[600MRG] WSQ - A Weak Signal QSO mode for LF/MF [-25dB snr]

Brian Pease bpease2 at myfairpoint.net
Wed Feb 11 09:23:40 CST 2015


I forgot that there are capitol letters.  Try 
http://www.qsl.net/dl4yhf/WSQ/index.html
On 2/11/2015 10:18 AM, Neil Klagge wrote:
> Brian, that link did not work. "Error 404, page not found"
>
> Sent from Neil's iPhone
>
>> On Feb 11, 2015, at 07:07, Brian Pease <bpease2 at myfairpoint.net> wrote:
>>
>> I have done some bench testing of a WSQ2 link with real atmospheric noise bursts.  The mode really works down to its -25dB limit.  The best thing about it seems to be its ability to sync & re-sync quickly after a drop out.  Remarkable performance considering that it is not time-synced and has no forward error correction or fancy coding and does not require precise tuning or post processing. Being a 1 tone at a time FM mode, it is bothered by continuous tones within its receive bandwidth.  I recommend the "enhanced" version of WSQ2 by DL4YHF at qsl.net/dl4yhf/wsq which has a squelch setting, adjustable audio tones, a spectrum line during receive, AGC on/off, etc.
>>> On 2/11/2015 6:48 AM, Ralph Wallio, W0RPK wrote:
>>> http://www.qsl.net/zl1bpu/SOFT/WSQ.htm
>>>
>>> Amateur Radio enthusiasts who are interested in the LF and MF bands will be familiar with WSPR. Used as a propagation probe or beacon, WSPR allows very weak signals to be detected, frequently as weak as -27dB SNR or lower. However, once you have established that a signal path exists, how then do you hold a QSO?
>>>
>>> But what QSO mode matches WSPR for sensitivity?
>>>
>>> WSPR is not a QSO mode, and is very slow, so you cast around for something else - to find that no 'chat' modes offer performance anywhere near the -27dB sensitivity of WSPR. Not Morse, PSK31 or even CMSK will reach this sensitivity. Even DominoEX4 will only manage about -18dB SNR. The best offering is JASON, with a sensitivity of about -25dB, but it is
>>>
>>> V... E... R... Y...     S... L... O... W...
>>>
>>> How frustrating!
>>>
>>> So, Con ZL2AFP and Murray ZL1BPU decided to do something about this problem - to take on the challenge to design a QSO mode capable of sensitivity performance near that of WSPR, and much faster than JASON: fast enough to allow real QSOs. To do this required a completely new approach. Using a new IFK design with more tones, plus text compression techniques, we have achieved not quite a comfortable 'chat' speed, but at least enough typing speed to allow contact and to exchange information within a few minutes. Novice CW operators have been doing much the same for decades (although not at -25dB SNR!).
>>>
>>>
>>> _______________________________________________
>>> 600MRG mailing list
>>> 600MRG at w7ekb.com
>>> http://w7ekb.com/mailman/listinfo/600mrg_w7ekb.com
>>
>> _______________________________________________
>> 600MRG mailing list
>> 600MRG at w7ekb.com
>> http://w7ekb.com/mailman/listinfo/600mrg_w7ekb.com
> _______________________________________________
> 600MRG mailing list
> 600MRG at w7ekb.com
> http://w7ekb.com/mailman/listinfo/600mrg_w7ekb.com
>





More information about the 600MRG mailing list