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Hand Held Transceivers. ARRL Book Section 3.4. The HT. Some people call them walkie talkies Most amateur radio operators consider that a word for a toy Can also be called Hand Held Transceiver, Hand Transceiver, or HT (anyone want to guess what HT stands for?). Warnings.
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Hand Held Transceivers ARRL Book Section 3.4
The HT • Some people call them walkie talkies • Most amateur radio operators consider that a word for a toy • Can also be called Hand Held Transceiver, Hand Transceiver, or HT (anyone want to guess what HT stands for?)
Warnings • People may think HT is a great mobile first choice – its not • We are very spread out, power of an HT will really limit you • An HT has 2.5 to 7 watts of power, a mobile has 25 to 75 watts • HTs are generally limited to battery packs that last only a few hours – they don’t have the staying power for a long emergency operation • People may buy used equipment – HTs have often been handled rough and have much higher risk of being bad. • Chris said mobile first for a reason
More Limitations • HTs marketers try to put out cheap packages – antenna is a short cut area – a crumby antenna is a great way to waste power • Short stuby antenna on an HT is called a rubber duck • A Rubber Duck Antenna does not transmit a signal as efficiently as a full sized antenna (T9A04) • One Way to get a stronger signal from a hand held is to use an external antenna (T7A03) • Most radios have plug at top called a BNC connection • Can get a full size antenna with a BNC connection or a BNC connection adaptor • There are a few HTs that have SMA plug connections
Polarization Perils • Mentioned that radio waves in fact have a magnetic wave and an electrical wave • Which one faces up is very important • Most mobiles and repeaters using FM are vertically polarized – ie antenna faces straight up and down. • (most side band work is horizontally polarized) • If one antenna is vertical and the other is horizontal the signal between them can be 100 times weaker (T9B08) • Problem for Handheld – it is easy to tip the antenna off vertical • When trying to reach a distant repeater keep the antenna as near vertical as possible (T9B07)