[MrFixr55]

Hi Vintage Rocks,

First off, based on the schematic, this radio should be an excellent performer and worth saving!

Below are some voltage checks. However, a standard warning:
This radio employs high voltages, some as high as 700 -800V AC between the rectifier plate connections. If you are not used to working on high voltage electronics, seek the help of experienced persons. Also note that the noise suppression capacitors marked 89, across the power transformer primary can short and render the chassis to be "hot". Remove these NOW. the radio will work without them. Eventually, they should be replaced with the correct Safety Caps.

Check, doublecheck and triple check the wiring. The ability to read schematics will be very helpful here. Use a du\ocument such as the RCA Receiving Tube Manual for the "Pinouts" for the various tubes, particularly the Rectifier and the 2 '42 Audio Output tubes.

Measuring the resistance of the 3 primary terminals of the power transformer will help identify the correct leads. The 2 leads with the greatest resistance between them (about 700 Ohms) go to the plate connection of each of the 2 '42 tubes. The plate connection is to the left of the 2 largest pins (the filament connections) when looking from the underside. The 3rd wire should measure about 350 Ohm between it and either of the other 2 wires. This wire ties to one side of the field coil and is the connection to B+ for the rest of the radio This joins with positive terminal of Filter Cap 77. The remaining field coil connection is to the junction of C78 and the Cathode of the '80 Rectifier.

Start out your voltage checks by checking between any wire to the Output Transformer and ground. You should get between 230 and 250VDC. If zero V, check your power supply for shorted electrolytics, especially the one labeled 77 in the diagram, the 25uF electrolytic. Remember that these are polarized and will short if polarity is reversed. Shut the unit off before burning out the field and recheck wiring.

If the voltage is there, check the speaker voice coil (you will have to disconnect the transformer secondary from the voice coil connection). If the Voice Coil shows open at the terminals, check the flex cables between the terminals and the cone. The constant flexing is a routine cause of dead speakers. Measuring between the center tap of the HV Section of the power transformer at R77 and chassis ground, expect about -15 and -25VDC. If much more (Say 200 - 300V), the resistor R77 is open, but you would not find the speaker field coil to be warm.

Good luck with this set. If you are successful, this should e a great performer. The Audio Stage consists of '42s in push pull with 2 '37 push pull drivers, a "cathodyne" phase inverter and feedback, and is much more sophisticated than many other Philco and other moderate end radios of the time, and should be truly HiFi if a really good output transformer is used. Once you get this working, add a phono / MP3 jack. This will also be a rather mellow guitar amp.