If one shorted it would not be a very good thing. Burn some fusible resistors for sure.And slam a rail.but they won't harm anything
Do these brown resin deposits on the larger solder connections indicate a possible contact / corrosion problem that should be resoldered? Or are they just old resin residue and can be ignored as long as there are no cracks in the solder and I am getting good continuity?
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I ordered some of these 1ohm bias trimmers from eBay.
Are these a good choice or should I be using something of a better quality? If so which ones?
http://www.ebay.com/itm/161106976171?ru=http%3A%2F%2Fwww.ebay.com%2Fsch%2Fi.html%3F_from%3DR40%26_sacat%3D0%26_nkw%3D161106976171%26_rdc%3D1
I replaced all the capacitors and the two bias trimmers. Amp sounds great and all seems to be performing well.
I do have a question/concern about the bias trimmers because the Service Manual says that when in Class A mode they both should read "70mV +-8mV (Idling Current 0.35A)". After I installed the new trimmers and adjusted them to their target spec of 10mV and then switched over to Class A, the highest reading I could get was 19mV on RCH and 23mV on the LCH. These tests were performed with the amp not under load and having warmed up for a few minutes. Am I doing something wrong or is there another problem somewhere with Class A?
I measured the old trimmers before I removed them and they were also at the same mV reading in Class A.
Thats probably as high as it going to get.
I've never seen it go much higher than 20mv. ..... the 40/60/80 never come close to printed values.