Its difficult Stefan , in this case its a
engineering beacon , that measures the path in
terms of average signal and % fade ,
the s/n determines the max data rate
the link will support and the % fade , indicates
the interleaving requirements , interleaving
bridges the qsb 'gaps' but , then slows the
turn round time ..... better to have a
good level of sensitivity and longer
interleave on MF , as the time to send the
message at 100% error free may seem longer ,
but , if bits are missed , then time
is lost in re-tries .same with arq ,
repeats slow the transfer down
Yes its exchanging call and s/n reports
, linked to the psk-map and other users as a
complete system , that also seems to meet the minimum
requirements of a 'qso'
For a live qso
Version 1-4-1 supports 15 chrs plain
text , and sends in 60 seconds , using
single tone , which can be used for
a live qso , enough
to exchange info like ' I have a cat' etc ,
but it needs round -20 -23 dB s/n
to decode , which is simple to reach on HF ,
reasonable on MF and not so easy on 136
You could reach levels over -20 into
the Uk etc , but , the problem is , how many
stations do you see at over -20 in
rx on 136 ?
Ros-mf-2 works at -24/25 dB s/n and is
a full free running data mode , mf-7 runs at
the same speed as psk31 and is about
10/12 dB lower s/n with interleave , and can be used
upto 28 MHz .. but is multi tone , so needs
additional hardware
The Opera one4one file can be downloaded
from :
https://groups.yahoo.com/neo/groups/O_P_E_R_A_/files,
note , the coded frequency is 500KHz , from the
time it was developed , set 477 usb
now ! and there is no 136 allocation for
qso ,if anyone wants to try 2 way on 136
just use '500'k
73-G,
Sent: Wednesday, March 19, 2014 10:01 PM
Subject: Re: LF: It CW MAL , But not as most know
it
...hmmm, and even like some CW QSOs heared on HF, just exchanging
callsings and report via internet? Automated report and serial number via PC in
300 bpm, "5nn"?
Not really CW, isn't it?
73, Stefan/DK7FC
Am
19.03.2014 18:58, schrieb Graham:
It CW MAL , But not as most know it
Opera Op0.5 30 second TX
cycle -20 dB s/n min decode
A Magic mode for the Magic band !
G, ))
