[MrFixr55]

Hi Stoney D,

First off, Welcome to the Philco Phorum! Please take time to read the "Phorum Rules" and "What not to Post". We are here to have fun (or "phun") and help fix (or phix) your Philco and other radios. Please feel free to navigate, explore, open doors", etc. on the Phorum website to familiarize yourself with the site. "Old Ron's Bar and Grill" is our virtual hangout where general topics such as the weather, what did you fix and "finds and losses". So belly up to the bar, get a virtual brew and shoot the breeze with the gang!

Secondly, congratulations on acquiring a Model 20. Although many were made, this was a pivotal radio for both Philco and the Industry, and a rather good performer. Although Philco was known for storage batteries and "B Battery eliminators", they got into the radio manufacturing business only in 1928 They sold about 300,000 Model 20s in total, and became the#1 radio manufacturer up to WWII, and popularized the "Cathedral" design. The radio had reasonable (about 1.5W) output, a generous sized 8" electrodynamic speaker and "Screen Grid (Tetrode) tubes in the RF and Detector stages.

Do please continue this same thread as you work toward repairing and restoring this radio. This makes it easier for both you and folks (pholks) who respond to your questions, as the history of your radio will all be in the same thread. I own one of these that I have totally recapped, another that I will eventually get to and have repaired 2 others. Several members also have much experience with these sets.

Thirdly, please post your progress and do not be afraid to ask questions; we are very happy to help!
If you look at the "Header" of this site, you will see 2 links that will be very useful. The Philco Gallery has very good photos of all Philcos from the first Philco radios to 1960. The Philco Library has links to service data (official Philco schematics) and various articles and restoration tips from several contributors, including the late Ron Ramirez who founded this site. Do post photos of your progress, questions and photos of the labels that you have questions about. (We do have a section for various labels.)

To make things easier for you, I am posting links from the Phorum that should be helpful to you:
The schematic and service data for your Model 20: https://philcoradio.com/library/download...l.%201.pdf

You may run into several issues while restoring this radio:

Although none of the "caps" (capacitors) are electrolytic, caps can go bad in this 94 year old set and should be replaced. Hear is an an article by Mike (Morzh) on "restuffing" the Bakelite cap blocks:
https://philcoradio.com/library/index.ph...soldering/ It is important to not just "bridge" over a cap, it must be disconnected from the circuit.

Although this is a TRF (Tuned Radio Frequency) set as opposed to a Superheterodyne) and much simpler, Philco sets of this vintage are notorious for the primary of the RF coils that have tube plate current passing through them to "open". Coil condition can easily be determined by ohming from the plate pin on the tube socket to the B+ at Point D on the schematic. Here is an article on rewinding Philco coils:
https://philcoradio.com/library/index.ph...lco-coils/

This set utilizes a "push-pull" output stage. Phase is inverted by an interstage transformer between the '27 first audio and the pair of '71 output tubes. The primary of this transformer is known to "open". Attached is an article on "bridging" transformers:
https://philcoradio.com/library/index.ph...nsformers/ Following the instructions for capacitive coupling of a good interstage transformer greatly improves the fidelity of the radio.

Field coils and transformers on the speaker used in the model 20 have been known to open. See the following article:
https://philcoradio.com/library/index.ph...-21-70-90/

Ther were 2 speaker designs. The earlier one had a very stiff centering device (called a spider). The later one used a spider that looked like one of those adaptors used with 45 RPM records to adopt to the standard spindle used on record players. This speaker sounds much better than the original.

If you look at the links for these topics, you can see where I got them from.

There are several articles on repairing "cathedral" style cabinets such as the Model 20, Model 70, etc. which had similar construction.

Finally, good luck, ask any question, keep us posted and have FUN! (PHUN)