power supply modification for Eden Metro World Tour скачать в хорошем качестве

power supply modification for Eden Metro World Tour

Bob Weigel of sounddoctorin.com documents the factory modification that is undocumented as near as I can tell, in the low voltage power supply. if your unit uses tip42c 41c transistors mounted to the chassis then this is probably for you. CORRECTION AND ADDITIONAL INFO---- 4 pin i/c on left of power pcb has 18v zeners underneath to clamp potential overvoltage situations. red wires feed +15v to preamp pcbs. blue 15v but ALSO right board omits heater reg. tip32 q12 shown in diagram i have (and diodes etc. designed to bias q12) and instead loads heater with 22ohm 1W resistor soldered in place of one leg of R74. I initially assumed both rails were 100 ohm loaded in HV feed tip41c/42c complimentary power transistors. The previously burned/unreadable v one heated right up again. lol... I realized finally the 12ax7 heater was raising the drop there from 4v (16/100 watts) to 20 some volts! (over 4W on 1W res.) 4.7 ohm at .25A is under 1/3 watt..guessing they used a bit more so if someone has a readable one let us know!