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rp
July 25th 03, 03:24 AM
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Hello,
I need to put a screen resistor on an EL84 based guitar amp. I'd like to
use one the unused pins - 1, 6, or 8 - as a support terminal to
attach one side of the resistor to: e.g. resistor across 1 & 9 with the
B+ connected at 1. On a 6L6 I would use pin 6 as a support since it
is labeled NC - not connected. Looking up the basing for the EL84 shows
the 1,6 and 8 pins as IC - internally connected. I believe this
is what NC and IC stand for but I could be wrong. So I'm not sure what
would happen if I put the B+ on the 'blank' pins on the EL84.
Is IC the same as NC? Can I do it?

TIA -rp

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Browntimdc
July 25th 03, 03:59 PM
rp > wrote in news:3F2094CA.84C16097
@usadatnet.net:

> ***NOTE*** Please remove -nospam- from address when replying ***NOTE***
>
> Hello,
> I need to put a screen resistor on an EL84 based guitar amp. I'd like
to
> use one the unused pins - 1, 6, or 8 - as a support terminal to
> attach one side of the resistor to: e.g. resistor across 1 & 9 with the
> B+ connected at 1. On a 6L6 I would use pin 6 as a support since it
> is labeled NC - not connected. Looking up the basing for the EL84 shows
> the 1,6 and 8 pins as IC - internally connected. I believe this
> is what NC and IC stand for but I could be wrong. So I'm not sure what
> would happen if I put the B+ on the 'blank' pins on the EL84.
> Is IC the same as NC? Can I do it?
>
> TIA -rp

IC means internal connection, that pin may or may not be connected to an
element in the tube, depending on the manufacturer. The grids and the
plate are typically anchored to two pins but often only one pin is called
out for the connection. On miniature glass base tubes you can just look
in and see what's going on. With octal you can't see. What you can do is
use an ohmmeter or continuity checker and measure between pin 6 and each
of the others and you'll see what else it's connected to.

Tim