Testing for grid current on sb-200

[Jan sluchak]

I am still unclear the safe way to test for grid current on the SB-200
that I am working on.  For those that have not read my threads, this amp
lost its grid current all of a sudden. I suspect a component went bad as
tubes are new Taylor 572b's.
So in checking, I cannot find D18 as recommened to check by a member
here.  The amp came with all Harbach mods so was D18 removed when soft
key went in?
I get 1.077 volts dc at the amp relay jack.  This was described as grid
bias also?
Please tell me the safe (realtively) place to check the grid current and
bias voltage.  At the base of the tube at the ground to grid pin?  Is
this under a load with no mic gain?
Again, the manual doesn't cover this and I would appreciate if someone
could recommend a document that does explain this.
I am also in Redwood City, below San Francisco.  As I am trying to gain
knowledge and learn through this, is there someone that can possibly
show me this testing proceedure if I go to their location.
Thanks
Jan Sluchak

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