Well Stefan , better the dsp engine respond
Only problem
8970 is out side the decoder pass band ,
if qrg can be changed to 8912.5 +/- 12
Hz then no problems
To date , there have been various
garden gate tests and ground testing in USA ,
but as yet, no real long range AIR-Test , in this case
the sound card is acting as SDR with
no need for additional frequency adjustment.
Due to the long 4 hour 50% duty cycle OP4H
shows on Spec lab qrsss giving a
second chance at observation
Tx drive is per normal, with
direct 8KHz audio keyed and COM-Port
CW keying
[ decoder pass band is centred on
8912.5 Hz with +/-
12.5 Hz window , giving 8900 <> 8925 Hz]
Normal sound card stability is required , the
Tx audio drive is centred on 8912.5 ,
with carrier avoidance , Rx input is direct
at 8900 <> 8925 Hz ,
The lowest decode to date showing at -49 dB
on the Op scale ( calibrated to path-sim software)
Note , Op4H is still a data mode
and not a carrier detection system and still
capable of multi Tx decodes , normal web
linking is provided and PSK-Reporter has
a 'VLF' band , Marcu's
correlation system should give lower s/n as
well ?
Latest version of OP available for
download has the 8K band qrg corrected in
the listing and w/fall ,
73 -Graham
G0NBD
Sent: Thursday, February 14, 2013 12:12 PM
Subject: Re: LF: Re: 8970.022 Hz
Uwe,
Solid signal since several days! What about
some special tests, like WSPR-240 or so? Of course G.. would love OP4H (bet he
will respond to that :-) ).
The WX is dry and sunny now and i begin to
get some "spring-feelings" and think about a VLF test again... I hope to
remember how to do it :-)
73, Stefan/DK7FC
Am 13.02.2013
21:13, schrieb Eike Katzera:
Hello Uwe,
I am interested in descriptions and pictures of your VLF transmitter and
your antenna? Do you have any?
73s
Eike DL3IKE
