Ashdown Peacemaker 20 , 2003
 

Loss of valve preamp due to o/c dropper between HT1 and HT2.
Not the slightest sign of any heating to this 1/3W , 10K resistor . Never
seems right to me 1/3W resistors in valve anode supplies - the 4 ,per
anode, 1/3W 100K and 220K droppers downstream of the HT2 supply also look
perfect . Same body colour as all the other 1/3W and no schematic indication
of being a thermal fuse resistor. So replace with higher wattage or not.?
Replace with a higher wattage and a current fuse, somehow, in case an
overload could have knocked out this R without leaving the slightest trace
of heating on it or the , more likely, higher resistance ones. I intend
milling holes inter-trace, again (previous owner of a Peacemaker 60 grateful
for the cooler running), through the pcb around the o/p bottles. Like all
these Peacemakers, serious overheating of the pcb material etc, and this
dropper is an inch from an output valve. No actual pcb discolour under this
dropper , that stops about 1/2 inch from the bottles so I have difficulty in
assuming its a heating problem. Or milling vent holes and only 1/3w 10R,
metal oxide resistor replacement?


--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/

Ashdown Peacemaker 20 , 2003
 

N_Cook wrote in message
...
Loss of valve preamp due to o/c dropper between HT1 and HT2.
Not the slightest sign of any heating to this 1/3W , 10K resistor . Never
seems right to me 1/3W resistors in valve anode supplies - the 4 ,per
anode, 1/3W 100K and 220K droppers downstream of the HT2 supply also look
perfect . Same body colour as all the other 1/3W and no schematic
indication
of being a thermal fuse resistor. So replace with higher wattage or not.?
Replace with a higher wattage and a current fuse, somehow, in case an
overload could have knocked out this R without leaving the slightest trace
of heating on it or the , more likely, higher resistance ones. I intend
milling holes inter-trace, again (previous owner of a Peacemaker 60
grateful
for the cooler running), through the pcb around the o/p bottles. Like all
these Peacemakers, serious overheating of the pcb material etc, and this
dropper is an inch from an output valve. No actual pcb discolour under
this
dropper , that stops about 1/2 inch from the bottles so I have difficulty
in
assuming its a heating problem. Or milling vent holes and only 1/3w 10R,
metal oxide resistor replacement?


--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/



very odd, scraped along the 10K, now removed, and 2 breaks one at an end
then another about 300R from the other end with no sign of discolouration on
the oxide layer, or cracks