[Boatanchors] Boatanchors Digest, Vol 100, Issue 32

[Drew P.]

Bob wrote:
 
> Hello group, I have acquired a DX 100B from a local source.
> It hasn't been run in a lot of years judging from the looks
> of it when I got it. It is probably a 7 cosmetically on a
> scale of 1-10. It is basically stock with no mods. When I
> opened it up it was obvious that a couple of caps had to be
> replaced and it had an arcing problem from the stand off of
> the two 20MFD 150 volt caps to ground. I fixed these
> problems but the most I can get out of the set is 100MA of
> plate current. I have traced that and one problem is that I
> am only getting about 86 volts DC to pin 3 of the finals. I
> should be getting closer to 185 volts. I am working on this
> although I don't know if it will be a fix or not. One other
> problem that I have noticed is that when I push the drive
> control knob in or out the grid current is all over the
> place. I can try to deoxit it but I would prefer to replace
> it. If anyone has a good orginal pot, a 25K 4 watt part no.
> in the manual is 11-20 I would like to purchase 
>  same. It is the same pot that is used in either the DX100
> or DX100B.


Hi Bob, 

Here is a link to an article on replacement of this pot with a low power pot and TV horizontal output transistor.  These parts are much easier to find and less costly these days than an original type drive pot.

http://www.amwindow.org/tech/htm/dpotd1.htm

Drew