[Boatanchors] BC-9 Loop Test: Scratching My Head.

[David Stinson]

Well, I set the BC-9 up on the front porch with
the loop.  Not enough room on the barn bench.
https://goo.gl/photos/JUyd5kSeLdZkKK5p9

The loop is very close to the original's size-
about 12 feet around.  It tunes 4.2-4.4 MC,
roughly the designed spread.   I put on the
extensions and that brought it down into the
75 mtr band.  

Using the Hi-Q loop meant the higher gain
of the triode-connected 6AQ5 is no longer
needed and an 01A in the RF stage now 
oscillates just as it should.  The lower gain
should reduce the "Miller Effect" and reduce
the frequency shifting between TX and RX.

But here's the head scratcher-  It didn't.
Big copper loop or external tank coil with
link coupling to an antenna or length of RG8,
they all exhibit transmit freq. dropping 12-14 KC
from the receiver freq.  Higher-Q loop with lower
gain tube made no difference at all.

I just don't get it.  This rig is now operating
as designed.  This model was built from 1921 to 
1931 at least.  It was in service all that time.  Yet
I cannot see how these could have been "netted."
Stumped....

73 DE Dave AB5S