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Getting your feet wet in the World of International Radio and Shortwave!

I thought it fitting to begin my series on the basics of World Band radio with a review of a radio that I have been playing with for some time - The Grundig Traveler G3, one of the latest offerings of Grundig Eton.

The Grundig Traveler G3 features world-band radio coverage from 150khz to 30Mhz, aircraft band 118 to 137Mhz and standard FM stereo...

Photo Right: The Grundig Traveler G3 is a state of the art World band radio - just the thing to get you into the radio listening game! This sample provided by Durham Radio of Ontario Canada.

"Whoa Colin! Coverage from what to what? Mhz? Khz? Aircraft? Isn't this chapter about the basics?"

Right. Sorry about that. From the start then...

Most people are familiar with standard AM and FM radios, yea? Truth be told, these numbers might actually be on the decline as the tide of new technology washes over society.
Nonetheless, here are some intro snippets of information for those totally in the dark about the fundamentals of radio reception:

• AM radio operates on frequencies between 530khz and 1700khz. 1khz is 1000 cycles per second. And through the miracle of early 20th century technology, radio frequencies much above a dozen khz or so can readily have audio intelligence embedded or modulated onto the primary radio frequency.
• Channels on the AM (or medium-wave) radio dial are separated by 10khz in North America and 9khz in the rest of the World. This separation allows for enough room to add intelligence to the signal. It is no coincidence that speech and most music only goes up to around 10khz, so it's win-win. A good example would be a radio station on 540khz. The carrier (by itself) is centered on 540 khz and audio intelligence (when modulated on this frequency) extends in 2 directions away from the center "carrier" - these are sidebands. By design, there are 2 of them. They are identical but opposite in some neat ways - we will not discuss why here - at least not right now.
• AM signals during the day are limited to around 50 to 75 miles - dependent of course on the power of the transmitter. Transmit power in North America is limited to 50kw but some radio stations operate successfully with as little as 250 watts.
• At night time, AM signals can travel thousands of miles depending upon conditions in a section of the upper atmosphere known as the ionosphere. Since this ionized layer is constantly changing, AM radio listening at night time can be a wildly variable and entertaining experience. Like the proverbial box of chocolates, every time you turn the radio on it is a different scenario. That said, stations with enough power and a suitable location and frequency can command large distances and audiences quite reliably.
• If you are lucky enough to live in coastal areas of North America, you are probably picking up transoceanic signals and don't even know it!
• Unlike the Internet (and streaming broadcast media), one radio signal from one radio station can have an unlimited number of listeners at any given moment. A 50,000 watt transmitter can easily reach millions of listeners with no variation in the "overhead" or basic operation of the station. To have 1 million listeners streaming an Internet connection to a live audio feed from a radio station is, for all intents and purposes, completely impractical and almost entirely unfeasible. Read - impossible.

"Transoceanic radio reception in North America?! Is that possible?"

It sure is - and you might not even notice that these signals are there because you are not expecting them. Most people do not expect to hear foreign languages or extremely distant stations on their AM radios... so they kind of "tune" it out - if only on a psychological basis. We will talk more about this transoceanic stuff later.

So knowing that AM radio spans a small range around 1Mhz (1000khz), what happens above that frequency? Good question. By international definition, medium wave extends up to 3Mhz - beyond that is an area we call "HF" (High Frequency) or shortwave (SW). Well, we know that AM stations can skip for a couple of thousand miles at night time - now apart from being able to hear a distant baseball game or a farm report from Kansas, it would not seem to be a practical medium for mass communications. On the contrary, many channels on the AM dial are designated as "Clear channels" (within certain limits of course...) Back in the 1st half of the 20th Century, some clear channels on the dial were set up to have coast to coast coverage - that is, a station in New York city could be easily heard in Los Angeles, California... and vice versa. Not so much anymore. A modern example is KGO 810khz in San Francisco which enjoys coverage from Mexico to the Gulf of Alaska on one 50,000 Watt transmitter. Pretty impressive indeed and the potential audience is in the millions.

Photo at right: The little Sony SRF-59 was the pocket sized portable that spawned a renaissance in the wireless world - Called ULR or ultralight radio listening, this < $30 marvel brought long distance radio station chasing to every ones budget.

So, the shortwave spectrum improves on this medium by taking advantage of some of the properties of the ionosphere at higher frequencies - and one of those properties is "multiple skip" combined with the fact that higher frequencies pass through layers in the ionosphere that block the lower frequency AM radio and allow long distance reception during the daylight hours! How cool is that? Sure, there is a lot of radio listening to be done at night time on the short wave radio dial but shortwave is alive and live 24 hours a day generally.

"Let me get this straight. There are parts of the ionosphere that reflect some signals some of the time but not all of the time and frequencies that only get reflected above a certain frequency at certain times of the day? Did I get that right?"

Yes, you did! In a nutshell, the whole reason there is long distance radio reception is the fact that the exists an ionosphere (that has several layers) and the fact that radio signals also bounce of solid ground and ocean. If not for these things, radio would be *ahem* nowhere baby!

Lesson one - Let's get some! Virtually any radio (with an AM dial) has the potential for radio fun. So find one. Every household should have a standard AM-FM battery powered radio if only for the purposes of receiving news in the event of a domestic emergency - like an earthquake, tidal wave, tornado or plague of frogs. Seriously, it is an integral component in any first aid or emergency kit. And if you do nothing else beyond these first few pages, I beg of you: Get a radio that is powered by a battery and put it aside for a rainy day... or worse.

"OK, ok, I have the radio... now what?"

1. If you are an apartment or condo dweller, get yourself to a window - not so important if your home is wood frame construction. Covered balcony - nice weather, even better. It should be dawn, dusk or early evening.
2. Switch on your radio and select the AM Band. If it is analog (traditional tuning dial) head to the bottom of the dial (530khz) and start tuning up.
3. You may hear a pile of noise - in which case find a better location. Electrical and electronic noises sources coming from near your residence or within your residence can effectively preclude reception on any radio frequency. Common sources of radio interference include fluorescent lights, light dimmers, exercise bicycles, fish tank heaters, power-line Internet adapters and a myriad of other irritants. In order for you to hear radio and exploit distant reception, you need to be in a fairly noise free environment. Such a thing is achievable so do not get discouraged.
4. If noise from (3) is not a problem, proceed to tune of the dial and get familiar with the radio signals in your area. Some may be local. Some may be in the next state or province. Some signals might be originating from half a continent away.

 "So... where are these signals coming from? How do I find out?"

Chapter 3 - or tuck tail and return to chapter one -