> The problem is the radios. The response time of external ALC ports
> is generally far too slow.
It seems designing an accurate transmitter ALC system is more art than
science. If the ALC is too fast as in the stock Ten-Tec Omni Six, one
encounters leading edge envelope distortion, particularly manifested during
CW as hard keying and key clicks may be present in extreme cases. If the
ALC acts too slowly, power spikes becomes evident at anything less than full
transmitter output power.
Three years ago, I modified my Omni Six such that the keyed envelope is
symmetrical at all power levels and no overshoot is evident. It took me
three straight weeks of experimenting with a 2-speed ALC circuit to get it
right...one of the most painful, yet rewarding experiences of my life.
-Paul, W9AC
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