When there are multiple questions and/or multiple people helping, you need to ask questions in a way that makes it very clear what you're referring to. Either quote or take the time to ask the question more clearly.
Ok, sorry about that, I posted my last question without reloading the page first. So do I remove the 640's and 9640's showing the low readings? input trans. ok?
Remove the ones that you were referring to that corresponded to the pieces of text that I copied and pasted from your post.
ok, i'm not sure if you included text you didn't mean to coming from the previous test result in the line but I think I have it understood. Next time I will be sure to include the #'s on the circuit board. It would've made it a whole lot simpler. Please excuse my inexperience.
yes that's what I was referring to. I think I'm going to edit post #15 with the corresponding circuit numbers.
To simplify...
Remove the transistors that read significantly less than 20 ohms from leg 1 to leg 2 or leg 1 to leg 3.
Remove the transistors that read significantly less than 20 ohms from leg 1 to leg 2 or leg 1 to leg 3.
Ok, thank you very much. I knew when I was logging the test like that it wasn't the right way so to speak. I am going to remove the 9640 at Q251 and the 640 at Q215 from the output sides. Now, i remove those 2 and test the others in the rows?
Already answered that one huh? They call me simple pat. I was hoping to change that here. Already ruined that chance!
I removed Q251. Q252 reads 2.06 across legs2+3 and climbs slow. Q253 reads 2.08 and climbs slow. Q254 reads 2.10 climbs slow. Q255 2.5 and climbs faster, Q256 reads same as Q255.
Removed Q215. Q216 reads 3.0 and climbs. Q214 reads 2.1 and climbs slow. Q213 reads 2.8 climbs slow. Q212 reads 2.8 climbs slow. Q211 reads 2.8 climbs slow.
All were checked on legs 2+3.
out of circuit
Q125 legs 1+3=1.3ohms. 1+2=1.3ohms. 2+3=.3
Q251 legs 1+3=.2ohms. 1+2=.2ohms. 2+3=.1ohms
Q125 legs 1+3=1.3ohms. 1+2=1.3ohms. 2+3=.3
Q251 legs 1+3=.2ohms. 1+2=.2ohms. 2+3=.1ohms
They are defective. If you read anything other than OL (or whatever your meter reads with the probes not touching anything) between leg 1 and the other legs, the FET is defective.
Just so were on the same page, the power supply fets are Q17-Q24 (IRF3205's) right? Legs 2+3 on those were starting low around .3ohms but were climbing very slow. Then the meter would jump to 10ohms and drop very slow. I dont know what that means besides cheap meter.
As long as you don't get a constant low resistance, they're likely OK.
Reassemble the amp and clamp all transistors tightly to the heatsink. Insert a 15 amp fuse in the B+ line and see it the amp will produce clean audio.
Reassemble the amp and clamp all transistors tightly to the heatsink. Insert a 15 amp fuse in the B+ line and see it the amp will produce clean audio.
Oh boy! Wish me luck, gonna be a couple of days probably. Thanks for your help! I'll be back.
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