Babelfish M25, SissySIT - general building tips and tricks

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Well, finally got back to it. Pulled my non-working board as recommended. Not sure, but I think I might have over heated a part...


One other thing caught my eye there: you might want to cut the leads of the components you soldered closer to the board.

Depending on the length of your stand-offs, you might get some of them shorting to the heat sink otherwise ...


Regards, Claas
 
One other thing caught my eye there: you might want to cut the leads of the components you soldered closer to the board.

Depending on the length of your stand-offs, you might get some of them shorting to the heat sink otherwise ...


Regards, Claas

Just checked the board on my table. Zd1 was probably touching the heat sink. The stuff around the blown cap wasn't...
 

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And wow, somewhere between carrying the amps from the table to the system one broke. Good speaker started motorboating as soon as I powered it up. Crappy speaker followed suit upon retry.

Will pull the board, trim all legs, and then go through the full setup again. Feels like I must have unreliable connections, but I made sure that solder flowed through every hole.

Didn't add new solder to all of the input, output, V-, V+, & SIT connections though, maybe that's my problem. Hopefully I didn't ruin anything. I'm going to start running out of parts even with a full spare.

Time to give up for now. Maybe tomorrow, maybe next week.
 
Fortunately I still have the F4 boards in the other half of each amp chassis, so I just unplugged V+/V- for the SS, plugged in V+/V- for the F4 and am listening to sad bluegrass. Not crappy gear at all.

So frustrating, because I did take my time today. 3 full hours of cooking at 180mV with the V- resistor in. Something about my technique is just making things unreliable.
 
be brave and chill

power on your crappiest gear and put your most beloved music and enjoy ....

once you're calm and not too eager while building something , simply enjoying process, it'll result in better job done

When I pulled the board to trim, it looks like maybe my output wire was too far through the board and may have been shorting on my heatsink.

Reinforced all boards connections, reset all trimpots, pulled the jumper, and am restarting setup. Looks promising.
 
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Damn, got all the way to adjusting r7 and it looks like I broke the trimpot when resetting. Moving doesn't effect mv reading and I never hear a "click" from hitting one end of the resistor setting. Guess I have to pull the board again, replace the pot, and redo the entire process... So close.

Your "sticktoitiveness" is to be admired and will be rewarded.

You helped get mine up and running. I can't thank you enough. At the risk of potentially pointing out the obvious.... check both jumper pins. I know someone that spent 30 minutes of frustration with a meter probe on the wrong JP pin... I won't name names though.... ;)

Edited to add - Oh - FWIW not all of my pots make a "click".
 
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