Tony:
http://site298.webhost4life.com/barr...ccessories.pdf
would seem to confirm your theory.

www.qsl.net/k5bcq/HK/HK.html says: (you may have to move the figures
to the correct columns)
IF Transformer Center Freq BW -6dB BW -20dB BW -40dB
BC-453 IF (#12012) 85Khz 3.0Khz 10.0Khz 26.0Khz Notes (4)(6)
BC-453 IF (#12012) 85Khz 5.4Khz 14.0Khz --- Notes(5)(6)
two BC-453 IFs (#12012) 85Khz 1.8Khz 4.3Khz 11.0Khz Note ( 8)
Notes:
4.With the Micarda rod "OUT". BC 453 IF coils have a "Q" of about 50.
5. With the Micarda rod "IN" (over coupled)
6. One of the BC-453 IF trimmer caps was modified so both trimmers are
across the fixed padder capacitors.
With both Micarda rods "OUT" (not overcoupled) ....very sharp for SSB

************************************************** ****************
Antonio Vernucci wrote:
I would assume that maximum selectivity occurs when the 85 kHz IF
trasformers actuators are fully pulled up (maximum distance between
primary and secondary windings).

Can any one please confirm or deny?

73

Tony I0JX