Bought a Peavey CS800 power amplifier and upon pickup this guy that looked like he was ready to kneel over and die had set it in a pile of melted snow in his driveway. It made a mess of my car but when I got it home I took it apart and let it dry for two day. Cleaned it up.
tested the power switch and it works fine. Tested the power transformer and it reads a 0.3 - 0.5 ohms upon leaving the secondary side and entering the fuses on the power board on both leads. Does this mean the power transformer is good as well as the switch?
tested the power switch and it works fine. Tested the power transformer and it reads a 0.3 - 0.5 ohms upon leaving the secondary side and entering the fuses on the power board on both leads. Does this mean the power transformer is good as well as the switch?
I wouldn't worry about a little snow melt water. We used to steam clean PCB's at GE appliance factory to get the oily junk off. Salt water now, can cause things to rust.
Power transformers hardly ever burn on these things.
There are about 8 revisions; a picture might help pick a schematic. Lots of them had a triac in the bottom to power the actual transformer, the power switch only turned the triac gate on or off. Rev C used up to 9/82 had a TO220 triac on a little board. Later ones had one that mounted to the case bottom as a heat sink.
If yours is 7" high and has a big grill in the front panel, you're in luck, its an X. Great sound out of those.
The ones with a solid front panel, the A's & B's had a 741 op amp which hisses some in low wattage hifi service. Still good for 300 w/ch rock & roll with no soft songs, though.
With your DVM do a double diode test on some output transistors. Also look that some output transistor emitter resistors are really 5 ohm (two 10's parallel usually). Those are usually blown by the 1/4 phone plug to the speaker being pulled part way out on stage in the dark. Pros in the 80's used dual banana plugs for speakers that wouldn't short pulled out.
You'll find most of the threads on these things under "PA systems" forum, since they are a PA amp, not a guitar amp. More highs than a guitar ever needs. No intentional distortion, either, which guitar amps have in abundance.
To upload pictures from your PC press "go advanced" buttom at bottom of posts and follow instructions. You'll "browse" your hard drive for the file, then press upload to get it to show on the main panel.
Power transformers hardly ever burn on these things.
There are about 8 revisions; a picture might help pick a schematic. Lots of them had a triac in the bottom to power the actual transformer, the power switch only turned the triac gate on or off. Rev C used up to 9/82 had a TO220 triac on a little board. Later ones had one that mounted to the case bottom as a heat sink.
If yours is 7" high and has a big grill in the front panel, you're in luck, its an X. Great sound out of those.
The ones with a solid front panel, the A's & B's had a 741 op amp which hisses some in low wattage hifi service. Still good for 300 w/ch rock & roll with no soft songs, though.
With your DVM do a double diode test on some output transistors. Also look that some output transistor emitter resistors are really 5 ohm (two 10's parallel usually). Those are usually blown by the 1/4 phone plug to the speaker being pulled part way out on stage in the dark. Pros in the 80's used dual banana plugs for speakers that wouldn't short pulled out.
You'll find most of the threads on these things under "PA systems" forum, since they are a PA amp, not a guitar amp. More highs than a guitar ever needs. No intentional distortion, either, which guitar amps have in abundance.
To upload pictures from your PC press "go advanced" buttom at bottom of posts and follow instructions. You'll "browse" your hard drive for the file, then press upload to get it to show on the main panel.
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