Communications audio isn't full and robust. It has a limited bandwidth
by the IF filters and proper audio to limit you hearing atmospheric and
circuit noise, hum, and rumble. Adding bandwidth to any of these reduces
the S/N of the desired signal and allows you to filter more atmospheric
and circuit noise and QRM with your ears.
I often use a passive low pass filter on the speaker to reduce filter
leakthrough and audio state high frequency noise outside the IF filter
pass band. One I use is described at:
http://www.geraldj.networkiowa.com/papers/speakerfilter.pdf
Its really handy for cleaning out DSP artifacts.
73, Jerry, K0CQ
On 2/6/2011 8:31 AM, yash@aol.com wrote:
Have been using my ,new to me ,Omni VI+ for a few weeks,like the rig,hard to fault for
a 10+ year old rig. I have one problem that I would like to change. The audio quality. In
stock form the rig sounds "nasally" to me ,constricted and choppy. I installed
the Inrad audio kit ,2 caps and 1 resister,it made a nice change in the quality of the
audio. I noticed that INrad also mentions changing the OEM 6 MHz filter with a #755 of
their design. Has anyone done this filter change? Is there another route to getting the
audio sounding full and clean with this rig? Other than the audio the VI+ is great.
thanks
dale wt4t
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