Smokin Aleph2

[pythagoras]

Im in the process of building a pair of aleph2's... When I power up I get +43VDC across the output. After 3-4 mins R16 (220k) eventually gets so hot it breaks down and smokes.

The same thing still happens if the I disconnect the output boards from the main board so I guess the problem is with the main board? Any pointers as where to start faultfinding would be good. Otherwise I guess Ill recheck all the components again :-(

 

[Netlist]

Welcome to the forum pythagoras,
I'll keep my congrats till your Aleph2 is fixed.

Aleph2 you say?
R16 220k?
Are we talking about the base resistor of Q4?
Not that it matters for the smoke, but it should be 150 ohm

Please explain and give some more details.

/Hugo

 

[pythagoras]

...Thanks Netlist, your right R15 was the resistor I meant not R16.

Found the problem...
Q2 was dead (shorted)??. Changed that now everything works fine I'll post some pics of monoblock in the next few days. Thanks

 

[promitheus]

congradulations on solving your problem.
Waiting to see your finished amp.

 

[Netlist]

[B
Found the problem...
[/B]

Well congrats then; still R15 is also not 220k but 220ohm.
But that's probably what you meant?

/Hugo