[TenTec] One last chirp

Paul Christensen paulc@mediaone.net
Fri, 8 Jan 1999 17:25:08 -0500


>I don't think its the placement of the transmit BFO frequency in the
>filter, I think its overdriving the system and thus negating the keying
>shaping by the ALC.

I looked at this early-on in the investigation.  The bottom line is that BFO
frequency placement within the filter's passband is a dominant factor.
Either by keying in the FSK mode or deliberately shifting the CW transmitted
BFO frequency above 9,000.400 cures the problem.  If overdrive is prevelant
at 9,000.400 kHz it would be more than prevelant at 9,000.600 kHz, where the
Omni Six is chirp-free.

>A little more rise time on the CW keying envelope with maybe a few
>milliseconds delay from shift to the rest of the radio being keyed on
>should also help.

Yes, considerably.

-Paul, W9AC




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