PDA

View Full Version : Mesa Switching


drewl
12-29-2007, 03:36 AM
UUGGHH!!
I hate these things....they never match the schems...some have relays, others LDR's and the stupid FETS are nowhere on the prints.
Got a Dual recto solo head that had no cln channel 1, and no sound in any of the loop modes so no loop master volume or solo pot either.
Channel 1 problem was solved by replacing a bad FET and I can get the loop modes to work by removing another FET....I'll try replacing that later....it's time for a stiff drink!

Chuck H
12-29-2007, 05:40 AM
I'm fortunate in that I don't repair amps for a living. I'm unfortunate in that I am a painting contractor. So all I can say is that when I get a job where I have to strip wallpaper and repair the sheetrock before it can even be painted, the price reflects it. There's a price for every job and it's what the market will bear.

Since I own and do my own mods and repairs to a Mesa engineered product I can certainly relate. I've worked on other amps that were just as bad...But none any worse.

Chuck

drewl
12-30-2007, 06:10 PM
Well at least they have a truth table that descibes what switching takes place in the different modes of operation.
I'll have to see what relays are actually firing and which ones are not so I can track down the culprit, whether it's a bad relay or FET.

At least if you tell Mesa what works and what doesn't they've told me where to look in the past.....I'm sure they have to go through this all the time!

bob p
12-31-2007, 11:55 PM
UUGGHH!!
I hate these things....they never match the schems...
its not that the schems are bad. you just don't have the right schems for your amp.

call mesa tech support and give them your serial number. they'll get you the right schems for your amp.