[David]

During WW II someone might have fixed the set with what they had in stock. Look at page 14 of the PDF. David  https://philcoradio.com/phorum/showthrea...0#pid78180

[7chip7]

My 37-61 has 2 Philco cap blocks in it, I know how the the primary transformer bypass Block goes, but I am a bit confused about the other block (3793 DG). The schematic does not show how this block is wired in, I know lug 1 goes to ground and also know  2 resisters go to lug 2 but that is as far as I can get. Is there a schematic for this radio that shows the block wiring? Se attached photo
Chip

[RodB]

Hello Chip,

I looked at the schematic and pictorial for your 37-61 and couldn't find a second bakelite block. Also, there isn't one listed in the parts list. So let's see if we can identify the components attached to the block terminals. Can you identify the values of the attached resistors and which terminals of the block they are soldered to? How about the other end of the resistors? Are there any other wires soldered to the block terminals? If so, where do they go and what components are they attached to? Can you show us a picture of the block and surrounding area?

[Radioroslyn]

So what do the resistors connect to?

[7chip7]

Check the 2 attached photos, the cap block in question is item 46 as shown in the chassis view and listed in the parts list.
Chip

[Radioroslyn]

46 is the one connected to the ac line. #21 & 41 are just using the end terminal as a ground connection.

[RodB]

Part 46 in the pictorial doesn't have any resistors connected to lug 2. As Terry said, there's two components connected to lug 1 which is a ground terminal. There should be a wire from lug 2 and 3, one to the transformer primary and the other to the power on/off switch. In addition, one of the power cord wires should be connected to lug 2 and the other to 3. Neither the schematic nor the pictorial show a second block. If your radio has a second block then someone has added it and discovering what components are attached will help to determine how and where it is wired.

[7chip7]

Here are 2 photos of the chassis , one photo shows my original , and the other is another 37-61,  you can plainly see both blocks. There are resistors  and other wires connected to block 46,  (top of  photo), the AC line block is bottom of photo.  both blocks have caps inside, I rebuilt both blocks. The schematic shows how the ac line hooks to the bottom block, but does not show the top block wiring.  
Chip

[Radioroslyn]

I'm thinking it's the .03 #40 hiding inside the block. Check the pn of the block to find it's value. It's engraved on it's side. #40 is part of the tone control circuit.

[7chip7]

I rebuilt block 46 and it calls for twin .015 caps. The .03  #40 is tubular as shown in the pictorial .  I replaced #40 with a new one.   I guess these old radios went through so many changes, it gets confusing sometimes.  I should have labeled all the wires I took off in the power supply chassis, I thought the schematic could be used, but the schematic does not show block #46. I am not an expert, but I have restored  quite a few radios in my day.  Any way, I only have 3 more wires left to hook up, so I should be able to come up with something, the smoke test will tell the tale.
I appreciate the response and help.
Chip

[Radioroslyn]

Just for grins check the resistance between pin 3 of the 6F6 and the terminal closest to the sidewall of the chassis, the one w/2 wires attached of the unknown block. If it shows a short it's #40 .03. It's kinda makes sense, one wire goes to pin 3 of the 6F6 and the other goes to the spkr cable to the opt. The cap is connected across the two end terminals the middle is a tie point.

The give a way is the #41 30-4112 (.008mfd) that's connected to it. It seems to be the only one in the set...

[RodB]

It appears to me that block 46 has been relocated to the low position in the photo and the mystery block is in the upper spot. The power line is connected to the lower block.

The 20K and 51K voltage divider is connected to the upper block. Looking at the schematic, that point has part 16 (0.1 mfd) supplying screen voltage to two tubes. Part 16 is probably in the unknown block. I checked earlier for a service bulletin but couldn't find one. It looks like this configuration has been there awhile, can't explain why it's this way. You'll have to check the wiring to verify that point runs to the screen grids and the wiring for the other lug.

[7chip7]

Part 16 is external, (right side of the chassis view. Parts 40 and 41 are external (left side of chassis view) I already put new ones in.  I put in new resistors in also. Block 46  (upper left of chassis view), I put 2 new  .015 caps in that one. I put two new  ..015 caps in the ac line block (bottom view in the photos). I wired everything according to the schematic and did a quick smoke test with only the rectifier tube inserted just to see if I have DC on the plates and screens, everything looked normal. Now I need to do the speaker wiring and then I will put all tubes in and go for the smoke test again . I will let ya know what the results are later today . Thanks for the help with this head scratchier,  its these sort of things that makes the history of radio interesting.
Chip

[7chip7]

I took the speaker out for testing, I checked the dc resistance of the field coil (1200 ohms), audio transformer (Pri 422 ohms) (sec .8 ohms) and the voice coil seems to be OK. I am no expert when in comes to these old  type speakers with field coils. I  attached a photo  which I labeled with what I think is the wire colors for each of the three terminals . Am I correct with the colors and also are these the only 3 wires I need to connect to the radio? 
Chip

[Radioroslyn]

Green - pin 3 of the 6F6. White -pin 4 of 6F6. Green/white -Goes to the filament of the rectifier, either pin. For the speaker to work yes.