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I've worked on a number of those. If the horizontal output transistor is bad, look for bad connections on the transistor itself and follow the base foil to the driver transformer. It can have connection issues also. If the HOT is bad, the chopper (switch mode) supply has shorted transistors and the .1 om resistor is open. Be careful as the main electrolytic(s) can still be charged and ruin your day. Change the two chopper transistors and the resistor and slowly bring it up on a variac. Check for heating (CAREFULLY, The sink will bite if you get between it and ground) of the chopper transistors. If they get hot look for a burned resistor (1/4 watt) going to the standby supply. Use a magnifying glass and you will see it. It usually is green bodied. I can't remember the value but it is a common color code type resistor and usually enough remains to find it's value out. Once the set is up and running, watch for heating on the HOT and choppers after about three to five minutes. If hot, add heat sinks as some of the generic replacements tend to run hot and fail after about three hours without the added heatsinks. Keep us posted!
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