[Elecraft] Another urban legend: clicks needed for readability

[Guy Olinger, K2AV]

W8JI, who is the main author of bandwidth mods for clicky Yaesu rigs,
did extensive studies with some friends in weak signal/noise
conditions on 1.8 MHz.

One comparison was using a bandwidth modified FT1000MP randomly
interchanged with a very sharp unmodified one. The power level was
reduced until some difficulty in copy was experienced at the far end.

Various DX operators were UNABLE to detect when the rigs were
switched.

The reason why this is so is that the actual power in the bandwidth
necessary to produce a "sharp" sound drops quite far into the noise
when the main signal is at or in the noise. Same reason why the K2's
clicks never bothered QRP operations.

Tom's experiments with various shapes to the rise and fall had no
apparent effect on readability.

Not to put down personal taste at all, but one's preferring a sharp
clicked signal over a "mushy" signal is just exactly that, personal
taste.

Gentlemen's CW signal spacing in radiosport is 500 Hz. That means that
+/- 250 Hz belongs to you, and anything beyond belongs to your
neighbor. Personal taste or not.

However, the modified K2 I listened to did NOT sound mushy.

The objectionable clicks are caused by sharp turns at the transition
extremes, NOT by the rise times. Each dit or dah has FOUR of these,
"off to rising", "rising to on", "on to falling", and "falling to
off". Wayne has fixed the two of the four that were sharp, without
doing much that I can see to the rise and fall times.

The new slight extra delay (2 ms?) from key to RF rise, and matching
baud-end persistence, will help people trying to drive amps with K2's.
This is installed as a FEATURE in some high-end rigs to help keep from
frying amp changeover relay contacts.

Would point out that TenTec has been fairly blasted by it's own
customers about the clicks in the Omni 6+ which many have labeled
retrograde and worse. It is being referred to by TenTec as an
unintended error copying forward circuit design from the clickless
plain Omni 6. So perhaps not a good idea to elicit comparisons to that
rig as state-of-the-art in bandwidth.

Wayne's solution, by its very simplicity, proves that there's really
no excuse for not fixing the clicks. It will also very quickly put an
end to the urban legend that signals have to have a sharp wideband
click on them for readability.

Of interest, in modifying MP's for keyclicks, one of the problems
encountered is that some components used in these circuits are often
manufactured with a tolerance of -20/+80% (!!!). There are some
original condition MP's (I know of one around here) that sound nowhere
near as bad as the general case. When is a .01 not a .01? Maybe the
whole thing was a supply problem?

Yet another agitation we don't have to worry about getting our stuff
from Elecraft. Thanks to the guys for doing great work.

73, Guy.