I picked up this old sweep marker/generator a while back, and thought it would make a good enclosure for some multi-test equipment. I plan on building a pair each of capacitor sub boxes (one pair is going to be Mallory 150 series, the other OD PS series) plus heavy duty potentiometers to dial in dropping string resistors, bias range resistor, preamp cathode resistor, and a selector switch setup for cathode bypass caps. Also i have space inside the enclosure to house Martin Mannings wonderful 300W dummy load setup (Thanks Martin, its my go to tool every day!) Everything would connect to the circuit via banana plug cables.
My biggest concern is swapping out bypass caps and signal caps while the amp is live. The switches i am looking at getting are 120VAC 5A 50vDC rated - i think this would be ok as the B+ side of most signal caps see roughly what, no more than 3/4 amp current draw? I know you can use a bleeding resistor across the capacitor to prevent the inevitable loud popping noise you would get if you switched capacitors - and ive also read that each capacitance needs a different amount of resistance to prevent the popping noise. How would you figure this out (even if i have to resort to...ugh...math
) without spending a lot of time swapping out resistors?I also made a faceplate for it, so it doesnt look like i butchered a perfectly good looking, albeit useless piece of test equipment
