Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems.

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #1   Report Post  
Posted to sci.electronics.repair
external usenet poster
 
Posts: 5,247
Default 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/


  #2   Report Post  
Posted to sci.electronics.repair
external usenet poster
 
Posts: 5,247
Default 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


Reply
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules

Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Ashdown Peacemaker P60 valve combo, 2003 N_Cook Electronics Repair 9 October 21st 08 08:32 AM
Ashdown MAG 300 N Cook Electronics Repair 5 August 16th 08 02:53 PM
Ashdown ABM EVO-II 500, 2002, bass amp head N Cook Electronics Repair 10 February 12th 08 03:51 PM
Ashdown ABM500 bass amp N Cook Electronics Repair 9 September 26th 07 11:25 AM
Ashdown Mag 200 bass amp n cook Electronics Repair 14 May 17th 07 04:21 PM


All times are GMT +1. The time now is 02:03 AM.

Powered by vBulletin® Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 DIYbanter.
The comments are property of their posters.
 

About Us

"It's about DIY & home improvement"