Dale: Wow, another Barbados RX builder. That was my first successful
superhet project. I now have the one I built (still on 20), and this
morning
I got another one (the one built by someone else on a factory-made
board)going on 17 with a VXO. I have a THIRD partially built Barbados
RX board. If this
keeps up, I'll soon have a BBRX museum.

As for the tube RX, I have a Toyo Communications CM filter. Markings
look good:
"445 -- 2.4 -- C" Now I have to figure out how to work this into the
existing
RX circuitry. Time to look through some mid-'60s handbooks and QSTs.

73 Bill M0HBR CU2JL N2CQR
http://planeta.clix.pt/n2cqr





Hi Bill,

I too built the Barbados RX- don't know what happened to it though.
Have you thought of using a Murata ceramic filter in your tube RX?
They make a 4KHz unit for under $3. Not CW selectivity, but I'll bet it will
be an improvment over what you have. Typcial Zin and Zout is around 1K.
Although I have never tried it, I wonder about the possibility of brewing
your own ceramic filter from some of Murata's 455KHz ceramic resonators.
Although not the Q of a quartz crystal, it may be worthwhile. I have some
here and think I'll put one on the network analyzer and see what
characteristics I get.

Dale W4OP