■ FIGURE 6. The PC screen display for the SDR-IQ
is derived from the SpectraVue Software and shows
frequency on the horizontal scale and signal
amplitude in dBm. The waterfall display is optional.
239 UHF coax connector and an MFJ 16010 antenna
tuner ( www.mfjenterprises.com). The tuner consists of
an L-network with switchable inductor and tunable
capacitor. It lets you match the high impedance of a
wire antenna to a 50 ohm input on the radio. Adjusting
the tuner lets you optimize signal strength on the
frequency you are receiving.
If you do not have a good antenna, you may be
disappointed at your results which may cause you to
give up before you really get to experience the true
pleasure of SWLing. If you are going to invest in a
radio, spend the few extra bucks to get a great
HOW TO LISTEN
Night time is the best time for listening. The bands are
quieter and the signals travel farther. From my house in
the hill country of Texas, I can hear both coasts easily and
almost anywhere in the US. Start listening to the 49 meter
band around 5. 9 MHz and tune up from there. Another
good spot is the 31 meter band in the 9. 5 MHz range.
There are lots of international broadcasts there. The 20
meter ham band in the 14 to 14. 3 MHz range is also
fertile territory. You will need to use your BFO to hear the
CW and SSB voice signals.
Shortwave is AM, so is very susceptible to noise
interference. Noise is random amplitude variations. It can
come from lightning and other atmospheric effects but
most of it is man-made. Auto ignition noise is one source.
Fluorescent lights and the new compact fluorescents
(CFLs) are horrible offenders. Turn them all off before
tuning in. If you are still getting lots of noise, it could be
some other appliance. Turn off anything that creates
interference. If it has one, use the noise blanker on your
Remember to be patient. You will usually need to
listen for a while before the station identifies itself and
its location. On the AM band, you may only get the
call letters, but just keep listening until you can figure
out where the station is located. Lots of SWLers keep a
For more in-depth coverage of the SWLing hobby, try
these targeted magazines.
Passport to World Band Radio
log recording the time, date, frequency, call letters,
and location. Some stations will even QSL. This is
where you send a report of reception and signal strength
along with the time and date to the particular station.
They, in turn, send you a QSL card which is a post card
usually with the station call and location acknowledging
SWL can be fun and addictive. Who knows, maybe
you’ll soon want a ham license so you can talk as well as
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