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gareth magennis gareth magennis is offline
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Default Phonic 1062 mixer amp,2006



"N_Cook" wrote in message ...

1 channel only
Elektrotanya SM is for the linear ps version and also lacks the power
amp schema in full etc, no other schema found.
I've not tried powering up since on receipt , removed from the cab.
Exploring cold first. As ps rails are paralleled for the PAs, the ps
must be ok.
What are the 2 black epoxied lumps labelled POD1062X that look like
epoxied torroidal chokes. But according to the (wrong) 1062 version
schema they are an IRFP250, presumably 3 pins, 1 pin obscured.
Rail switching between 40V and 70V rails + & - on power demand.
Anyway cold testing , seemingly as inductors , one is s/c and the other
o/c which explains why a toroid with 2mm diameter wire wrapped around it
can be o/c with no hot spot,at least, to be seen. So if mainly a
powerFET, what else , not suggested on the schema, would be under the epoxy?
in this pic with red Xs
http://www.diverse.4mg.com/phonic1062.jpg
all o/p devices test cold DVM-D ok, so a shorted rail switcher makes
sense and goes into protect mode on one channel but there is 2 of these
POD1062X per channel and only 2 here, unless 2 in one pack, explains the
difference in overlays , other than the POD number , also different
datecodes on each, but would require 6 pins each then, 4 hidden.
Will power up on the bench and then remove all those screws to explore
the hidden side of the board





IIRC, In the Studiomaster, X and Y were just 2 toroid chokes, but not
covered in epoxy.

No hidden transistors there.



Gareth.