Fwd: Hopefully on topic

Martin Crockett crockett.martin at gmail.com
Mon May 4 22:10:16 CDT 2020

Hi all,

I now have just acquired a VT-100 and am in the process of checking it out.

I noticed there is a capacitor that has vaporized, but I cant determine
what value it is.

I have the DEC VT-100 maintenance guide but it is very blurry in the
relevant area.

I cant even read the board designation.

This is the area of the circuit, I can trace the 2 Zener diodes on the -23V
rail, to one end of the cap, the other end seems to go to ground. The
obvious culprit is C6, but that doesn't match the mud map of the board, as
in C1x.

This is the capacitor in question.

It looks like C1x where x is undetermined.

I think it was a ceramic monolithic capacitor, it seems to be different to
any other caps on the board, i.e. slightly larger and a different colour
blue. When I look at this hires photos on Google images, it is the blue
capacitor circled below

Does anyone have a VT-100 and mind checking what the value of this
capacitor is please?
Ideally value and voltage or even just the nomenclature written on it, I
can work out the value and voltage from that.

Many thanks and Cheers, Martin...

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