Greg Mayman wrote in a message to George White:



 GM> Theree is a lot of stuff on the 'net, but only very rarely do you
 GM> find data for outdated devices. I suspect the same would apply to
 GM> CD-ROMs :-(

 GW> But at least you can keep the _old_ CDROMS and still have the old
 GW> data.

 GM> The problem is that most of the old data never got onto CD-ROMs in
 GM> the first place.

That's one of the reasons I have a scanner,  and a cd burner.  :-)

 GW> They were normally just diodes to protect the gate against breakdown.
 GW> They clamped the gate voltage to 1 diode drop above or below the other
 GW> terminals.

 GM> Yes, they could be clamping against reversal of the control
 GM> voltage.

 GM> OTOH if they are zeners, they could also clamp the forward
 GM> voltage. Most insulated gate FETs are rated to a maximum
 GM> gate-source voltage of 15v.

I'll have to take another look and see if those parts are any better ID'd
than what I posted...

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