I used to struggle with converting from cps to wpm until one day my 
brain actually kicked in and I made the association this way:

cps x 60 seconds / 6 characters per word = wpm

Therefore,  if 120 cps x 60 = 7200 / 6 = 1200 wpm

Thus,  to convert from cps to wpm, just add a zero.

To convert from wpm to cps remove a zero.

But it also means that your can roughly estimate wpm as being similar to 
the bps rate unless you are doing FEC and other coding:

Thus 1200 bps ~ 1200 wpm.

But because of overhead, I usually round a byte up to a nice even 10 
bits so I would agree with using a slower value such as your 120 cps.

Seem reasonable?

73,

Rick, KV9U




Walt DuBose wrote:

>How can 1200 baud = 1320 WPM?  In the case of AX.25 baud=bps since a 
>mark-space=one bit.
>
>An 8 bit ASCII character with start and stop bits would be 10 bps so 1200 
>bps=120 CPS.
>
>If a word is 6 characters, then 120 CPS = 20 WPM which we know is too slow.
>
>As far as a mode using a VariCode, the WPM throughput would normally be 
>expected 
>to be one CAP for every 60 lower case characters.  That's less than 2% caps so 
>I 
>would think that you would get close to 190 WPM (maybe as low as 180 WPM) in a 
>200 WPM mode using the VAriCode such as used in PSK125.
>
>I would assmue that on keyboard-to-keyboard QSOs that the robustness would be 
>more of a concern than the throughput.
>
>73,
>
>Walt/K5YFW
>
>  
>

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