Re: Order for V/F's

[mooney@aps.anl.gov (Tim Mooney)]

re...

> Regarding that high linearity Nova N101VTF V-f converter, it's got a
> 'feature' that instantly meets opposition:  each of the four channels
> have gain knobs on the front panel that can be set to x1, x2, x5, or x10.
> 
> Now how the blue blazes are we going to get those knob settings logged
> into our data files?  Preset them and cut the knobs off?
> Fancy ^&%$%$#@ computer control system and we get this to write down!

Three comments:

1) It's actually worse than you've described, since there are two
internal switches per channel: 5V/10V full scale, and +/- input
polarity.  But since these are internal switches, it's probably ok not
to log them.

2) If you want automatic logging of the gains badly enough, it can be
done.  In the V/F's we received, at least, the front-panel gain
selection is actually implemented with a two-pole switch, one pole of
which is unused.  It wouldn't be too hard to mount a connector on the
back panel and export the states of those switches.  You might even
persuade Nova to do it for you, if you say plea$e.  (However, they may
have chosen a different switch since our order was fabricated, since we
did not specify a two-pole switch, and since they're heavily into cost
reduction these days.)

3) As I mentioned in last posting, Joerger is interested in producing
VME-based V/F converters.  These would presumably be loggable.

Tim