View Full Version : Predicta Tuning Alignment Problem

05-26-2017, 08:54 PM
Hey gang, I have an issue I need guidance on. I'm working on a Philco Predicta Tandem. I have it pretty well wrapped up, and it's all working well except for the sound. With a broadcast source, I get great video on channel 3, as I should. But, I have to adjust the fine tuning all the way to the stop in order to pick up any sound, and it's distorted a bit. Plus, at the point where I pick up the audio, the video is unstable and easily falls out of sync.

Now, if I turn to channel 2, the audio comes in loud and clear (for channel 3), but no video. I can't get the video and audio to converge in the same spot. I tried new tubes in the tuner, I cleaned the tuner, adjusted the local channel oscillator so I get the best video in the center of the fine tuning range (per SAMS), and I cleaned the fine tuning capacitor. Could I maybe have a faulty oscillator tube? :scratch2:

Any advice is appreciated. Thanks!