[Elecraft] K3 fsk D splater

[Rick Bates]

I answered Adrian off list.  The topic read PSK not FSK at the time.  This
is what I had sent:

-=-=-=-=
PSK is not key shifting.  That is FSK.

PSK involves more than two unique tones, which means audio (phase) shifting;
both on sending and receiving.  It may be hidden in the -D modes, but audio
is still en/decoded.  The same is true for FSK (RTTY) decoding; the DSP
detects the tones and durations to effect decoding.  Ditto CW decoding.

Only the K3 and a couple other radios can do this with no other software so
most folks use a soundcard.  I use a soundcard most of the time so I can
watch the entire audio band for the station(s) I want to work.  We're
fortunate that we have the digital mode ability in the K3.  I've only used
it a few times, pretty cool feature.

If the transmit audio and/or the receive signals are flawed, the
transmission won't be properly decoded.

If you can get a fine enough resolution on the P3, you can see the flaws,
but most people use software which gathers the data from a soundcard.  And
properly setting those up appears to be more than some folks understand.

Many soundcard folks overdrive their audio into their transmitter and others
overdrive the soundcard from the receiver so the signals appear faulty (when
it might just be the receiving station).  If everyone (soundcard users)
carefully set their levels, there would be fewer complaints.  However, once
a soundcard is properly set up, it's easy to see how many 'bad' signals are
out there (quite a few).  

Others complain of folks running too much power, but that isn't a factor;
signal cleanliness is the issue.  I defy anyone to tell how much power is
coming out of a clean station, be it 1/10 watt or legal limit.  Signal
strength isn't even a valid test because it could be band conditions,
transmit and/or receive antennas or many other things.

i.e. What's the difference from 100 watts into a dipole versus 10 watts into
a 4 element beam?  Answer:  Not a darned thing except the beam focuses the
energy.  The inline signal strength is exactly the same.

Most also have no clue how to notch out or otherwise remove LOUD signals
(tripping an ALC response) so they can copy the weaker ones.  The K3 makes
this simple too; adjust the hi/lo cut, narrow the bandwidth or use the notch
filter manually.  Or do all three.

Gee I like the K3; they thought of everything except the operator who
understands how to USE what they've built.  I'm getting there.  ;o)

-=-=

So now all y'all know what he meant.  Yes, it may be over simplified, but
that's how I like it.  ;o)

Rick wa6nhc

----Original Message-----
From: elecraft-bounces at mailman.qth.net
[mailto:elecraft-bounces at mailman.qth.net] On Behalf Of vk4tux
Sent: Wednesday, May 30, 2012 5:19 PM
To: elecraft at mailman.qth.net
Subject: Re: [Elecraft] K3 fsk D splater

Yes you are right Rick, let fix the OP's subject error listing.
RTTY FSK-D is the mode tried right ? Mark and shift, shift keying 
ascii ky keying from the k3 via K3 utility or Kcomm.
I dont know how I let myself repeat the psk-d rubbish, but I am a very
naughty boy.

Adrian ... vk4tux

--
View this message in context:
http://elecraft.365791.n2.nabble.com/K3-psk-D-splater-tp7556767p7556824.html
Sent from the Elecraft mailing list archive at Nabble.com.
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft at mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html