Hello LowFers,

I appologize to all who called me in vain this weekend. These days I am
thinking of a preselector based on the following idea. I will mix the
input signal 136 kHz in  a   v e r y    t o u g h   mixer to frequency 9
MHz, then I let the signal go through a crystal filter (SSB or CW, maybe
switchable), then I will mix back to 136 kHz with the same oscillator.
The oscillator will be tunable. This should work as a very selectable
"preselector", which would be capable to filter out even very close
DCF39. Any ideas?

I updated my WEB pages, mainly photos added. You can start at the very
home page
http://www.mujweb.cz/www/ok1fig/index.htm
or you can go to main page for LF
http://www.mujweb.cz/www/ok1fig/136k.htm
or you can visit Picture gallery
http://www.mujweb.cz/www/ok1fig/gallery.htm

73! Petr, OK1FIG