Well, I guess it's time to determine exactly what the Omni VI+ audio
chain in receive really is. Guess I'll have to make frequency response,
slew rate, THD, IMD and s/n measurements.
I figure from the circuit that there's some roll-off to kill the hiss.
The way it's done it may cause IMD to be a bit high thus producing a
"non musical" character to the RX audio. Harmonics of 3rds, 5ths & 7ths
are fine where as 2nds, 4ths, and 6ths are not.
More latter.
73
Bob K4TAX
John Pritt wrote:
>
> For all you contesters and operators alike, remember that the filters in the
> Omni 6 are cascaded. What this means is in achiving higher fidelity, you
> loose selectivity! With the stock 2.4 filters, that come standard with the
> rig, plus any that you add to the 9 and 6.3 mhz filter positions, these are
> all cascaded to provide extremely excellent steep filter walls. This is just
> what the doctor ordered for phone contesters and DX chasers....minimal QRM
> from outside the passband. I can even remember those who talked about how
> nice it would be if the roofing filter could be replaced with a 2.4 mhz
> filter! But....if you are a ragchewer and QRM is not a factor, then this
> Inrad mod is for you.
> 73.........John
>
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