On Jul 1, 12:12 am, Eric Jacobsen wrote:
Sounds to me like the IF plan is a little screwy already, since the
200MHz IF is in the tuning band of 0.5 to 600MHz. Not sure how well
that's gonna work for ya.

Okay ... I need to pay attention to spurs from the first IF mixer when
working out a frequency plan.

For the sake of the original question let's assume that the RF range
has been changed to one which is appropriate for a 200 MHz IF.
The question still being regarding the tradeoffs of where to digitize
the signal.

Followup question being ... any good guidelines for picking the first
IF frequency other than:

1) High enough to simplify the input filters.

2) Something that is easy to build / buy a good filter for use after
the mixer.

3) Something that results in a minimum amount of spurs from the
mixer.

4) Something that isn't so high as to complicate construction more
than
necessary.

-- John