[R-390] RF Deck B+ short (390A)

[Dennis Wade]

Ah, ok..great info about L209.  I'll keep that in mind.

I will certainly keep all informed...but maybe not till Thurs night.

       Thanks again.  D.

On Wed, Nov 19, 2014 at 12:01 PM, Grayson Evans <wa4gvm at gmail.com> wrote:

> A little more info for you.
> My RF deck is on the bench, tubes out, everything disconnected including
> the coils
> I measure 125K from pin A to ground.  This high value is probably due to
> the coils being unplugged.
> It is very hard (for me) to trace the B+ line under all that circuitry, so
> it might be hard to disconnect someplace convenient.
>
> Notice that L209, the RF choke that is attached to pin A is 25 ohms, so
> your short is really 60-25 or 35 ohms.
>
> With the tubes removed, try measuring from the tube plate pins on the
> sockets to ground and see if you see anything weird.
>
> You got me interested, so let me/us know what you find.
>
> Grayson
>
>
> Grayson
> TA2ZGE - Ankara, Turkey
> KJ7UM
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-------------------------
Dennis L. Wade
KG6ZI
Carmichael, CA