[Elecraft] CW rise time mod

[Vic K2VCO]

David Pratt wrote:
> Elecraft says.....
> "Some owners prefer a faster CW keying waveform rise time. The rise time 
> can be reduced from about 8 milliseconds to 5 milliseconds without 
> affecting the fall time by replacing capacitor C222 on the K3 main RF 
> board with a 0.1 uF capacitor. This change will also allow a future 
> firmware revision to further reduce rise time via a menu entry."
> 
> But the schematics of the RF Board Rev. A4 (Sheet 3 of 4), dated 
> 9/19/07, show C222 as being 0.1 already.  The instructions recommend 
> removing the existing 0.1 and replacing it with another 0.1 !!  Surely 
> to reduce the rise time the existing capacitor should be shunted with 
> another one.
> 
> Or do Rev A RF boards have a lower value for C222 than that shown on the 
> schematic?

As I understand it, Wayne called for the modification earlier, but for 
some reason it didn't get reflected in production. That's why the 
schematic doesn't agree.

The old value was 1 uf and it the new, correct value is 0.1 uf.
-- 
73,
Vic, K2VCO
Fresno CA
http://www.qsl.net/k2vco