700B blew one Right channel 5A supply fuse

Was just on my way out the door and I remembered that relay board. Shouldn't that be put in before the board goes back in place?

It looks like there's holes to drill and I fasteners I need to get.
 
Ok, let me ger dinner ate and we'll bring this puppy up. Get the DBT plugged in to the variac..
 
Plug the aamp in to the DBT and with the variac AT 0%, turn on the variac, with the amp on also....
 
Don't matter, now bring the variac up to 10%, bulb should brighten, then dim after a 10 seconds or so...
 
But if your picky, red to the rail, blak to the resistors...
 
Whats the meter say? Got fuses in? Got the bias trannies bolted back in???
 
Come slowly up to 50%, eyeballing that bulb all the time, as you move up, make sure it dims before going further...
 
laatsch55 said:
Come slowly up to 50%, eyeballing that bulb all the time, as you move up, make sure it dims before going further...
Click to expand...

At 50V on the variac, bulb just barely starts to glow but does not dim. .415 (point 415) volts on the meter.
 
Get both bias readings below 200 before we go any further, and after that check DC offset, PLEASE DON"T SHORT ANYTHING WITH THE PROBES>>>
 
The bulb should have dimmed when you lowered the bias a wee bit...
 
laatsch55 said:
Get both bias readings below 200 before we go any further, and after that check DC offset, PLEASE DON"T SHORT ANYTHING WITH THE PROBES>>>
Click to expand...

Turning down the variac to 20V made 192MV left bias on the meter. Checked bias on right side and got -10V. Offset volts .806V on Right .780V on Left
 
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