0013225.pdf

Steve Chambers

Steve is right, that 'stub' is the Gimmick Capacitor. I wrapped it about 2x around th lead going to the volume control. It gives a little feedback to the circuit previous stage.

I will send off a couple of photos so you can compare the two. I'll have to pull the chassis in a few minutes. I don't mind helping out, you guys have always helped me

Will be back in a few.

Oh, I did take a photo of the Gimmick cap wrapped around the wire when I redid the chassis.

Well, I'll be.
Thanks.
I'll put it back like I found it.
Art

Hi Art,
My head was spinning a little too. Here are 3 shots just for fun.
What I found was
Part 20 on the parts list (37-84) shows your 7762EU. Wired in correctly

Part 28 on part list (37-84) calls for another 7762EU .015 dual grounded to mounting bolt.
One side of line is filtered, the other cap goes to the HV CT.

In 'reality', I have a 3793DG for part 28 ( the dual .015) Just as you do.
The model 84 parts list calls for a 3793AD (.015 x 2)

Could the part 28 on your set, that was changed (factory) used the .015 for the line filter, and the .001 for the CT connection?

Then they decided to change the whole block to a 3793DG with dual .015 for the line and the CT.

Just to note, both of these caps in question had been marked with a different number, then a line was ground through the number. A new number was added to the other side of the block.

As far as I know, my set had never been touched either since coming from the factory.

Here's the photos, I have to go and assemble the radio again before a cat starts to investigate it
Take care!

Thanks for your effort Gary. One thing is certain about old radios; NOTHING is certain.
Art

You got that right Art.
The factory did some odd things.
I just recapped a small Coronado Jewel. There were 3 terminal lugs in there that were never hit with the soldering iron. A couple of resistors or wire leads threaded through the holes, that's it. Saved photos of that.

Happy to help out Art, take care.

I'm guessing old radio assembly jobs were pretty boring. Hot factories w/no air conditioning, especially in the 1930s. Running a big hot soldering iron all day wasn't the most enjoybale task I'm sure @ $.35 to $.40/hr. Easy to miss a radio or two. Work 6 days a week for $25+ or -. But..... it was a job during the depression. I found radio production wages in a book in my alma mater's library a few years ago. Metal lathe operators made ALOT more...maybe even $.75 to $.80/hr. Interesting read.