Using Radio Equipment

Care of Transceivers

Some Radio equipment are manufactured for uses in harsh environmental conditions. However, transceivers should always be protected from rain and spray dirt dust extrema heat and cold, By being positioned inside a car or building. They should be fine most of the time but hand held are very susceptible to damage if you suspect that your transceiver my be exposed to harsh environments take steps to minimise the risk to the equipment like keeping it in a sealed plastic when on the water or dusty environments only removing it when required and such. In a car they should be securely fastened to the prevent damage to them and you on bumpy roads. After use, a microphone associated with a transceiver should always be replaced in its holder or bracket. For a variety of reasons, one of which is that it can result in the transmitter being activated through inadvertent pressure on the microphone press-to-talk switch and without the knowledge of the operator. As a consequence, all background noises, including conversations made in the vicinity of the transceiver, are transmitted. Use of the frequency by other nearby stations cannot take place until the station responsible has been located and the problem corrected. It is normal practice to locate fuses in the leads connecting the transceiver to the battery supplying the power. The purpose of these fuses is to "blow" should the transceiver malfunction and start to draw a current in excess of the fuse rating. By doing this, the fuses protect the wiring system from serious damage and the possibility of fire.

Common Radio Controls


This may be a push button rocker switch, or a rotary switch. It will usually be marked ‘Power’, ’PWR’, or ‘ON/OFF’, and is often part of the volume control

AF Volume:

The AF volume control or Volume, control adjusts the loudness of the received signal. This control is often labelled ‘Vol’; AF gain _ which means audio frequency amplification and it works on that part of the circuit that amplifies audio frequencies

Squelch or Mute:

The squelch or mute control silences background noise in the absence of incoming signal. You normally set the squelch control to just eliminate background noise when no signal is present

Setting the squelch to high could cause weak signals to be missed, so the level is usually set to “just cut off the noise”. It is recommended to listen and ensure that channel is not in use before transmitting. This may require, particularly on 27Mhz radios ‘Opening the squelch’ to check for the presence of very weak signals before transmitting

RF Gain:

The RF gain control is a little like the AF Volume control in that it will adjust the volume of the received signal. The difference is that where the volume control adjusts the amplification of the receiver in the audio frequency circuitry, the RF gain control adjusts the amplification in the radio frequency circuitry, the RF gain controls the ‘sensitivity’ of the receiver, which is the measure of the ability of a receive to detect weak signals

Channel selector:

The channel selector is ever a set of up and down buttons or a large knob. By using the buttons or knob you can select every channel the radio is able to use


This control allows you to make small adjustments to your receive frequency in order to make a received SSB signal sound more natural and properly tuned-in, without changing the transmitter frequency.

Microphone Gain:

This control adjusts the audio (speech) Level out of the Microphone amplifier. On SSB this control determines the Max transmitted power, setting the microphone gain too high will cause your signal to be distorted and you will cause interference to other stations operating near your channel


Receiving or RX is one of the more important aspects of radio oppression.

Setting the Squelch

Turn the unit ON

Adjust volume or AF gain to a comfortable level.

Note: You must select a channel which is not in use before setting the SQUELCH control on your radio.

Think of the Squelch control as a gate. If you turn SQUELCH fully on it raises the "Squelch Gate" so high that no signals get through.

If you turn the SQUELCH fully off it lowers the "Squelch Gate" so that everything gets through - noise, weak signals, and strong signals.

To set the "Squelch Gate" to the desired level, turn SQUELCH Control Until you hear noise. Then turn the SQUELCH Back just until the noise stops. Now only strong signals get through.

RF Gain

Normal this control is turned right up so you can hear every thing around, if noise becomes a problem and the Squelch will not take it out reduce the RF gain. When receiving signals set the RF gain so that almost all of the background noise very low or no existent.


Some times you the signal you hear will sound like aliens talking, being high pinched or very low this shows that they are a little off frequency, to correct this turn the Clarifier left and right until the voice sounds normal


Transmitting is normal activated by means of a PTT or push to talk Switch on some radio there is a control called Microphone Gain this amplifies the signal out of the microphone so that someone with a soft voice can be Herd and Someone with a loud voice can be turned down. Most of the time transmitting requires very little work just press the microphone and go but do not transmit to long, some radio have talk timers that will stop the transmission if it is left on to long, also repeated and pronged conversations drain batteries and make the radio very hot in some cases so hot you can not touch it. It is also important to remember to listen before you transmit so as not to talk over Someone else

The Microphone

All radios that are capable of transmitting will have a microphone of sum type most radio microphones are as below pictured.

All radio Microphones have a PTT or Push to Talk button pressing this button you enable the transmitter of the radio. It is always good to leave a second before talking as to allow the radio to power up. If you leave the gaps between pressing the button and talking to short you can cut off your voice. It is not necessary to eat the microphone or yell into it the microphones on modern radios are quiet sensitive and yelling into them only distorts your signal making it harder to under stand you. Like wise eating the microphone will muffle your voice the best placement is 2 to 3 cm from your mouth directly in front of your mouth. The same is said for hand held's, hold the radio or extension microphone 2 to 3 cm from your mouth. Always let go of the PTT 1 second after you are finished so as to not cut of the end of your signal, it is important to leave a 3 to 4 second gap from when the station you are talking to finishes there over and when you start yours, this will allow breakers to get a chance to get a word in.

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