My exact issue when looking at S/N generators -- the analog part.
Which is why I am about to build a 2-3kHz bandpass filter and switch
to looking for low averaged values by less integration (shorter delta
t) and faster sampling in the ADC to look for "valleys" in a "better"
way. Make any sense at all?
On Jun 20, 2008, at 10:23 AM, Jeff DePolo wrote:
> You mentioned a re-write of the LDG software. Would you be
> willing to share whether or not you changed what the
> processor is looking at from the ADC to consider a channel to
> be the best? What intrigues me most about the LDG is that the
> difference between being a straight S/N voter and a "valley"
> voter is only software.... or some mix, or both, etc.
No, the software still uses the same DC sample from the noise
filter/integrator in the same way. However, it does make significant
improvements in what is done with the A/D values via math, much of
which
involves user-adjustable parameters.
The problem many people run into when trying to balance a voted
system is
that the local receiver is always the odd duck because it will
present more
high-frequency noise than will receivers that use RF links back to the
voting comparator. Improving the noise filter in the voter such that
it
looks at a narrower spectra for noise helps that problem (i.e.
instead of
just a high-pass filter, bandpass). The most effective outboard fix
is to
simply EQ the local receiver so that its high frequency response
closely
mimics that of the other receivers audio is passing through the RF
link
where additional HF attenuation is incurred.
--- Jeff
--
Cort Buffington
H: +1-785-838-3034
M: +1-785-865-7206
