Topband: Re: Key Clicks

[Tracy, Michael, KC1SX]

Paul Christensen wrote:
>
> is this information available in the comprehensive Product Review?

Yes, for a number of months now there have been plots of keying sidebands (+/- 5 kHz) included in the expanded reports.

As to discussions of what sort of waveshapes generate clicks, I have refrained from commenting precisely because of what I've learned in doing this testing.  As it turns out, a rig with an "obviously" good waveshape isn't necessarily good spectrally.

For example, you could hardly ask for a nicer looking shape than that exhibited by the Kenwood TS-940 (reviewed in Feb 86 QST).  As it so happens, the lab owns a TS-940 that is used for some amplifier testing, and I recently performed the keying sidebands test on this radio.  The results were *not* significantly better than other rigs I've tested, including the (stock) FT-1000MP.  

So far, the only radio I've tested that was significantly better was the Harris commercial model that we use at W1AW...  (discounting a couple of units with a slight audio spur problem, which are currently at Harris being serviced).

73, Michael Tracy, KC1SX, ARRL Lab