Bob, I took a look at the transmitted audio spectrum of the Argo 5-watt
version of the Scout yesterday using the SpectraPRO analysis program. The
audio is rather on the low-frequency side with a pronounced "hump" in the
response from about 300 to 800 Hz, flat more or less to about 1500 and then
tapering down about 10-15 dB to 2500 and nothing above that.
If that reflects what the Scout does, then any EQ or mic change that would
reduce the low-end range by about 10 dB and increase the high end about
5-10 dB above about 1500 Hz would seem to be an improvement.
Bob Heil tells us that we need a rise of about 5 dB or so in the (roughly)
1000 - 2000 Hz range for best intelligibility.
My bottom line is that the radio is inherently incapable of transmitting
the low frequencies and extended high frequencies that are the earmark of
the hi-fi signals. I would suggest that you attempt to smooth out the
response by reducing the low end response and boosting the high end and
placing a "hump" in the mid-range.
A Heil HC-5 mic element would probably do wonders for improving the sound
with no additional EQ required. Detail on the Heil website at
http://www. heilsound.com
73/72/oo, George W5YR - the Yellow Rose of Texas
Fairview, TX 30 mi NE of Dallas in Collin county EM13qe
Amateur Radio W5YR, in the 56th year and it just keeps getting better!
QRP-L 1373 NETXQRP 6 SOC 262 COG 8 FPQRP 404 TEN-X 11771 I-LINK 11735
Icom IC-756PRO #02121 Kachina 505 DSP #91900556 Icom IC-765 #02437
robert k stephens wrote:
>
> Tnx for your explanation. I'm beginning to understand that regardless of
> what mic or EQ unit I buy, the Scout may not be quite capable of the crisp,
> clean, top drawer communications audio that I desire. There is nothing
> really wrong with the Scout's transmit ssb (it is after all only a small
> inexpensive portable rig and I have been expecting too much from it) but I
> would like something better. Eventually I'll want to upgrade to another rig .
>
> On the other hand it still is my understanding that the Scout produces a
> not perfect but pretty darn good cw signal . My cw friends think I should
> spend more time with the dits and dahs anyway <grin>
>
> tnx
> Bob KB1CIW
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