RCA T-120 in failure mode!

[Ralph S]

The set's repaired. After pondering the symptoms of the failure, it became obvious that something had to be dead-shorting half of the horizontal windings. Either it was a wiring or insulation problem or the resonant cap had shorted out. The answer was the latter. The pictures below tell the story. The 56 pf cap is C-169 in the original RCA schematic and unnumbered in the Photofacts schematic. The manufacturer is EL-Menco (made in USA) and is obviously 62 years old. Its resistance is .3 ohms and it looks slightly burned along the bottom row of dots. That's what caused the keystone and crimped the HV down to ~5kv. Luckily I've got a very good supply of new picofarad caps and the results of the replacement show in the off-the-air photo. Thanks to all for their suggestions.