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Hi Stefan, thank you for this extraordinary
report! This is really fun, even though the Hell stuff may still involve a bit
of gXXXXwork ;-)
But beware you've been caught speeding...
There is clearly a 60 mHz Doppler variation in the
screenshot, implying a change in radial velocity of 132 m/s. So you must
have been doing at least 238 km/h ;-))
Next we'll have
Dave 'YXM show us how to get the transmitter into the
other car
and strive towards a truely
mobile-to-mobile LF contact.
Best 73,
Markus (DF6NM)
Sent: Monday, January 17, 2011 12:21 AM
Subject: LF: DF6NM copied from the highway...
LF,
I've been on a
tour in Freiburg over the weekend and just back home. It
was possible to
check my modified GSM external car antenna (with a
magnet foot), modified as
an active antenna for 137 kHz. The RX is my
homemade receiver (12V/50mA,
SBL-3, 125 kHz downconverting). Between RX
and antenna is about 4m RG174.
Signals were monitored on my netbook
using SpecLab. The soundcard drift is
compensated by locking on DLF (153
kHz) which worked very well. I've used no
external GPS module so the
etal wasn't in a PLL, never mind.
I've
been watching the QRSS-3 and QRSS-60 active region while beeing on
the
highway A5, see:
http://maps.google.de/maps?f=d&source=s_d&saddr=heidelberg&daddr=freiburg&hl=de&geocode=FSzQ8QIdXXOEACnN3MwOBcGXRzHXOiREAOrm7w%3BFQJh3AIdx9Z3ACll1gtWJhuRRzGwV9-lt2sfBA&mra=ls&sll=47.997186,7.853767&sspn=0.145654,0.438766&g=freiburg&ie=UTF8&ll=48.821333,7.910156&spn=4.585752,14.040527&z=6
This
was the first test with the /m LF antenna and there seems to be a
lack of
sensitivity of about 20 dB. The LF noise is just a few dB above
the
soundcards noise, DCF39 appeared at 45 dB on 2.8 Hz. There was
almost no
local noise from the car, just some 420 kV lines near the
highway caused QRM
when driving under or near them.
Although there is a lack of sensitivity,
it was anyway possible to copy
DF6NM in QRSS-60 and in HELL (480 mHz FFT,
traces visible) during
driving. See the attached pictures. Copy of "NM" was
near Karlsruhe,
about 200 km distance.
I hope to improve the SNR /
sensitivity now and will be able to copy him
and others in CW to try a /m
xband QSO...
73, Stefan/DK7FC
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