no matter what device you use in the repair of the convergence drive the amount of heat produced is calculated by voltage and current = power power consumption by all devices in the circuit add to local heat however heat (too much) is not the problem with these devices in this unit the convergence IC's recieve power from scan derived sources and in most cases the amount of AC proponent in the DC voltage is excessive this produces what is known as dirty power. The source diodes if leaky on the reverse direction (high impedence direction) can lower the source. if leaky in the forward direction can cause the filter (ripple cap) to go bad. Also if the unit is in the northwest or central areas of the USA the lack of humidity in the air can degrade the filter ESR rating by electrolytic evaporation. a simple capacitance meter can not measure the ESR value of a capicitor. common values that lose ESR over time are 100/25 1000/16 1000/25 and 2200/25 also but not related to this topic is the 47/50 and 4.7/25 (rca) a medium or high quality DVM can produce accurate readings of leakage or ripple on the sources by use of the AC voltage scale. Lower priced DVMs just average way to slow to get an accurate reading however if the lower priced DVM reads a slightly higher than normal voltage then most likely its due to AC as AC is about 1.4 x higher on the DC scale than the same DC voltage due to averaging. an oscillascope is best for this process but I havent had use for one in over 18 years. the convergence circuit is best related to a stereo audio output circuit. Each of the 3 guns (CRT deflection yokes) have a single OP amp like input with high current output. Vertical and Horiz drives are altered by "settings" so basically an audio circuit is left/right and convergence is Horiz/Vert just as in audio circuit improper input bias can effect the heat and efficiency of the circuit. CLEAN voltage supplies and accurate "trim" or bounce resistors can lower the temperature slightly. Best over all way to lower operating temperature First use super hync sync compound. Philips made a nice compound. However Mitsubishi has the best. this should be applied very THIN to the contact surface. next find the AC main bridge and locate the standby (pre smps)source use a diode forward series tap (anode to source) to isolate the source any 1N4000 series diode will do. Next add a 12 volt regulator IC 3 pin TO-220 type in series and run the ground (center terminal) back to standby ground. This should be almost all you need the output will now be low current 12 v and ripple should be very low. Adding a filter cap will only increase the current draw on the standby supply. Next use a 2 wire 12v DC fan (CPU type) or only the 2 of 3 wires of a speed detecting type cpu fan Ground and B+ the third wire is a DC offset output indicating speed. You can place a 47K ohm resistor 1/2 wt in series with a LED on the output line and return to standby ground this will cause the led to "Light" up when fan runs. Place the Fan with output direction of air flow "exiting the rear cabinet" in line with "heat" a simple "hand in the box" will tell you where the hot spot is. Please note that these fans do make a slight audible sound. and that if your floor is dirty or dusty most of time ; alot of that will pass thru the TV in the form of carried dust with the new airflow. and lastly no matter what you do to rebuild the convergence circuit properly two things still can cause problems (pin cushion drives from main deflection) and (glyconol "crt coolent" leakage into yoke windings) (or use of silicon to "mount" deflection/convergence yokes on tube necks) in most projo TV's red leaks the most often and was also first to get enzyme growth in fluid. Only after you are certain that the convergence IC's and drives are properly rebuilt do you ever consider removing and inspecting the CRT yokes however if a flashlight in the dark reveals small shiny droplets any where on chassis PCB's or Crt necks during inspection expect a long time consuming costly repair. any one requiring assisstance with any PROJO TV problem can do as any my 23 students have done.. Contact the walking schematics I remember like a book and have seen just about 99.99% of all Projo TVs and their associated failures.

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