Topband: More About Clix

[k6se@juno.com]

Virtually all of today's modern rigs have a key click problem.  The stock
FT-1000MP and Mk V CW signal rise time is 2.4 ms and the fall time is 1.0
ms.  This is on every dit and dah.  The ARRL criteria for "clean" keying
is a rise and fall time of 5.0 ms.  After the INRAD keying improvment
mod, the rise time is 4 ms and the fall time is 2.2 ms.  It certainly
improves the keying, but not enough, which is why I'm going to do the
W8JI key click mod on my MP.
 
A friend has an IC-756 PRO which has clicks extending out at least +/- 1
kHz.  Another has a late-model IC-775DSP which has clicks as bad or worse
than the FT-1000MP.  Additionally, you can hear a "thump" on his first
dit or dah when he is operating split.  Earlier model 775s have the
additional problem of generating a signal from the receive VFO when
operating split (becoming worse as the split frequency is smaller),
clearly an FCC violation.  Icom knows about this problem because they
will upgrade the early version if the owner complains, but they won't
publicly confirm this problem.
 
Many topbanders prefer the Omni VI+ because of its superior QSK and
excellent receiver.  But even it has bad clicks.  INRAD has thus far
unsuccessfully tried to develop a mod to correct this.  George, W2UVG
(owner of INRAD) told me, "I have spent many hours working on the Omni
VI+ keying and ALC loop as it has a similar problem.  The keying waveform
out of the first mixer is text book perfect, 5 mS up and down.  Then it
goes through the ALC loop and the output has 1 mS rise time and 5 mS fall
time.  This loop has a very slow decay time, and it doesn't change the
input shape.  If I disable the ALC loop the radio puts out 100 watts and
the keying is perfect.  But there is no power control, etc."

Jim, N7JW has overcome the Omni VI+ click problem by using an FT-1000MP
with the W8JI key click mod to transmit and an Omni VI+ to receive.  It
would be nice if all hams (especially topband contesters) were as
concerned about having a clean CW signal as N7JW is.
 
I'm not sure how the modern Kenwood radios are as far as clicks go.

73, de Earl, K6SE