[AMRadio] DX-100B, output falls off gradually

[Rick Poole]

At 12:42 PM 11/20/2011, Gary Schafer wrote:

 >>>>>
>The fact that you say pin 1 of the rear jack is at ground no matter where
>the mode switch is would point to:
>Someone placing an internal jumper across pin 1 to ground.
<<<<<

It appears that is what happened... more specifically, someone 
apparently placed a jumper across the Plate switch so that the VFO 
and buffer cathodes are always grounded.

Turns out this is part of the rework of the DX-100B so that it will 
work with the SB-10, at least according to one of the illustrations 
in the SB-10 manual.  I haven't figured out why, yet.  But 
regardless, I'm not going to be using the SB-10 anyway, at least not 
any time soon, so I'm going to remove that jumper and maybe 
substitute an internal switch until I figure out why the jumper is 
there to begin with.

It's going to be a couple of days before I can wrestle that big block 
of iron over to the workbench... having an arthritis attack so it's 
all I can do just to walk... and anyway I just blew up one of the 
modulator tubes (it developed an internal short) so I need to wait 
for a replacement to show up at my door before I can take this little 
project any further.

Rick WA1RKT