Boogie MKIII - reverb missing, need help restoring

[Rolf Sartin]

Hello Everyone

My Boogie MKIII has never had reverb fitted from new - there are component omissions on the PCB. I've bought all the original Boogie critical parts - Tank, Xfmr, valve & base, cables, pot & knob - but I've now ground to a halt as the schematic that Mesa sent me is practically illegible (Mesa concede this point but insist that it's the best copy they have).

I can't read the component values with sufficient certainty to go ahead so I'm requesting that a kindly soul, owning a 'verbed Boogie MKIII (or indeed a legible schematic!) can help me identify the mystery passives.

I attach the schem scrap and a photo of the area around V3 (and draw attention to R241, R242, R116, which appear as vacant positions on the PCB but are npowhere to be seen on the schem!) in the hope that this may be clarified, else I'm stuck with a box of pricey original parts!

Many Thanks in advance

[52 Bill]

If there is no one with access to another amp, try checking the schematics for other model Boogies. The reverb circuits will all probably have similar values, and you may find a much clearer schematic.

I've done this before in trying to find resistor values for their foot switching circuits.

[danmagruder]

Mesa Boogie MKIII rev schematics

I have attached a word doc that has a scan of the schematics with the reverb section. Good Luck