Dear All:
I have been given Magnavox 20MS3442/17 TV which had vertical deflection problem - top half of the screen was squashed and retrace lines on the top of the screen. The unit is about 9 month old, only parts warranty, so it will be more than $100 to repair...
Not sure about chassis - there is almost unreadable white sticker "32 5
29 56".
Nothing is burnt or physically damaged.
Unfortunately I don't have schematics, but do have overall knowledge how TV works and used to repair TV (20 years ago:-).
I was advised (in another forum) to check/replace C301, C302, C304 and IC301 (output vert. IC). I replaced the capacitors, observed polarity, turn it back on and it is completely dead now.
And the details what I have now:
- fuse is fine;
- C806 has 170V and stays long after I disconnect the power cord;
- LED does NOT illuminate, no flashes even once;
- no clicks, ticks or anything;
- no voltage after T803 (like on D833 against pin 11 of T803)
- Q801 is possibly good (I unsoldered, compared resistance G-S to the spare one, appears same);
- IC802 has 3.5V on 1-2 pins and 4.5 V on 3-4pins.
IC801 is MC44608P40 (8pin) and I do not have a spare. All schematics I have is MC44608P40 datasheet where is an example power supply with opto coupler and power MOSFET - looks similar to what I have.
Help anyone?
And if anybody have the schematics of power supply and deflection to email me - that would be very much appreciated.
Thanks in advance.
Igor