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Gareth Magennis Gareth Magennis is offline
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Default Peavey Valve King 212



"N_Cook" wrote in message
...
Gareth Magennis wrote in message
...


"N_Cook" wrote in message
...
only 6 months old , barged into a door apparently but owner cagey. No
mention of what happened when powered up. 10 watt resistor overheated
to
burn up cabling and black "candy floss" everwhere inside.
Will be a while before I can get any power onto it, schema on
elektrotanya.
But anyone know the DC ohmages of the transformers ? These readings
look
ok
, genericaly speaking
o/p primary 29.8/24.6 R

mains primary for 240V 4.4R
sec
heater 0.4R
HT 14.2R
other DC 74.4R





Saw one of these a while ago and had to hard wire the ribbon cable
between
pre-amp/power amp boards as it had arced/burnt the connectors.

One thing I particularly remember is the OPT input feed is connected via
a
plug and socket to the output PCB and, unlike most Peavey units, it is
possible to connect this the wrong way round. This will result in all

sorts
of weird feedback/oscillations, particularly when playing with the
"resonance" pot on the back panel.

This amp cost me a lot of time and frustration.



Gareth.





At least the OPT wires are proper 500V rating. I ' ve now marked that
connector JIC.
I imagine your ribbon problem was initially the euro-crap solder inside.
I've pared off the HT wire and spiral wrapped some sleeving around it. The
wiring to the standby switch will go the other side of the main caps not
over the replaced 400R 10W dropper that had exploded to 3 bits in the
conflagration.




I think it was actually the heater circuit that burnt the connector
contacts, though I'm not 100% sure of that.
I've seen this same burning on other equipment too, usually the high current
PSU connectors, (Molex?).


Gareth.