Remove the suspect PCB off the heatsink and re-flow the solder joints around C2, Q3, and that general area. Also the big resistors.
Will do. Thanks.
But R4 is connected to the the bias point at Q1....and you measure 16v at R4?
Yes
Then it must be a bad connection else you would have a voltage drop of 6V over the R4.....then it will be hot......
R4 is probably cold at the non working amp and a little bit warmer at the working amp.....
Reflowed everything. Tested with speaker. I got nothing. Maybe not the prettiest soldering.
Try again but this time reflow soldering of all Mosfets.
Good luck
Reflowed everything. Tested with speaker. I got nothing. Maybe not the prettiest soldering.
lousy reflow
what's your soldering setup?
I love Dynaudios ..... small ones .... but I hate one thing with small speakers - when listening on low volume , everything is just ........ smaller.
that's why I generally prefer big spks
I respectfully disagree, maybe this is going a bit offtopic (and I’ll drop it after this post) but I love the precision of small speakers and simple 2 way systems. Big speakers are often suffering from unwanted resonances.
Anyway, love my George!
lousy reflow
what's your soldering setup?
Soldering station with temp control, helping hands/alligator clips, shaky hands and I think I need bifocals now. Lol
Reflowed everything. Tested with speaker. I got nothing. Maybe not the prettiest soldering.
It’s not clear to see from your pics but everything sticking through the board seems pretty long, especially top left two points. Are you sure you’re not shorting anything to the heatsink?
Dan
It’s not clear to see from your pics but everything sticking through the board seems pretty long, especially top left two points. Are you sure you’re not shorting anything to the heatsink?
Dan
I thought of that....last couple of tests have been a quick flip on of the amp without being attached to heatsinks to eliminate that being the issue. So, that isn't the issue.
...small speakers and simple 2 way systems...
I have a bunch of small speakers i really like, but they are all 1-way. Definitely something to be said for no XO to get in the way.
dave
This one looks suspect need some proper rework.Reflowed everything..... maybe not the prettiest soldering.
Maybe the solder tip temperature is too low or too high?
Remember to give first some heat for a few seconds and apply solder after for short ~2 s
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This one looks suspect need some proper rework.
Maybe the solder tip temperature is too low or too high?
Remember to give first some heat for a few seconds and apply solder after for short ~2 s
Ok, I'll see what I can do...
Ok, I'll see what I can do...
This one on the left is OK try all soldering point look like this be ideal.
PCB always in flat horizontal position if You work on components soldering.
Attachments
Could You show on the photo(s) what the PCB's looks now ?I've reflowed the board about 5 times now. Light still comes on. No sound.
Do You reflowed all mosfets as well ?
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