Topband: how to set up a Skype receiving beacon
Eric Scace K3NA
eric at k3na.org
Wed Mar 8 09:51:21 EST 2006
The K3NA receiving beacon seems pretty popular. Many
people have written encouragin email (thanks) and the
history file at the station shows connections from all over
Europe, North America, Australia, and Africa.
When I have been working at the station, it's been
interesting to suddenly hear a couple of dashes and a
callsign appear out of the receiver's speaker, and look over
at the computer to see someone listening to my receiver from
This was a very easy project, and I would like to
encourage other topband operators to create a receiving
beacon at their location. Step-by-step instructions are
listed below: 12 steps only!
A receiving beacon doesn't require fantastic antennas or
an exotic location. Many times people want to understand
how their signal sounds at a typical, average topband QTH.
And a receiving beacon doesn't interfere with chasing
DX. When it's time to chase DX, simply grab the receiver
and go work the DX. I usually leave the Skype software
running, so someone who connects to "K3NA160m" at that time
will be listening in to my operating. But you can just
close the Skype application while operating. When you have
finished operating for the moment, just return the receiver
to the beacon frequency, start Skype, and walk away.
-- Eric K3NA
How to create a Skype receiving beacon:
1. Skype configuration:
a. Install Skype on the station computer.
b. Create a Skype username. Perhaps we could agree to
use a common format for beacons of the form "callsign+160m";
e.g., K3NA160m, ON4UN160m, or S9SS160m. (The last two don't
c. Under the Tools menu, click Options.
d. In the Options dialog, select "Sound devices". For
Audio In, choose the soundcard to which you will connect
your receiver. Uncheck the box "Let Skype adjust my sound
device settings". (Skype has an automatic gain control
function and a soundcard level control function. That
second function, designed for human speech in microphones,
appears to distort CW signals and noise from receivers.
Unchecking this box turns off the Skype adjustment of the
e. In the Options dialog, select "Privacy". Selection
the option "Allow calls from anyone". This option allows
people to listen to your receiver without pre-registering as
a member of your Skype contact list.
f. At the very top of the Skype main display, your
beacon user name is displayed. Click on this name to reveal
a gray box that says "Enter a mesasge here for all your
friends to see in their Contact list". Click in this gray
box and provide some description about your beacon. A
"(callsign) 1832.10 kHz (latitude longitude) (antenna
K3NA 1832.10 kHz
41° 34' 45"N 70° 50' 50"W
2. Receiver configuration:
a. Tune to 1832.10 kHz. WA6CDR has suggested using
1812.30 kHz for beacons which could be used by a station
transmitting in the JA window. Both frequencies are
somewhat arbitrary, but located in the two areas of the band
accessible to many topband operators for transmission... and
both frequencies are easy to remember: 18 three two one...
and one two three.
b. Set for CW mode. On my Orion radio I use 1000 Hz
bandwidth so that people can hear nearby band activity, but
you may wish to use something smaller... but still wide
enough for another operator to hit with his transmitter.
Just set the receiver for normal CW reception at your
location (e.g., with a noise blanker if you need it). Be
sure to set the CW pitch to 500 Hz or even higher. Very low
frequencies are not necessarily transported well by Skype,
which is designed to carry human speech.
c. Connect the receiver output to the soundcard
microphone input. Skype only transmits from the mic input
-- and only mono! I use the receiver's line ouput signal
from the back panel -- the line output does not change with
the front panel AF gain control, so there is one less
adjustment to worry about.
3. Soundcard adjustment:
The goal is to set the soundcard mic input level so that
the normal antenna noise on a quiet frequency is just above
the noise floor of the microphone input jack. Skype's
internal AGC will take care of the rest. Too high a setting
results in a great deal of distortion on the Skype
connection. I used this approach:
a. Start a sound display, recording or editting program
that allows you to see the sound levels, relative to the
encoding range of the sound card. I use Goldwave, but there
are lots of options. What you want is a graphical display
of the mic input's signal level vs time. Begin recording or
b. To use the Windows volume control to set the
soundcard level, open the volume control application. On a
WinXP system, this is found on the Start menu under
Choose Options from the menu, and select properties.
The properties dialog will open.
In the Properties dialog, select "Adjust volume for
recording". Now make sure the "Mic" box is checked. Close
the dialog by clicking "OK".
Back in the volume control, make sure the Mute box under
the mic volume control is unchecked. Click the Advanced
button and turn off the mic boost. (If you do not see the
Advanced button, click the Options menu and select "advanced
With the receiver on a quiet frequency, adjust the mic
volume level until the band noise is just visible. When the
mic volume is too low, you will see a flat signal that
represents the floor of the mic input (probably with some DC
bias). The receiver noise needs to be above this level.
4. Finished! Don't forget to tell us that your beacon exists!
-- end --
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