1981 Magnavox with a problem. - Page 12 - Videokarma.org TV - Video

Firebird · #**166** 04-12-2013, 12:01 PM

I will let you know when i get all the parts for the horizontal board and the capacitors for the sound amp. Thanks.

Firebird · #**167** 04-14-2013, 10:59 AM

Replaced the horizontal output transistor again. Picture came back in color. Still have a small line in the middle where it tries to fold. Flickers a little. Waiting on capacitors and other parts to rebuild the horizontal oscillator board.

Bill R · #**168** 04-14-2013, 07:03 PM

Check the components on the retrace board. Some of these parts are safety components, so be sure to use the correct replacement, including that multi lead safety cap. Check the other caps and diodes on that board.

Zenith26kc20 · #**169** 04-16-2013, 01:55 PM

The foldover is usually a problem with a solder connection in the horizontal driver stage or on the flyback itself. These tend to burn off connectors on the flyback to PC board.
Also, these sets were very prone to safety cap (the four lead cap near the horizontal output transistor) failure. Hopefully the end will pop off when it fails, disconnecting the horizontal output transistor and killing high voltage. Also, if the horizontal output transistor is running hot (check the temperature when the set is off or it may be quite a surprise) don't run it too long or it will kill the new transistor.
If the four lead cap is bad, be careful replacing it with a two lead of the same value. Some caps can't handle the load placed on this capacitor and open with catastrophic results. If the new cap gets warm, try another type, not just a different brand but a different composition.

Firebird · #**170** 04-19-2013, 11:17 PM

High output transistor gets too hot. The capacitor that replaced the safety capacitor is rated at .158uf@1600v. It should be .0068uf@1600v. Hard to find. Does anyone have such a capacitor?

Firebird · #**171** 05-19-2013, 11:20 PM

Hey i found it. Let you know if it works soon.

Firebird · #**172** 05-20-2013, 09:29 PM

For some reason seems to be too much voltage. Shouldn't .0068uf 1600v be the same as 6800pf 1600v. Picture is folding severely, when i tried to adjust height flyback arced at back of case.

Firebird · #**173** 08-03-2013, 08:22 PM

Can't seem to find a capacitor to replace the safety capacitor.

Jon A. · #**174** 08-03-2013, 08:56 PM

Those can be replaced with those "orange drop" units that are often spoken of here. I'm not sure of the specs needed though; check the Avanti resto thread for pointers.

Firebird · #**175** 08-29-2013, 06:13 PM

Found a capacitor, turns out it was .0086uf@1600v. Picture still folds in middle. A while back i found a new tripler and replaced it. Occasionally i hear a sizzling but do not see any sparks. Could the new tripler be bad.