[dude_500]

Transformer, D1-D4, and .47's are all fine.

 

[amb]

Then power up and check the voltage on the negative rail MOSFETs' metal mounting tabs. If they are complements of what you get on the positive side, then check the voltages at R6 and R7 relative to G (it doesn't matter which end of the resistors you test). What do you get?

Power off and let all capacitors discharge fully, then use the DMM diode check function and check all the BJTs. I posted how to do this earlier in this thread.

 

[fishski13]

i'm placing an order with Digikey tonight and just want to make sure that C1 on the ground channel is 33pF.

 

[amb]

Quote:

Originally Posted by fishski13 /img/forum/go_quote.gif i'm placing an order with Digikey tonight and just want to make sure that C1 on the ground channel is 33pF.

Yes.

 

[fishski13]

i'm finishing up stuffing the 3rd channel. i'm going to listen to the 2-channel passive ground for one more evening before i slot the 3rd board in tomorrow. i also finished my top-plates today. i'm very happy with how the faux anodized finish turned out.

 

[DoYouRight]

great job love the mesh, as well as one not afraid to do their chassis truly hands on and not just ordered.

 

[nattonrice]

How did you affix the mesh to the panel?
I had a similar idea for the top panels back when I started but was worried that without using bolts there was going to be a problem if someone pushed the mesh into the amp.
(shorting out and such)

 

[fishski13]

Quote:

Originally Posted by nattonrice /img/forum/go_quote.gif How did you affix the mesh to the panel? I had a similar idea for the top panels back when I started but was worried that without using bolts there was going to be a problem if someone pushed the mesh into the amp. (shorting out and such)

8 strategically placed small blobs of regular JB Weld epoxy per face-plate

. i weighed the perf steel down with 4 lbs of heatsinks raised up on 1x1" pieces of scrap wood so that there wouldn't be any sagging.

 

[fishski13]

epoxy is like duct tape for chassis work, except for when it sets, it's permanent

.

btw, i scored lines on the backside of the top-plate to line the mesh holes up proper with the vent holes.

my face-plates from FPE should be here on Monday.

i'm going to rip out the Supra cable direct connection to the PEC pot and install proper RCAs with cotton sheathed solid silver - i'm a cable dork and need the flexibility of swapping cables.

anyway...the B22 continues to impress. i can't wait to hear what an active ground channel will do.

 

[IPodPJ]

http://www.head-fi.org/forums/f6/b22...elcome-450901/

 

[sachu]

That's blood brilliant!!..great going on the design.

 

[IPodPJ]

Thanks!

 

[fc911c]

very classy design, well fitting for the B22

 

[fishski13]

iPod,
very sexy.

 

[dude_500]

-45 and 45V across the FET's heatsink tabs. The negative side doesn't bleed on its own and still has -40V on them an hour later.

R6 and R7 have only 100mV on them with respect to ground which appears to be wrong. The positive side has 30V on those resistors. Should I proceed to test BJT's based on this data?