The emitters of both banks of 6488s should be connected by the 0.1 ohm resistors. If you don't read something very near 0 ohms between the emitter legs of the two banks of 6488s, you need to find the broken connection. It could be that the emitter resistors are open but that should be evident.
all of the emitter resistors measure ~.3ohms between legs. the test i performed was measuring continuity between heat sink and one leg of the emitter resistor. when clamped it shows short, but not clamped open. the 2n6491g's show no short to heat sink clamped or not. For the clamp i am using double side tape(white) from mouser and no signs of shorting.
i stepped away from the xtr 275 for a few days. tonight i clamped both sides and any of what i was measuring earlier is gone. amp works fine now? perhaps i had the clamps reversed and the tooling was slightly different causing a short. Nothing that i can see however. Aww the story of electronics continues.
Thanks Perry.
Thanks Perry.
I realize this is an aging post, but...
AllAroundSound --
Did you ever fix your amp? I acquired the same amp, with similar issues. It looks like someone has poked around inside my amp once before.
Since I can't get a schematic, I was hoping to get some higher quality images from the inside of yours. Maybe together, we can fix both of these.
Can you post better quality pics that show the part numbers on your amp?
I realize that in the power supply are a bunch of NDP7060. Then, there are rectifiers that are FEP16CT and FED16CT.
Aside from that, I need to see all the output transistors. In your picture, I can't see the part numbers and in what sequences the are installed on the board.
Any help would be appreciated.
AllAroundSound --
Did you ever fix your amp? I acquired the same amp, with similar issues. It looks like someone has poked around inside my amp once before.
Since I can't get a schematic, I was hoping to get some higher quality images from the inside of yours. Maybe together, we can fix both of these.
Can you post better quality pics that show the part numbers on your amp?
I realize that in the power supply are a bunch of NDP7060. Then, there are rectifiers that are FEP16CT and FED16CT.
Aside from that, I need to see all the output transistors. In your picture, I can't see the part numbers and in what sequences the are installed on the board.
Any help would be appreciated.
Please don't post in a repair thread that was started by someone else unless you are trying to offer assistance to the original poster.
Click on the red triangle in the lower left corner of your post and ask a moderator to move your post (and any replies to it) to a new thread (my post should be deleted).
If you want to refer to this thread, post a link to it.
Click on the red triangle in the lower left corner of your post and ask a moderator to move your post (and any replies to it) to a new thread (my post should be deleted).
If you want to refer to this thread, post a link to it.
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