[Elecraft] Change to Elecraft Keying Mod

Mon Mar 29 00:04:01 2004

I have looked at the waveforms you show on the website below.

I believe the best way to interpret the results would be to presume
500 Hz channels, and look at the highest power presented in each
channel to get an idea of the click power in each. Seeing how close in
clicks disappear is a slyly deceptive indicator for best improvement.

The adjacent channel would then be 250 - 750 Hz, with the co-adjacent
channel at 750-1250. For a sloping curve across the bandpass, the
total power in a channel will be controlled by the high end of the
curve.

That gives the following results:

mod                250-750       750-1250

orig (red)          -32            -54

elec (blue)         -46            -62

WX   (green)        -40            -73

While you have improved the results at some points by ten db, these
are in the LESS AFFECTED co-adjacent channel.

In the most affected channel, the adjacent channel, results are WORSE
by 6 db.

Since the worst click problem for any rig occurs in the ADJACENT
channel, that is where the FIRST effort must go, as Wayne has
targeted.

What would be more useful is if you could improve anywhere WITHOUT
trading away anything in the 250-750 range. The next guy up or down is
the one getting the maximum discomfort from our bandwidth.

I would also point out that I think some of the modified K2's rigs I
have heard are better than your blue curve. Wonder if there is an
alignment issue, like for the little chirp.

73, Guy.

----- Original Message ----- 
From: "John, KI6WX" <[email protected]>
To: <[email protected]>
Sent: Sunday, March 28, 2004 5:03 AM
Subject: [Elecraft] Change to Elecraft Keying Mod

> I did some experiments on the Elecraft Keying Mod and found a way to
change
> it so that it has a faster risetime with a narrower signal
bandwidth.  This
> should result in fewer key clicks with this version of the mod.
Details are
> posted on my web site at:
> http://home.pacbell.net/johngreb/KI6WX.html
>
> -John
>  KI6WX