Hi,all.
To date , not tried a multi tone data system .
The Olivia system , would seem to print well
into the noise ..may out perform psk31
The 'multipsk' software has a 250 x 8 tone
setting 250 hz/bw 8 tone freq , I shall set the 'purple' center freq
marker , to 503.3 dead (+/- few c/s) . the output spectrum looks
quite clean , and should not spread .
There are wider versions , but 250 should be
'ok' --- If anyone is xtal fixed , plse let me know and i can qsy
>>>> Sorry to those who 'know' ,
follows notes on reception <<<<<<
As its possible , from observation at 'HF'
olivia will print from below the noise level , accuate rx seting may be neede
,
rx settings 'usb' - dial frequency
to give recovered audio center frequency to that of the transmission
and software settings
i.e. The tx settings will be -dial
frequency - 502.000 Khz , mode usb .. software tx/rx tone , center
frequency, 1,300 Hz , giving 503.3 'carrier'
The reverse applies for 'rx' dial 502 , usb
, software , -purple mark- 1300 Hz
using a narrow filter should not be needed as
the soundcard/software will provide the slectivity, also narrow filtering may
'round' the pulses and reduce the s/n at the rx .
NB .. The new 'digital master 780' also supports
the mode, but dosent appeare to support the '250x8' narrow version
.. other packages may do.
Software can be downloaded from :-
select :-
Tnx
Graham
G0NBD
io83lk
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