Electronics Exhibit

occupying many thousands of square feet. Included is a working model of the ''Oscar" satellite that made communications history. Also National Aeronautical and Space Administration display of our first man-carrying satellite, Friendship Seven.

Other High Interest Ham Events

on the Reservation

Douglas G, Hedm K0OFB

219 Blanchard Blvd.

Syracuse 9t New York causes of television interference (TVI) often are two-man jobs; the amateur sometimes needs help from the owner of the TV set, who obviously can't be of much help unless he knows something about the problem.

In the early days of radio, both amateur and commercial stations often operated on frequencies (dial settings) very close to each other. Because of this, and because we didn't know very much about radio, it was not uncommon for a home-owner to hear amateur stations on his house radio- However, as we learned more and more about electronics, and as newer frequencies came into use, home and amateur equipment was designed so that neither would interfere with the other, provided, of course, that both were constructed and operated properly, But then came television, anil we had to start learning from scratch all over again. We still have a lot to learn!

A radio or television set is like your iiouse. Your house has a front door through which you may invite in or keep out anyone you wish, with just a turn of a key. Similai¥ly, you may invite in or keep out o: your radio or television set any radio signals you wish, with just a turn of the dial- However, just as an intruder may break into your house or sneak in through an unlocked window, unwanted radio signals may find their way into your TV set, whether you invite them in or not, either because the signals are in the wrong place or because the lock on the electronic door is defective.

There are three primary causes of interference to television sets: (£) defective amateur equipment, (2) defective television sets, and (3) freak, unsuspected oddities of nature that occasionally appear (and sometimes disappear« unpredictably. Although each type of interference may look the same to the layman, the different types usually can be identified by an experienced amateur.

When the problem is traced to the amateur transmitter, the amateur merely locates the source of trouble within the transmitter and eliminates it. All amateurs have to take special tests, given by the Federal Communications Commission (FCC), to demonstrate that they know how to operate and maintain radio equipment properly. Once an amateur has


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