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Need schematic for SWR LA 15 combo amp.
- Thread starter pbdog
- Start date
from the SWR website....
A: To request a schematic, please provide your full name and mailing address (or fax number), along with the model and serial number of your amplifier. Send your request to [email protected], or contact the FMIC Consumer Relations Department, 480-596-7195.
A: To request a schematic, please provide your full name and mailing address (or fax number), along with the model and serial number of your amplifier. Send your request to [email protected], or contact the FMIC Consumer Relations Department, 480-596-7195.
I have acquired one of these with "blown transistors."
Let me just say, they are not built very intelligently inside, at least mine wasn't. The output transistors are mounted on a small finned heatsink, and this is mounted to the rear plate. There are no ventilation holes. Problem is, the cooling fins are not oriented vertically where convection would help cool it -- it's mounted sideways! So this is why these overheat. Poor design considerations. The LA series were also made in Indonesia, if anyone was curious.
This website has an "A" revision of the schematic. I must have a "B" revision board due to the soft-start components. I've got to fix this thing in the next few days. Has the output transistors changed any in revisions? 2SC2837's, driven by a C4382 and A1668, with a C3834 bias?
SWR la12, la15 Service Manual free download,schematics,datasheets,eeprom bins,pcb,repair info for test equipment and electronics
Let me just say, they are not built very intelligently inside, at least mine wasn't. The output transistors are mounted on a small finned heatsink, and this is mounted to the rear plate. There are no ventilation holes. Problem is, the cooling fins are not oriented vertically where convection would help cool it -- it's mounted sideways! So this is why these overheat. Poor design considerations. The LA series were also made in Indonesia, if anyone was curious.
This website has an "A" revision of the schematic. I must have a "B" revision board due to the soft-start components. I've got to fix this thing in the next few days. Has the output transistors changed any in revisions? 2SC2837's, driven by a C4382 and A1668, with a C3834 bias?
SWR la12, la15 Service Manual free download,schematics,datasheets,eeprom bins,pcb,repair info for test equipment and electronics
I just got one of these for $100.00 !! It is like new in the original packing and was returned as defective but I cant find a thing wrong with it. Maybe after 2 or 3 hrs. it will overheat and shut off? I would like to add a fan to it if it would help. Any ideas where I can mount a fan??
It sounds good on the floor backed up to a wall. Thanks!
It sounds good on the floor backed up to a wall. Thanks!
