Hello ngen33r, I am posting here in your thread to hopefully get some help. I have a RPW-10 that worked great for years and then no longer was working...I unfortunately left the switch in the "auto on" position. I don't use the surround sound system on this TV often, so i do not know how long ago it stopped working...it may have been several months ago! I found the fuse was blown, replaced it and it blew immediately. I removed the plate amp, but I did not see anything obvious in regards to blown components in the power supply. A Google search brought me to this thread and I was on my way! I followed every suggestion in this thread: 1) rebuilt PDC, 2) replaced mosfets, 3) full recap, 4) replaced TH3, and eventually upgrading Q5 to 2N4401 from SOT 23.
Rebuilding the PDC was done based on your schematic in the first post of this thread. However, the values of my original resistors were totally different from those in your schematic---although the board number was exactly the same (660038RA). See pictures below:
Original board:
Rebuilt PDC:
I also replaced the two IRF730 Mosfets with two IRF740 Mosfet transistors. I also replaced TH3 (DSP104) even though there was no damage to it and then I replaced all CAPs with Nichon and Kemet (470uf) 105 C caps except I did not change the two 35V 4.7 non-polar caps at C48 and C53 (I ordered regular polar caps by mistake). In addition to all of the suggestions you made in this thread, I also (6) replaced the two voltage regulators at U4 and U5, (7) replaced the transistor at Q8, and for good measure (9) I changed out all 5 of the output transistors (IRFZ14). The picture below summarizes all of the changes:
Summary of All changes (before changing out Q5):
Now, I am no longer blowing fuses but the amp is still not working. After a short period of being on, the Mosfets really start to heat up...I am not noticing any other components getting warm and there is absolutely no speaker noise. I am now stuck and I am almost tempted to replace the safety capacitors (yellow thingys) and the bridge rectifier. However, I wanted to reach out to you first for some guidance. I have no schematic and I haven't got the slightest clue how to trouble shoot without knowing voltage "test points". Can you please give some advice? I am tempted to throw in the towel and but a new plate amp replacement, but I feel like I am too far into this to quit now...do you have any advice for a hobbyist? Thanks in advance!
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