> The clicky rig was an Icom IC-7800. The factory default menu setting is
> clicky. You IC-7800 owners should set the menu item for CW rise time to
> max to get rid of your clicks. 73, de Earl, K6SE
Key clicks coming from the 7800 are almost surely the result of ALC
overdrive -- which can produce a hard leading-edge The 7800 incorporates a
front panel "Drive" control. Proper setting in CW is to ensure that drive
occurs at the ALC threshold and no more. If the drive is adjusted into the
ALC limiting range, the 7800 is certainly capable of producing objectionable
key clicks. But if drive is properly adjusted, keying is exceptionally
clean.
It's the classic case of trying to design a radio with a fast enough ALC to
prevent leading-edge power spikes when power is adjusted for less than
maximum, but not so fast as to desecrate the leading edge of the transmitted
waveform. At least Icom provides this control on the 7800. Most other
radios are designed with "compromise" ALC circuits.
Paul, W9AC
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