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by disinfoniacs #69 & #1




in depth

In ham radio, setting the transmit and receive frequency is a crucial step in operating your station. The method of entering the operating frequency on a modern transceiver can vary, depending on the model of radio being used. Some radios allow you to enter the frequency using the keypad, while others have a VFO (Variable Frequency Oscillator) knob that can be turned to set the frequency.

To facilitate quick access to frequently used frequencies, many modern ham radio transceivers have a memory channel function. This allows you to store a favorite frequency in a memory channel, allowing you to recall it quickly with the push of a button.

FM transceivers often include a scanning function, which is a convenient way to automatically find active frequencies and make new contacts. The scanning function tunes through a range of frequencies to check for activity, making it easy to find a frequency that is in use.

Squelch control is a useful tool for eliminating static on the receiver of a ham radio. It functions by muting the receiver output noise when no signal is being received. By rotating the squelch control, you can adjust its sensitivity, allowing you to hear only very strong stations or weak-signal stations. If you open the s quelch all the way, you will hear full static or "hiss," allowing you to receive weak signals. By rotating the squelch control in the opposite direction, you will only hear very strong stations.

Having multiple receive bandwidth choices on a multimode transceiver is a useful feature that allows you to optimize your radio performance based on the mode you are using. Some radios permit you to change the filter to match the mode you are using, such as Morse code, SSB voice, or others.

Having multiple receive bandwidth choices on a multimode transceiver enables you to reduce noise or interference by selecting a bandwidth that matches the mode you are using. In addition, you can further improve noisy signals by using a bandwidth filter, which limits the signal bandwidth that you hear.

For example, to eliminate noise and interference during SSB (Single Sideband) reception, it is recommended to choose a 2400 Hz bandwidth filter. The right filter depends on the mode you are using.

When operating using FT8, the audio input and output of the transceiver must be connected to the audio input and output of a computer running WSJT-X software. This allows for the exchange of data between the transceiver and the software, allowing for efficient and effective communication.

When operating using CW (Continuous Wave), many ham radio operators choose a 500 Hz bandwidth filter. This is because CW, or Morse code, uses a very low bandwidth, only sending a single tone, unlike voice, which has a wide range of tones. To match the narrow bandwidth of CW, you would select a narrow filter. This can help to reduce noise and improve the clarity of the signal.

It's crucial to tune in to the right frequency that the other station is transmitting on. There are certain tools to help with this, which can enhance the overall quality of the communication.

For instance, in the case of FM reception, if you tune the receiver above or below the signal frequency, you will experience a distortion in the signal's audio. This can result in an unclear communication and should be avoided.

In modes such as Single Sideband (SSB) or CW, the Receiver Incremental Tuning (RIT) function comes in handy. The RIT enables you to adjust the receive frequency independently of the transmit frequency. If the voice pitch of a single-sideband signal seems too high or low, the receiver RIT or clarifier can be utilized to change the receiver's frequency and resolve the issue.

In addition to proper tuning, sending good audio quality is crucial to ensure other stations can hear you better. If you are using SSB and are informed that your transmitted audio is distorted, it's often caused by excessive microphone gain. In such cases, reducing the microphone gain can help rectify the problem and improve the overall audio quality of the transmission.

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