Hello all
I know i post about this one a few weeks ago, But i'm really stuck on this and the original Post i made has sadly little help,
I'm completely lost on this one
This amp came in with a blown fuse, Replaced fuse and with lamp limiter on can see excessive current draw
On removing covers i found that one channel was down, with that disconnected i can test the amp so i know one channel is good and one blown
I found one of the bridge rec s/c , Replaced that still drawing excessive current
Could see that R233 and R226 showing signs of getting hot , compared to the others
Tested ok so i decided to block change all transistors and drivers as i had them all
All transistors tested ok, but i need to be sure
Tested still the same, I found tryristor on the output socket board to be S/C
Replaced that still the same, with the Tryristor removed i can power the channel up
At this point i put the unit down for a few days
On re testing this is what i have
voltages on faulty channel are as follows all checked while on lamp limiter
-35V on the output speaker socket
peavey_xr8600_sch.pdf
Q201 - B+97v C +35v E+97v
Q202 - B+97v C +35v E+97v
Q210 B +35v C+35v E+35v
Q207 B +35v C+35v E+35v
Q216 B +35V C-35v E +35v
Q214 B +35V C-35v E +35v
Q219 B - 97v C -35v E -97v
Q220 B - 97v C -35v E -97v
Q200 B +27 C +97v E +35v
Q208 +35 all pins
Q221 B - 35v C-97v E -35v
Q215 B -35v all pins
R 252 but has got burnt,, still ok ,but replaced it anyway
15+ /15- present and 25V +/-
as stated before all the output transistors and 4 drivers ( all of the above ) been changed for new and like for like
all have been checked that they are ok and correct and in the right positions
I would really appreciate any help on this one
Many thanks in adavnce
MR A
I know i post about this one a few weeks ago, But i'm really stuck on this and the original Post i made has sadly little help,
I'm completely lost on this one
This amp came in with a blown fuse, Replaced fuse and with lamp limiter on can see excessive current draw
On removing covers i found that one channel was down, with that disconnected i can test the amp so i know one channel is good and one blown
I found one of the bridge rec s/c , Replaced that still drawing excessive current
Could see that R233 and R226 showing signs of getting hot , compared to the others
Tested ok so i decided to block change all transistors and drivers as i had them all
All transistors tested ok, but i need to be sure
Tested still the same, I found tryristor on the output socket board to be S/C
Replaced that still the same, with the Tryristor removed i can power the channel up
At this point i put the unit down for a few days
On re testing this is what i have
voltages on faulty channel are as follows all checked while on lamp limiter
-35V on the output speaker socket
peavey_xr8600_sch.pdf
Q201 - B+97v C +35v E+97v
Q202 - B+97v C +35v E+97v
Q210 B +35v C+35v E+35v
Q207 B +35v C+35v E+35v
Q216 B +35V C-35v E +35v
Q214 B +35V C-35v E +35v
Q219 B - 97v C -35v E -97v
Q220 B - 97v C -35v E -97v
Q200 B +27 C +97v E +35v
Q208 +35 all pins
Q221 B - 35v C-97v E -35v
Q215 B -35v all pins
R 252 but has got burnt,, still ok ,but replaced it anyway
15+ /15- present and 25V +/-
as stated before all the output transistors and 4 drivers ( all of the above ) been changed for new and like for like
all have been checked that they are ok and correct and in the right positions
I would really appreciate any help on this one
Many thanks in adavnce
MR A
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