02-08-2018, 01:02 AM
Alignment
With the all the caps replaced it's ready for alignment. I generally rely on the Rider's books 'Aligning Philco Receivers'. I have the paper editions, but they're also available online:
https://archive.org/details/AligningPhilcoReceiversV1
https://archive.org/details/AligningPhilcoReceiversV2
In fact the official Philco service bulletin for the 112 (#101 in the case of this model with 47 tubes) doesn't even include alignment instructions:
I guess not many service people had the right equipment when the 112 was released?
Actually there is another service bulletin (#60) titled 'Adjusting Model 112' that might have that - but I don't have that bulletin in any case.
The process went smoothly and it plays well.
[Image: https://farm5.staticflickr.com/4743/4009...90e2_z.jpg]
Speaker Rewire
The speaker cable has definitely seen better days. A good bit of the insulation was deteriorated near the plug. At the start I temporarily painted that with liquid electrical tape.
[Image: https://farm5.staticflickr.com/4741/2521...f780_z.jpg] [Image: https://farm5.staticflickr.com/4629/3919...7bb9_z.jpg]
But the time has come to do come up with a more permanent fix. EDIT: See Ron's much better solution below - it turns out it is *not* necessary to drill out the transformer rivets. Sadly replacing the wires means drilling out the rivets on both the plug end as well as the output transformer on the speaker. The transformer's terminals are underneath the transformer - no way to access them without removing the transformer first.
[Image: https://farm5.staticflickr.com/4656/2627...8f90_z.jpg] [Image: https://farm5.staticflickr.com/4624/2836...6c00_z.jpg]
So what color should the new wire be?
The original colors of the wires have all faded to to an insipid yellowish-brown color...or have they? Actually there's unfaded bits of wire under both the output transformer and inside the plug.
[Image: https://farm5.staticflickr.com/4605/4014...335c_z.jpg] [Image: https://farm5.staticflickr.com/4654/3943...f5f1_z.jpg]
As far as I can tell the wires were originally:
Each wire was a total of 21.5" in length.
Plug end was stripped to 3/4".
Speaker end was stripped to ~1/2"
Brown thread used to hold wires together. Located at 2" from plug end, 1.25" from speaker end.
[Image: https://farm5.staticflickr.com/4770/3943...9489_z.jpg] [Image: https://farm5.staticflickr.com/4619/4014...8983_z.jpg]
I really don't like removing rivets because I have yet to find a way to redo them in a way that looks clean and original. Hopefully someday I'll have a better way but for now I'm replacing them with machine screws.
I used 4-40 x 3/8" machine screws for holding together the plug and 8-32 x 1/4" machine screws for remounting the output transformer.
[Image: https://farm5.staticflickr.com/4662/2527...122e_z.jpg]
[Image: https://farm5.staticflickr.com/4616/2527...9f71_z.jpg]
Now to run the new wires to the speaker. The original rubber grommet was petrified so I replaced it.
[Image: https://farm5.staticflickr.com/4745/2836...ab6b_z.jpg]
All back together:
[Image: https://farm5.staticflickr.com/4610/2836...02ee_z.jpg]
With the all the caps replaced it's ready for alignment. I generally rely on the Rider's books 'Aligning Philco Receivers'. I have the paper editions, but they're also available online:
https://archive.org/details/AligningPhilcoReceiversV1
https://archive.org/details/AligningPhilcoReceiversV2
In fact the official Philco service bulletin for the 112 (#101 in the case of this model with 47 tubes) doesn't even include alignment instructions:
I guess not many service people had the right equipment when the 112 was released?
Actually there is another service bulletin (#60) titled 'Adjusting Model 112' that might have that - but I don't have that bulletin in any case.
The process went smoothly and it plays well.
[Image: https://farm5.staticflickr.com/4743/4009...90e2_z.jpg]
Speaker Rewire
The speaker cable has definitely seen better days. A good bit of the insulation was deteriorated near the plug. At the start I temporarily painted that with liquid electrical tape.
[Image: https://farm5.staticflickr.com/4741/2521...f780_z.jpg] [Image: https://farm5.staticflickr.com/4629/3919...7bb9_z.jpg]
But the time has come to do come up with a more permanent fix. EDIT: See Ron's much better solution below - it turns out it is *not* necessary to drill out the transformer rivets. Sadly replacing the wires means drilling out the rivets on both the plug end as well as the output transformer on the speaker. The transformer's terminals are underneath the transformer - no way to access them without removing the transformer first.
[Image: https://farm5.staticflickr.com/4656/2627...8f90_z.jpg] [Image: https://farm5.staticflickr.com/4624/2836...6c00_z.jpg]
So what color should the new wire be?
The original colors of the wires have all faded to to an insipid yellowish-brown color...or have they? Actually there's unfaded bits of wire under both the output transformer and inside the plug.
[Image: https://farm5.staticflickr.com/4605/4014...335c_z.jpg] [Image: https://farm5.staticflickr.com/4654/3943...f5f1_z.jpg]
As far as I can tell the wires were originally:
- white
- green
- brown
- brown w/ white tracer
Each wire was a total of 21.5" in length.
Plug end was stripped to 3/4".
Speaker end was stripped to ~1/2"
Brown thread used to hold wires together. Located at 2" from plug end, 1.25" from speaker end.
[Image: https://farm5.staticflickr.com/4770/3943...9489_z.jpg] [Image: https://farm5.staticflickr.com/4619/4014...8983_z.jpg]
I really don't like removing rivets because I have yet to find a way to redo them in a way that looks clean and original. Hopefully someday I'll have a better way but for now I'm replacing them with machine screws.
I used 4-40 x 3/8" machine screws for holding together the plug and 8-32 x 1/4" machine screws for remounting the output transformer.
[Image: https://farm5.staticflickr.com/4662/2527...122e_z.jpg]
[Image: https://farm5.staticflickr.com/4616/2527...9f71_z.jpg]
Now to run the new wires to the speaker. The original rubber grommet was petrified so I replaced it.
[Image: https://farm5.staticflickr.com/4745/2836...ab6b_z.jpg]
All back together:
[Image: https://farm5.staticflickr.com/4610/2836...02ee_z.jpg]