Philco TV-123 Chassis



Very large and heavy chassis, note the transformer mounted rectifiers typical of Philco radio designs. UHF tuner is mounted to the left of the VHF tuner.


Close up of tuners. UHF tuner is driven by a dial cord from the VHF fine tuner shaft.


Just about all convergence and setup controls are available from the front of the chassis.

High voltage cage uses two 3A2 & one 3A3 tubes. In the upper right corner you can see the HV safety interlock, this shorts the HV to ground when the back of the set is removed.

After finishing the recap job and reinstalling the chassis in the cabinet, I had no HV. Looking into the HV cage I could see the HV rectifier plate glowing a nice bright red, not a good sign. After some troubleshooting I found that all the HV doorknob capacitors are shorted and I've ruined 3 HV rectifiers, luckily they are inexpensive tubes. Disconnecting the HV filter cap, I do have HV as long as I don't run the AC input above about 85V, after that the other caps breakdown. I am in the process of searching for new caps.

After replacing the HV capacitors the high voltage was restored and I have an excellent picture. The only remaining problem is to lock in the color. The reactance tube plate coil which adjusts the 3.58 oscillator to lock to the received color burst is bad. It seems that over the years the coil form has shrunk so that the slug freezes when turned more than 2 turns. I have tried another coil from one of the spare chassis but it did the same, and while trying to free the slug it cracked. Luckily the coil is only one layer of number 42 wire and not exotic, so I am going to get new coil forms and build new coils, as I expect to have the same problem with the second set I am restoring.

The underside of the chassis after recapping, the set is hand wired and not very well.