[Milsurplus] BC-9: NETTED! WoooHOOO!

[COURYHOUSE at aol.com]

Congrats Dave!
Perseverance paid off! 
 
I learned   things  during this  dialog   too!
 
Write up a  final  report and photos  end  etc   and I  will post on SMECC  
I am sure 
if anyone is lucky to get one of these  gems  your experience  will save 
them a lot of agony!
 
Ed# _www.smecc.org_ (http://www.smecc.org)  
 
 
In a message dated 2/19/2017 4:58:16 P.M. US Mountain Standard Time,  
arc5 at ix.netcom.com writes:

You  know, I am grateful to The Almighty for 
getting me in touch with such a  grand community
of  sharp people who are generous of  spirit.

The BC-9 is Netted!  WooHoo!
The solution was indeed to  insert a *real*
RF Choke in the DC shunt feed to the Osc.
Plate.   C6 is no longer needed (nor has
any effect) and the external RF chokes  
on the 120VDC line are eliminated.  
Here's the revised  diagram:
https://goo.gl/photos/y6mJsdF9RrYDZzJN9
All you folks working  on replicas, take note.

I'm still impressed with how stable this  rig
is and how little chirp.  Of course, the DC/DC
converters  provide excellent voltage regulation
at such low load levels.

The  receiver and transmitter net to within
just a couple of  hundred  cycles from one
end of the band to the other.  And this 
is  consistant across tube types.
I tested 01A, Triode-connnected 6AQ5
and  VT-25A.  All behaved similarlly.
Note that, with the loop, the 6AQ5  is
not the best tube.  It does something 
at high bias levels that  causes the audio
amps to motor-boat.  Don't know what.
The VT-25A  is the best for both TX and RX.
And that's with only 6.5 V on the  filament
of a 7.5V tube.  Tight fit but it goes.
Figures; Can't get  a $600 tube, so
the best one is just $125, LOL.

I will be tinkering  with the rig on the big
copper loop tonight around 3555 KC +/-.
If you  hear a little signal with a little
wobble, let me know, HI.
Discovered  that the radio might even work
on 40 meters.  Already pushed it to 6  MC
and it worked.  Another time.

Gentleman, I lift my soldering  iron and
doff my hat to every one of you who 
contributed thoughts and  suggestions.
You are the very best.

GL OM ES 73 DE Dave  AB5S


______________________________________________________________
Milsurplus  mailing list
Home:  http://mailman.qth.net/mailman/listinfo/milsurplus
Help:  http://mailman.qth.net/mmfaq.htm
Post:  mailto:Milsurplus at mailman.qth.net

This list hosted by:  http://www.qsl.net
Please help support this email list:  http://www.qsl.net/donate.html

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20170219/aea7ec89/attachment.html>