[Elecraft] "Good QRP practice"?

Fred Jensen k6dgw at foothill.net
Sat Aug 27 18:55:05 EDT 2011


Good question John.  I think Wayne was proposing a "bottom line" 
estimate from a somewhat more complex problem.  There are a lot of 
variables to consider.  Morse code is scaled in dot-times [DT].  Dots 
and inter-element spaces are 1 DT each.  Dashes are 3 DT.  Letter spaces 
are 3 DT, and word spaces are nominally 7 DT [I think I've got that 
right].  At any rate, if you are sending Morse code, all those spaces 
are receive time [and current drain] and only the key down times are TX 
drain.

What that all means in terms of steady keying depends on what you are 
sending of course.  Then there is the really big factor:  When you 
choose to send something vs when you choose to listen.  When you're 
running 5W to a possibly compromised antenna, you will be doing quite a 
bit of listening, finding the right station and right time to call. 
There's no reason to call the station if he's being called by a big gun, 
it just wastes your RF.  The result is, your key is actually down [i.e. 
TX battery drain] in the general vicinity of 10%, give or take.

"Good QRP Practice" may be a little rigid a phrase, you're free to use 
the ampere-hours in your battery any way you choose, but "successful" 
QRP operation does require more listening and timing than 1.5 KW to a 6 
over 6 over 6 over 6 stack on 20 meters.  If that's your station, you're 
pretty much the BGOTB [Big Guy On The Band], everyone hears you.

73,

Fred K6DGW
Auburn CA

On 8/27/2011 3:25 PM, John Flynn wrote:

> I'm really new in amateur radio and even newer (if possible) in working QRP
> with my KX1 and working on my skill set. My question is why is a 9:1 listen
> to transmit ratio "good QRP practice"?


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