Thank you...I've never ordered samples before, how does that work? I've checked the Motorola website but I haven't found a place to order samples...Won't they think my request looks more like a shopping list than an evaluation request?
Let me know if it works. I just got some more transistors from Mouser yesterday to pop in , hopefully this will be the last time I take this thing apart. I didn't really find any shorts but a few had a bit low hfe, should be around 30 as per NTE manual, I was getting 24-25, si I thought since it was apart replace those and check every other one. Hopefully have it back together in the next day or so.
I believe that's the designation for one of the Analog Modules, of which there are 2 per channel: AM1 - AM4. These were basically unobtainium until deafbykhorns designed replacements and made them available to the community...I didn't realize there was an AM5 in ARC amps, so somebody more knowledgeable will need to chime in and fill in that gap.
thank you for your answer
I don’t see AM5 in the diagram
but regarding AM3 and AM4 I saw information
Tell me, is the circuit according to which transistors are used in the to126 package - is it commercial?
or not?
Well after spending hours installing some new transistors where are few were suspicious transistors, I have 6.01 volts on the left channel and -50.2 on the right. I have run out of ideas. There were no shorts indicated when I had the 4 boards off. Any ideas?
Bad cap? Or diode in backwards? Or you stuffed the AM2 wrong, the silkscreen is the tab side
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Those are all new, wish it was that easy. The AM1 or AM2 is not causing it.
Also mine didn't have any .47uf cap across the elec. cap C32
Also mine didn't have any .47uf cap across the elec. cap C32
No everything checks out, and when I made the boards I made sure the 340 transistors were positioned the correct way. No idea what is going on
I just unsoldered leads so I have access to 4 driver boards. Before that I checked and I have the +50, -50v and -75 and +75 volts.
Weired with the predriver board unhooked now the right channel is showing +50 volts on the output terminals, before with the driver board wired it was -50.
I have attached 2 pix see if anyone can spot anything. I checked the diodes they are ok, I replaced them when I redid the 4 resistor driver boards with 1N4007.
Weired with the predriver board unhooked now the right channel is showing +50 volts on the output terminals, before with the driver board wired it was -50.
I have attached 2 pix see if anyone can spot anything. I checked the diodes they are ok, I replaced them when I redid the 4 resistor driver boards with 1N4007.
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Yes, those transistors can only fit one way; if they get put in backwards (B and E flipped) then the screw holes won't line up properly. About the only thing that can be messed up is swapping the NPN for PNP, or vice versa...I did note that some of those transistors aren't original, did you do that?