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Oct 11, 2014

PSK-63 to Argentina

PSK-63 to Argentina is a long way from Toronto. Conditions were right though, so here's the proof for the contact.

Oct 9, 2014

DXing and DXpeditions

Oct 5, 2014

QSL From YL3FW

A new country for me today - Latvia!
That brings me up to 117 countries, all with 100 watts or less.

eQSL From YL3FW



Oct 4, 2014

My current Reach

Did some PSK and WSPR today as the bands seem to be open.  Still using my Magloop from MFJ hanging in a tree. It's up about 20 feet now.



Oct 3, 2014

The Icom IC R75 Shortwave Receiver


New Ham Shack!

Sep 28, 2014

10 Meters open to Europe





Sep 3, 2014

YV4NN



QSL Card From YV4NN

US0LW



QSL Card From US0LW

Jul 23, 2014

What is a Balun?

The word balun is a combination of the words BALanced and UNbalanced. As the name hints, it’s a device that connects a balanced system to an unbalanced one. Some examples can be seen here.

Baluns are often used to connect a balanced antenna (like the half-wave dipole) to an un-balanced feedline (like the coax). The balun, among other things, helps prevent current flowing on the outside of the coax. Otherwise, when this current (called common-mode current) appears on the outside of the shield, the feedline behaves as if it were an antenna. There are several reasons why this isn’t what we want to have happen. If the feedline is behaving like an antenna, and it passes near a phone line on the way inside, you will probably interfere with the telephone. Since antennas work both ways, if the feedline comes close to a noisy power line, chances are it’ll pick up the noise and bring it inside to the receiver.

That’s not to say antennas won’t work without a balun. Quite the contrary, but it generally will be true you’ll have fewer problems with noise and interference if you take steps to avoid current on the outside of the feedline.

Some baluns have the ability to transform to a higher or lower impedance. This has to do with the ratio of turns contained in the windings of the balun. You’ll see baluns called 1:1 or 4:1, etc. This is the ratio of impedances the balun is intended to connect. For instance, if one wanted to connect a 450-ohm balanced feedline to a 50-ohm unbalanced line, he would select a 9:1 balun. You will learn later this is a convenient way (for instance) to bring a balanced open wire line from a multi-band antenna into the house, using a short length of coax.

In our case however, since the center of a half-wave dipole is closer to 50 ohms impedance than it is to most other standard feedlines, and since we are using 50 ohm coax, we need to have a 1:1 balun