[WriteLog] What's wrong with AFSK? was - 5 bit mystery unraveled

[Mike]

Hello,

I've been hesitating to jump in on this thread as my sentiments regarding 
AFSK and FSK are the same as George's, W1ZT.  However, since George broke 
the ice, here is my two cents.  And like George described I adjust the 
tones to use AFSK and narrow filters.

The advantage of AFSK to FSK for contesting was recently brought out to me 
while being part of the WPX multi two operation from KM4M (aka K4JA).  FSK 
was used with the FT1000MPs and Orion.  Several times doing S&P the 
targeted station would be good copy, but couldn't be worked.  When 
operating at K4JA and you can't work a station that is good copy after the 
third call you start to wonder if something is wrong.  What was wrong in 
all cases is that I had gotten use to having the Net capability of MMTTY 
with AFSK at the home QTH.  At K4JA the xmit. freq. was off enough for the 
targeted station being able to copy others better.  This was noticed the 
most with 500 Hz filters.   Only noticed it once or twice using the 250 Hz 
filters.  Yes, in all instances once the xmit freq. was readjusted, the 
target station was worked.

Regarding spotting; listening and tuning are required.  In addition to 
George's spotting comments, another situation requiring listening and 
tuning is when a rare DX station/mult. comes back to my CQ.  I'll spot him 
at 14080 kHz for instance if it is the 20 meter band rather than on my 
calling freq.  This type of spot is to let others know that the rare 
DX/mult has been heard on the band, but is doing S&P.

Having followed George with my similar comments, please flame him and not me
At 05:28 PM 3/1/04, George Johnson wrote:
>Time to weigh in with a "minority opinion":
>
>For all the reasons previously described, I would like everyone else to 
>use FSK.  I don't want to hear spurs.  And I don't worry about your loss 
>of high pitch hearing as long as you tune in my signal properly and print 
>it accurately before you call.
>
>I use AFSK with autotune.  I get to use low tones centered on my 
>adjustable narrow receive filters. With auto tuning I catch you quickly at 
>the end of you CQ... (you do put CQ at the end of your call sequence), and 
>I call you on your frequency.  My autotune decoding adjusts my receive and 
>transmit between your 165 Hz shifts and 205 Hz shifts accurately every 
>time.  When you call me off frequency I hear and decode you quickly in a 
>pileup.  You answer me quicker because I call you on frequency in your 
>passband.
>
>And I don't care if your DX spot is 2KHz off because I listen to the 
>station before I call him.
>
>I believe that the same care and knowledge in setting up and tuning an FSK 
>transmitting station properly requires skill similar to setting up, tuning 
>and operating an AFSK station.  Most of the rest is just personal preference.
>
>My 0.02 worth,
>73, George .. W1ZT
>
>At 02:47 AM 3/1/2004, you wrote:
>>It seems to me that the cognoscenti prefer FSK to AFSK.  I have never 
>>seen any reasons for this preference, probably because I haven't looked 
>>in the right place.  So, what's the problem with just sending AFSK to the 
>>radio, thereby eliminating the need for an AFSK to FSK converter?
>
>
>
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         73,
         Mike, K4GMH