[Milsurplus] BC-223- On The Air

[David Stinson]

I epoxied the "J" extension, which I had infused with the 
green "Locktite" product, back onto the casting and 
glued a brace for it made of a bit of circuit board to 
the housing on the right.  
It appears to be back in service- so far, so good.

http://home.netcom.com/~arc5/BC-223/BC223.jpg

The "shiny" is finishing oil- I haven't wiped-off 
the excess yet.  

I made my first CW contacts with the set last night
using a bug.  20 WPM keying was no problem.
Like all MOPA sets, it does have a little "chirp," 
but not bad if tuned correctly.  Turn the "ANT IND."
control just slightly clockwise from max output.
I agree that there isn't enough drive when using
crystals- the "correct" large-blank ones,
not to mention little 243s.
I'm going to build a "clock oscillator" board
to sub for crystals as I've done successfully
with other sets.

I haven't tried to get the set working on AM 
because half of my  PE 125 AX vibrator supply 
has bad iron.  It seems to work fine on CW
with just one side working.
I'll let AM wait for another day.

The MO and PA tubes in the BC-223,
801s, suffer from "Audiophoolus Grabbus" disease.  
They are terribly expensive.    However, like the 
BC-230 and unlike the MO in the BC-375, 
it seems inexpensive substitutes can work.
I plugged-in the two 6AQ5 adaptors I'd made
for the BC-230 and it worked fine with full 
output, just like 801s.

http://home.netcom.com/~arc5/BC-223/subbedtubes.jpg

NOTE:  This is a savage over-revving of 6AQ5s.
I only installed them as "proof of concept."
They never showed color during a few cycles of 
"quick brown fox" on CW, but you can bet they
were sweating.
Attempting to use them with a heavy duty-cycle
like AM phone will certainly destroy them.
In the future, I'll look for a cheap tube that 
can be safely subbed.
I didn't try to sub the audio tubes because 
46s are not "Audiophoolus Grabbus" infected
and are still fairly common.

Time to clear the decks for the next project.

GL OM ES 73 DE Dave AB5S