[Milsurplus] [ARC5] 1625 and Key Clicks.

[Bob kb8tq]

Hi

Time constant - how fast do you normally send? 

10 WPM is 50 characters per minute or about one a second. With normal 
spacing, you are at a character in a second. 

If you send a series of numbers, you have about 20 elements per second. Normal
letters will be a bit less. 

For reasonable “fidelity” you want a time constant / filter that will pass the 5th harmonic
of your keying “square wave”. That gets you to about 100 Hz or so. 

This all scales with keying speed. If you normally send at 100 WPM, 100Hz becomes 1KHz. 
None of it is exact. You could go to “3rd harmonic” and cut them 2:1. …You could go to the 
9th harmonic and double the targets. It still works either way.

Bob

> On Jul 11, 2017, at 12:26 PM, arc5 at ix.netcom.com wrote:
> 
> Has anyone here figured the correct 
> R and C for a Key Click Filter at the
>  keyed cathode of 1625s? 
>  If not, does anyone have a handle 
> on the correct Time Constant 
> to do a little wave shaping? 
> 
> I could "by guess and by golly" with a 'scope, but surely someone has already
>  done this.  ("And don't call me "Sherrly!")
> Thanks, 
> Dave S.
> 
> Sent from my Ain't Smart Phone.
> 
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