Re: 577 AC collector supply not reading zero on display

DW
 

I should note the feedback here has been noted and considered so far here.

I have avoided shaping the brush to a sharp point as I was observing how the other variac had a point but it was blunt on the end so I worked to mimic that, somewhat by slightly giving a flat roll off on on just the two ends.

Vertical lines represent contact area to windings.
---||||----------- <Winding
| |
|_ _ | < Brush

| |
| | <Top view of contact area of brush
| | winding aligns perpendicular to this


These adjustments I am making are only brief and temporary, I am just experimenting to see how I can get the collector supply to 0 volts.

Obviously as noted I want to make absolutely sure the carbon brush is making a wide enough contact patch to prolong the life of the variac for the long term.

Also the brush was running off the winding on to a metalic platform. I observed the control slightly sticks as the brush has to overcome the lip of the first winding, as Chuck noted and as I obviously noticed, I don't want this to occur to avoid premature failure. I will readjust approximately.

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