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[TenTec] One last chirp

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Subject: [TenTec] One last chirp
From: geraldj@ames.net (Dr. Gerald N. Johnson, P.E.)
Date: Thu, 07 Jan 1999 18:43:42 -0600
I listened to the beginning of 0000Z code practice. I still can't find
anything but a hard leading edge. Its most pronounced with the signal
nearly centered in the SSB filter, least pronounced with 500 Hz CW
filter shifted to pass only up to 800 hz and a passive 990 Hz LC low
pass filter on the speaker. Oh, the receiver is  Corsair II.

Which leads me to suggest that the shift is OK on the BFO, what's needed
is a millisecond or two of transmit power delay after key closure and
then a slightly gentler slope on the rise of that transmit power. That
gives the BFO a millisecond or two longer to settle and cuts the hard
leading edge.

This hard edge won't show on a lot of radios because their crystal and
mechanical filters have a rotten time response and so are slow to start
(and ring to fill in the holes between line noise pulses as well as
lightning crashes). The TenTec filters seem to have a better time
response so make the hard leading edge of the Omni VI really sound hard.

You can't judge leading clicks with fast TenTec AGC, its best judged
with AGC turned off and manual RF gain because on FAST AGC TenTec
receivers make their own click on the leading edge.

73, Jerry, K0CQ

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