[sdiy] Just curious

[jhaible at debitel.net]

Well, I just wanted to point out that diy means a lot more
simulation than actual building for me.
Last night, and the night before, I've made extensive simulations
about how a compander would, or would not, mess with the purity of
frequency shifting in a single sideband modulator.

There's a dilemma:
If it wasn't for the dome filter, the multiplication with
sin and cos of the carrier happens instantly, so I could
use very fast compander time constants, and use the CV of the
compressor to control the expander.
But with the dome filter's frequency dependent delay (up to
16ms at the low end of the audio range), very strange things
happen in this setup.
I could use a compressor with two VCAs, after the two dome filter
outputs, to avoid this. But these would have to be terribly 
precise in tracking, in order not to unbalance the SSB modulation.

I can spend hours and hours on things like this. Much of it is
discarded later, and you won't see it in the final circuit ...

JH.



> ok then add about another 3 hours for simulations for me... but those 
> might be outside of what
> might be considered DIY time...
> 
> H^) harry
> 
> 
> JH. wrote:
> > About 5 ... 6 hours of PSpice simulations
> >
> > maybe 2 hours soldering
> >
> > 5 hours playing
> >
> > JH.
> >
> >
> >
> >   
> >> How many hours a week do you guys "work" on your modular/instruments?
> >> And how many hours a week do you make music with your
> modular/instruments?
> >>
> >> Just curious..... and checking out how crazy I am ;-)
> >>
> >> -- 
> >> Tom Adam
> >> The Big Ear
> >> http://users.pandora.be/the-big-ear/
> >> Check out the download section!
> >>
> >>
> >>     
> >
> >
> >
> >   
> 
> 
> 




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