>
+2 dB 20% Fade , must be a short tx
?
15:34 8 DJ8WX de DJ8WX Op4H 0 mi +2 dB F:20%_End in muensterdorf with
8w + L, 300m
G,
Sent: Monday, December 30, 2013 3:01 PM
Subject: Re: Re: VLF: Uwe Opera-4H
Uwe
Well that's the first past the garden
gate ! unless the drive is 3Kmt
long hihi
Fade shows 32 % ? that's
only 2/3 of the tx time line ,
was the Tx stopped ?
still at -2 dB s/n thats still ~ +48 dB qro
!
73-G,
Sent: Monday, December 30, 2013 2:46 PM
Subject: Re: Re: VLF: Uwe Opera-4H
HI Peter,
I changed the TX QRG to 8912.5Hz running SpecLab in Op-4H
(ASK0) mode and made a first test with positive result.
the RX was located in 3km distance - Opera v.1.5.0 , RX aerial a 10m
wire connected to the soundcard.
TX output pwr about 1W. pse see:
http://dj8wx-dl.de/opera3.jpg
I think we should have a try as you are my nearest station
rxing VLF.
Now Im increasing the PA output pwr to 500Wrms.
GL
Uwe/dj8wx
Von: [email protected]Gesendet: 29.12.2013 09:45 An:
[email protected]Betreff: Re: VLF: Uwe Opera-4H
Hello Uwe, Markus, VLF
Nothing was seen or detected here from
your transmission in OPERA mode either.
No recognizable trace at
all.
While you're continuous unmodulated
signal almost overloads my soundcard input.
73's Peter - PA1SDB
----- Original Message -----
Sent: Saturday, December 28,
2013 9:08 PM
Subject: Re: VLF: Uwe
Opera-4H
yes Markus, I have had the screen showing the SecLab components
in my focus whilst doing other jobs - for hours.
Now the carrier only mode is on the air.
Until next test
GL
Uwe/dj8wx
Von: [email protected]Gesendet:
28.12.2013 19:07 An: [email protected]Betreff:
VLF: Uwe Opera-4H
Uwe,
sorry, nothing was seen
or detected here from your transmission today. Not a trace. Der erste Versuch ist meist nicht
genuch (Didi Drahtlos).
Yes I noticed the good
trace on Paul Nicholson's spectrogram http://abelian.org/vlf/fbins.shtml#p=1388246400&b=080&s=sp.
Just look at it the
other way round: You did send a long carrier, only with some short
interruptions. But the gaps were so short that the spectrum didn't notice
them ;-)
More seriously:
Compared to a
continuous carrier, with 50% duty cycle the carrier
component is still there but 6 db down (half average voltage). In terms of
power, on average you are spending 50% of the power. 25% (-6 dB)
goes to the central carrier, and the other 25% into the AM sidebands
carrying the message.
What I
find strange is that the spectrogram trace seems to have
jumped 28 mHz low, once near the beginning and again for an
hour around 14:30. Are you sure that your samplerate correction
had been engaged without interruption?
Best 73,
Markus
(DF6NM)
Sent: Saturday, December 28, 2013 3:05 PM
Subject: Re: Re: LF: Sending Opera with
SpecLab
OK.,
Markus, but the Todmorden grabber shows the signs.its a surprise for me. I
didnt expect it samples such relative short signs. GL Uwe/dj8wx tks
for the correction.
Von: [email protected]Gesendet:
28.12.2013 12:47 An: [email protected]Betreff:
Re: LF: Sending Opera with SpecLab
Uwe,
good news! I'm
watching and searching ;-)
Background noise seems
to be a few dB higher than the last couple of days, but we'll see what's
possible anyway. Unfortunately the OK2BVG grabber
website appears to be down at the moment.
Good luck!
73, Markus
(DF6NM)
PS: In my original
mail, the Op-8 line in the speed table erroneously contained
an entry for Op-4. This has been corrected
beneath.
Sent: Saturday, December 28, 2013 12:14 PM
Subject: LF: Sending Opera with
SpecLab
Hi
all, the PA has been switched on. the next txt block will start
now. GL Uwe/dj8wx
Von: [email protected]Gesendet:
27.12.2013 15:47 An: [email protected]Betreff:
Re: Re: LF: Sending Opera with SpecLab
Hi Markus, Wolf, Stefan, Peter es all, tks for the
advice, Markus
now SpecLab is beaconing in mode Op-4H on 8969.99Hz
the PA is off until it is dry outside.
I keep your proposal txing btwn 0700 and 1400MEZ in mind,
Markus.
GL
Uwe/dj8wx/dj8CAT
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