I would go directly from 45MHz to 455kHz..............this is typical in HF
receivers. An NE602 mixer can be used for the 2nd mixer and a 44.545MHz
crystal used with the on-board oscillator allows you to derive your 2nd I.F.
Alternatively, you can use a TDA1572 as the 2nd mixer/I.F./ demodulator.
This is also a good system and it will give you fairly good strong signal
handling capability.

Pete

"Netgeek" wrote in message
...
Parts are on the way...

First IF = 45 MHz
Second IF = 10.7 MHz

Any point in going further to 455 KHz for a third IF or just stick
with the 10.7 - (MC1350 plus IF transformer) scheme?

Bill

"RST Engineering" wrote in message
...
I'd probably jack the IF up to 45 MHz. (use TV parts; this is the TV IF
frequency) or 70 MHz. (satellite IF frequency), and then downconvert to
either 21.4 or 10.7...there are cheap crystal filters at both
frequencies.

Jim


In the meantime, any other suggested improvements or hints are
most appreciated (e.g. "up the IF from 10.7"?)...!