Re: PSK31 split operation


Stephen Melachrinos <melachri@...>
 

George -

Avoiding distortion is always a good thing, but I haven't seen PSK31 get distorted enough near filter-band edges to lose decode. I lose the signal power before I see a distortion.

Perhaps the m-ary FSK underlying the JT modes is more sensitive than PSK.

And remember that with splits in the few hundred Hz, proper positioning of your signal (as Eric suggested) should keep the received signals away from filter-band edges.

Steve
W3HF


-----Original Message-----
From: George Weller <gvweller@...>
To: main@070Club.groups.io
Sent: Fri, Jan 14, 2022 7:09 pm
Subject: Re: [070Club] PSK31 split operation

That's helpful gents. Thank you.  A pile-up is one thing and I can see
the reasoning on that.  On wsjt-x, the rationale is that the Tx signal
is narrow band; minor distortion (near the edge of the Tx passband
filter) reduces likelihood of a decode, so wsjt-x sets the split and
adjusts the audio offset so that the Tx is at the exact same frequency
as Rx, but is now in the center of the Tx passband. It seems like the
same logic would apply to any narrowband signal. Of course, as was
pointed out, the PSK band is usually not crowded and you can pick a
frequency in the middle.

73, George KD9PCN

On 1/14/2022 12:56 PM, Eric KG6MZS wrote:
> On 1/14/22 9:07 AM, Stephen Melachrinos via groups.io wrote:
>
>> The only times I've ever operated PSK split were when I was
>> (semi-)rare DX and I had lots of stations calling.
>
> I'll echo Stephen's sentiments.  I've seldom needed to use split for
> PSK because the PSK waterfall just isn't that crowded.
>
> In Digital Master 780 it's pretty easy to set up split.  Just set up
> on a clear frequency and lock it, then move the receive cursor over to
> the station you want to work.  I usually center my TX frequency in the
> waterfall.
>
>
> 73
>
> Eric KG6MZS
>
> www.kg6mzs.com
>
>
>
>
>
>






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