J

You need to use powdered iron cores, not ferrite, for the LPF.

The T-200-2 cores are readily available from California at around $5.00 each
Cnd:

http://www.cwsbytemark.com/prices/coresrf.php

Even though your large air core coils are at right angles, they are still
fairly close together and there will still be a fair amount of mutual
coupling between them. The field from a 90mm dia air core coil is
unbelievably large as I found out in my DX crystal radio-building
experiments...so who knows what effect this is having on the LPF.

Steve / VE7SL

Web: "THE VE7SL RADIO NOTEBOOK" at   http://www.imagenisp.ca/jsm

PS...what configuration is your daytime beacon running??...it looks like a
CW ident or two, followed by a few long dashes?