Trying to find these smd resistors to buy, power supply side mosfets melted down on this amp due to stray wire (all gate resistors on PS side all measure 10Ohm/spec) and the gate resistors on the output side are reading all wonky but mosfets are all good, SMD104 are reading between 33kOhm-100kOhm (spec value is 100kOhm which only a very few are reading as that) and 1x SMD100 isn’t reading at all, so I’m thinking I need to replace the ones not reading right while I’m replacing power supply mosfets with new IRF3205. Any help with part numbers on the DigiKey.com site would be great, they look to measure 3mmx1mm each. New to amp repair so I apologize for my newbness, I posted about this amp in Amp Power Supply page. Also should the resistors measure their value and that’s that or can anything effect their reading? I was reading, if I remember correctly, that they should measure their spec value within maybe a 5% tolerance and if they don’t they are bad. Got my spec values from resistor calculator online via markings on the SMD. Any help on this would be great, ty!
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The resistors may be fine, in-circuit measurements are always at the mercy of other components in the circuit such as the MOSFETs, you may be seeing leakage in the MOSFET gates. Resistors like this don't tend to get damaged until severely overheated (pcb scorched). MOSFETs on the other hand are easily damaged if the power supply blew-up.
Standard SMD resistor sizes are 0603, 0805, 1206, in imperial (hundredths of an inch). 3x1mm doesn't exist
to my knowledge, perhaps you measured poorly? 0805 is 0.08" x 0.05" or 2x1.2mm, 1206 is 3x1.5mm
Standard SMD resistor sizes are 0603, 0805, 1206, in imperial (hundredths of an inch). 3x1mm doesn't exist
to my knowledge, perhaps you measured poorly? 0805 is 0.08" x 0.05" or 2x1.2mm, 1206 is 3x1.5mm
Ahhh ok, ty. I’ve been trying to find out if other nearby components effected their measurements, so ty bro that helps TONS, although they may all be good I still think the one 100 that gives off NO reading might be bad, lol. And yes I did measure poorly as I didn’t want to get to close and I didn’t use my calipers, it must be a 1206, which also helps a lot, ty for the insight, really appreciate it.