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| How To Get Started As A Radio Hobbyist Without Really Trying |
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AM broadcast radio - some say it's dying, some say it's been dead for years - since radio manufacturers started putting the FM broadcast band on receivers too. Certainly, the format of your basic, garden variety AM broadcast station circa 2003 is a lot different from what it used to be decades ago when AM was in its heyday. For the most part, the days of multiple top-40 AM stations serving a listening area are gone - that stuff's all moved to FM, where there is less noise and music just sounds better (unless you live near Buffalo, where upon landing at Buffalo/Niagara International and setting your watch back the obligatory twenty years considering where you've just arrived, you can tune to 1520 WWKB and hear the same music, and many of the same DJ's, you would have heard here back in the 1960's). But, is the band dead? Far from it. Tune across the AM band some night and see for yourself. Yes, you'll hear noise, and yes, if there's a thunderstorm anywhere nearby you'll know about it in short order, but you'll also notice there are a lot of stations, strong ones, weak ones...ones that weren't there at two in the afternoon. Where did all these other, far-away stations come from? Why couldn't I hear them this afternoon? A crash course on radio wave propagation would take up the rest of this page and leave me no room for talking about DX'ing the AM broadcast band, but the short version is that it has to do with something called "D-Layer absorption" and that is a phenomenon which disappears shortly after sunset, allowing those far-away stations' signals (which were there all along, you just couldn't hear them because their path from the transmitter to your receiver was being blocked by highly ionized particles in the D layer of the atmosphere that the sun's rays got all worked up into a tither) to reach your radio's antenna, where your radio converts the signals into something your ears can (hopefully) recognize as a radio station from "way out yonder". This isn't necessarily a good thing, of course. The people who live in the faraway places where the station you're hearing is located might enjoy listening to some really awful stuff...like the stuff the kids down the street listen to when they drive by your house at 3:00 AM and rattle your windows. However, while you're waiting for the kids to get deaf as a stump from constant self-inflicted exposure to all that bass-thumping noise they seem to think qualifies as music (and they WILL eventually...buy stock in a hearing aid company now before all these kids turn 30!), consider that if you're a cable-TV-challenged baseball or football or hockey fan, you're in luck, because AM radio has become the domain of live radio play-by-play and countless sports talk shows...just spin the dial for your nightly sports "fix" and try not to run up the phone bill by calling the local numbers instead of the toll free ones when you want to get on the show and chip in your $0.02 worth. Of course, if all you want to do is log, and maybe QSL, as many faraway AM stations as you can, you're in luck. All you really have to do is tune in at the top of the hour and listen carefully for the FCC-required station identification, thus sparing yourself the poor attempts at melodic composition and endless calls from drunken sports fanatics who are sure their team will win the World Series /Super Bowl/Stanley Cup this year. Just grab the station callsign, swing by a website or two to help you ID the station from the callsign, and you've logged another one that you can also QSL if you wish. The easiest AM broadcast stations to log are the 50,000-watt powerhouse stations operating on what once were clear-channel frequencies (the aforementioned WWKB 1520 in Buffalo is a good example). Many AM stations reduce power and/or switch to a directional antenna array at night to minimize interference with other stations, and some stations don't run much in the way of power to begin with, so there are also tough catches to go along with the easy ones for those who want a bit more of a challenge. If you're one who looks for content along with the catch, there is still quite a variety of talk shows on various subjects as well as news, music (even the real McCoy!), sports, and other programming to enjoy while waiting for the all-important station ID. A good idea if you want to DX the AM band is to sit down during the afternoon and tune from one end of the band to the other noting what local stations you can hear. That way, you'll know when you sit down at night and tune in a station from far away, because it won't be on the list you made earlier. "Hmmmm......there was no station at 1520 this afternoon, maybe this is that WWKB that John was talking about!" (Entirely possible if you're anywhere in the eastern U.S. but not as likely if you're on the left coast somewhere) As is the case with other radio listening activities, I recommend you keep a log. Your logbook becomes a better resource every time you make an entry in it. In time, your own log will become your number one piece of reference material! The tips on keeping a log that appear on my shortwave broadcast listening page also apply to other radio activities. Write down those