Silvertone 8106

[Giulio Maiocco]

Doug, sorry to not being able to help you out about your width issue, but one thing in your message popped out to my eyes: the 2 adjustments on the horizontal coil are NOT for fine/coarse adjustment!

This is the typical synchroguide horizontal oscillator and, for proper operation, it should be set in the following way: first, you set the horizontal hold pot at half of it's travel, then you short out C48 (the .01uF capacitor in parallel with the horizontal waveform coil) and, with the upper slug, you should sync the image on the screen. Then you remove the short on C48 and, with an oscilloscope connected at the junction of the 2 coils, you should obtain a combined waveform composed of a sawtooth and a sinewave, just like this one: http://www.rfcafe.com/references/ele...cs-world-3.jpg. You should pay attention that the "tip" and the "shoulder" of the sine part of this waveform are at the same height.
If this particular oscillator is not properly aligned, it could cause every kind of strange behaviour in a TV set.

If you already knew that, then I apologize having stated the obvious

Cheers

Giulio

Edit1: I rechecked the schematic, your TV doesn't have a horizontal hold pot, so disregard this 1st step
Edit2: The place to put the 'scope probe is called "G" on the schematic you provided. If, after tweaking the slugs, you still have instability, you should check the waveforms coming from the sync separator, if these have the correct shape and amplitude, then keep in mind that all the mica capacitors in the hor AFC/oscillator circuit are suspect, as these are under lot of electrical stress and can definitely fail. These capacitors MUST be perfect and NO leakage!
Note3: Your R36 (or R38?), the 8,2K is the screen grid dropper for the Hor. output tube. Changing it's value affects the frequency because the B+ voltage for the hor oscillator is derived from the B+ boosted. Changing the resistor does in fact have an effect on the B+ boosted source because it lowers or raises the power the 12AV5 gives out.