Hi all,

I'm Paolo from Italy, this is my 1st post. I'm trying to align the IF
filters of the R&S EK-07. From a general standpoint, I would like to
understand what the recommended procedure should be. I just followed
the
manual:

- a sweep at the antenna input, centered at the tuning freq. I
generate
this sweep from the combination 141T/8443A
- the 300kHz IF output and the scan ramp output of the sweep at the
scope in XY mode
- auto AGC

The filter has six fixed positions, the narrowest is 300Hz (crystal
filter) and the widest is 12kHz. The - only - tube is biased by AGC.
I
observe large modifications of the symmetries depending on the
combination sweep rate/AGC time constant: if there's enough time for
the
gain to get stable, I get more symmetric curves. There are three
positions for the time constant: 0.1, 1 and 10 seconds. Attack and
decay
times are unknown. I'm missing something: what setting should I choose
to perform the alignment?

Thank you and best regards
Paolo