So. I am definitely a novice on electronics and schematics. But a poor musicians gotta do anyway, eh?
The Peavey Bass Mark 3(300CHS) stopped producing sound and instead produced a burning smell. Let it sit for a few days and this is what I found:
By visual inspection and with the help of the schematic found here: https://peavey.com/forum/download/file.php?id=17120
...I've determined that at least CR15, R23, R15 and R39 are fried. I plan on replacing these as I know my way around a soldering iron.
However, I do not know enough to confidently measure the voltage in order to troubleshoot the circuit. Is anyone familiar with the design of this circuit? Are there any obvious things that I could look for with my multimeter/DVOM? Please forgive my lack of knowledge on the subject.
Any help is greatly appreciated. Thanks in advance!
Repair Bass Mark 3 300CHS
Re: Repair Bass Mark 3 300CHS
First, clean off the soot. I usually grab a Qtip - well a bunch of them - and isopropyl alcohol. Swab the area, and most of the soot comes off.
Any of the circuit board that is actually charred must be removed. I grind such away with my Dremel.
Of course check, but considering what is burnt, I'd say it is a good bet your output transistors and drivers are shot. SInce CR15 is parallel the outputs, if they short, it makes CR15 appear shorted. THey do fail once in a while, but very rare for that diode to fail. The drivers are the smaller transistors on the little finned heat sinks.
Any of the circuit board that is actually charred must be removed. I grind such away with my Dremel.
Of course check, but considering what is burnt, I'd say it is a good bet your output transistors and drivers are shot. SInce CR15 is parallel the outputs, if they short, it makes CR15 appear shorted. THey do fail once in a while, but very rare for that diode to fail. The drivers are the smaller transistors on the little finned heat sinks.