Sorry Rick, I don't have the spec for PSK31, but common practice
requires that your signal vary only a few Hz (if at all). In fairness,
there are instabilities in sound cards that can cause drift too.
Another benchmark is to speak with the ESSB guys on 3615 or 14.178. I
believe you will hear from them that any drift greater than a few Hz is
immediately noticeable from their perspectives and trained HiFi ears.
Alan Davis K2WS offers an OCXO upgrade for the Flex-Radio SDR-1000 for
just that reason: http://www.n9vv.com/K2WS-OCXO.html
How about if you are transmitting into a TRANSVERTER that gets you from
10M to 10Ghz. I wonder what the 50hz drift could be, when multiplied by
the Ghz equipment?
Ken
Rick Westerman, NJ0IP wrote:
> OK Ken, but please define "stable".
> 50 Hz in 15 minutes is surely not too bad, is it?
> And if I understood the original post correctly, after 15 minutes warmup
> things are OK.
>
> Is there a spec on stability requirements for PSK31?
>
> Tnx
> 73
> Rick
>
> Ken N9VV wrote:
>
>> PSK31, Olivia, and other digi modes DEPEND on stable signals on both
>> ends. Old time boat anchors are not generally used on digi modes due to
>> their drift and instability.
>> Ken N9VV
>>
>> Rick Westerman, NJ0IP wrote:
>>
>>
>>> Maybe I'm missing something, but could someone explain to me why I need
>>> to fight a 20 Hz drift?
>>> Seems like you guys are brainstorming a lot of ways to spend excess
>>> money when my solution would be to turn the radio on a little earlier.
>>>
>>> I remember the days we used to have to chase people with drifting VFOs
>>> and now we are worried about 20 Hz.
>>>
>>> 73
>>> Rick
>>>
>>>
>>>
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