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I have got to post this....I had this unit to repair and the mosfets were shorted and blowing the fuse...Changed them, along with the gate zeners and the gate driver chip IR2110...ran for about a half hour...make a loud bang....like a fire cracker going off then the old familiar DC to the speaker sound....shut it down......left it for a few days and went back.......the mosfets tested great, diodes ok,......I did replace the IR2110......checked associated resistors and caps.....found a total of seven electrolytics out of spec...a couple with no capacity at all....thanks to my newly purchased ESR meter......some of the caps had esr of over 60......replaced all of them and fired it back up last night for a couple of hours.....so far so good......will run it again today at a somewhat loud volume but looks like it should be fine....caps replaced were.....C11, C12, C3, C9, C26, C35, and C7......there were five 12K/5W resistors also siliconed to the board and the board is starting to show signs of overheating....I removed these and installed new ones and mounted them off the board slightly to aid in better cooling.....but don't mount them too high as the back panel won't seat properly....Also note...if you have one of these units with a weak sounding horn, C9 develops high esr and affects the high freq....hope this helps somebody out.......
Cheers
Bernie
Cheers
Bernie