On Sat, Nov 20, 2021 at 08:14 AM, John Hudak wrote:
if there is a way to test them out of the board
AFAIK, the TD was used in the pulse generator sub-system of the triggering system... of 'older' Tek scopes. (500? 400?) ... I think, 453,454 used a TD that way.
AFAIR TD is used as a fast (relative to the day) current controlled switch, with a bias current (453,454? et. al?)
Anyway, IMO you'd have to test the TD that way, it that's how it's being used in the trigger system... I'm speculating. (You don't say which Tek scope you're working on.)
IMO (and since you profess proficiency with pcbs) ... I'd be more worried about damaging the tunnel diode 'testing' it.
Since you're probably (most probably) only going to find the right TD, for your scope (whichever Tek it is) in another similar Tek scope with a working trigger... if it the diode is blown
--
Roy Thistle