callsigns, frequencies, programming notes and other pertinent info, and then five years from now if you've forgotten it, you can go back and look it up. Fail to write it down, and you'll eventually wish you'd listened to me and taken copious notes on your listening activities. Take my word on this and keep a logbook! Other than that, DX'ing the AM band is perhaps a little easier than playing on the shortwave bands for a couple of reasons. For one thing, all the stations are in the same mode - you stick your receiver in the AM mode and leave it there - and all U.S. stations are in 10 kilohertz steps, so you know exactly where the carrier frequency is. Furthermore, there's only one band, and it's loaded with signals, so there aren't a lot of controls you need to play with a lot...it's basically "See the knob on the front of the radio? The big one? Turn it!" It doesn't get any easier than that. Even a child can do it, as many a child has proven - including me, back in the days when it was still possible to measure my age in single digits. Finally, just about any radio, even a cheap, no frills/bells/whistles, AM-only clock radio will produce at least some results, so you can enjoy this facet of the hobby with a really minimal investment to get started. You can even use the radio in your car. Just tune around and see what you can find...that's what it's all about. Enjoy! |
| Tips On Tuning |
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If you're going to DX the AM broadcast band it helps to bear in mind that while all U.S. stations are spaced in 10 kilohertz steps, the ones over in Europe are spaced 9 khz apart. Better quality receivers allow you to select between 9 and 10 khz step sizes for this reason (my DX-394 has this feature, for example). Another thing that helps is to take advantage of ALL the tools your radio offers you...some of which may not be obvious. For example, many of today's AM/FM portables have the obvious telescoping whip antenna which most users extend, turn the radio on, and spend (read: waste!) a lot of time moving the whip around trying to get a better signal from an AM station. What makes this a waste is that the telescoping whip is generally for FM only. Inside the radio's case you'll find what's called a ferrite rod antenna, so named because it consists of a ferrite rod (imagine that!) with one or more coils wound around it. This is the antenna these radios use for AM reception - so you can fiddle with the FM telescoping whip until you're blue in the face and it won't make any difference to your AM reception. One advantage that ferrite rod antennas have is that they are directional - which means that by physically turning the radio, you can often get better reception of the station you're trying to hear OR reduce (null) the signal of an interference source such as locally produced noise or another station on the same or a nearby frequency. Many listeners overlook this tool and its potential - especially beginners - but many diehard AM BCB DX fans have fashioned a swivel base for their radio so they can turn it more easily to peak a desired signal or to null an interfering signal. If you're a cheapskate like me, a "lazy susan" sold in the housewares section of most discount department stores makes a good swivel base for a portable radio. These are sold for putting on your kitchen table and putting the salt and pepper shakers, sugar bowl and creamer, napkin holder, and other such stuff on the "lazy susan" which you can then turn to bring all that stuff within easy reach. However, you can just as easily place your radio on one of these and use it to easily turn the radio so as to orient the ferrite rod antenna inside of it for best reception. It's also worth noting that, although the 10 khz (or 9 khz for Europe) step size tells you exactly where the center frequency of a station's carrier is going to be, center channel is not always the optimum tuning frequency. Try tuning off 1 or 2 khz once in awhile and see if it helps - you'll be surprised how often it does. Finally, in addition to all the broadcast stations up and down the band, you'll sometimes run across what are generally called TIS stations. TIS stands for Traveller Information Stations, and most of them are relatively low-powered stations operated for the purpose of broadcasting tourist information, traffic advisories, weather bulletins, and other such fare. Here in my area, the New York State Thruway Authority operates WPAN-997, a TIS, located on 1610 khz. These stations' signals, though low-powered, are subject to propagation just like any other signal. I've sat here in Tonawanda, NY and logged a TIS station down in Florida late at night. Because of their low power, TIS stations are much harder to DX than regular broadcasters, but if you're looking for a challenge, they might be just what the doctor ordered. You can search for TIS stations on the Internet by pointing your web browser to the following link: |
| http://www.fcc.gov/mb/audio/bickel/tis.html |
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| The photo at the top of the page shows a GE Superradio, a popular portable receiver for AM broadcast band DX'ing. While most any AM receiver will yield some results (even an el-cheapo AM clock radio!), better models such as the one above will include some features desirable to serious hobbyists. |