[Milsurplus] BC-9: Working With That Choke.

[David Stinson]

Had some fun this morning with the BC-9 and its
big copper-tubing loop on my kitchen table.
Had a nice QSO with Ronnie, W5SUM for 
Novice Rig Roundup on 3555 KC.  
About 180 miles.  Not bad for a "trench radio"
designed to talk 3 miles. The loop is directional. 
At least I can null line noise, LOL.

I started tinkering with the new RFC in 
the plate shunt feed.  I put a 470 pFd SM 
in for C6 and, surprise, I'm all the way down 
to one of those Radio Shack 100 uH ferrite 
chokes with very little change in offset-
still about 200 Hz.   To mean, this confirms
that the Filter in the Plate and Grid circuits
was carefully designed specifcally for the 
VT-1.  Somewhere under 100uH things
should start moving. I expect that, once 
we're 'in the ball park," there will be significant
differences between tubes.  We'll see.

I'm thinking of ordering half a dozen of the 
Molded fixed inductors from Digikey
and seeing if I can hit on "good."
What do you think?

I will have the BC-9 on the external Delta
loop tonight crusing around 3550 for 
Novice Rig Roundup.  See if I can 
work the world on that might 2 watts.

We're close to calling this project "done,"
I think.  Still have to put the power supply
in a proper box.
Going to print-out all our discussions and
see if I can edit them for an ER article.

73 DE Dave AB5S