Differences between 27MHz and 477Mhz

Alistair Mulholland

Introduction

Citizens Band (CB) radio is a popular communication system used by drivers, off-roaders, and boaters to stay connected with each other. There are two main types of CB radio in use in Australia: 27MHz HF (High Frequency) and 477MHz UHF (Ultra High Frequency). In this blog post, we'll explore the differences between these two types of CB radio.

  1. Frequency Range

The most significant difference between 27MHz CB and 477MHz UHF is the frequency range used by each. 27MHz CB operates on the 27 MHz frequency band, which is a low frequency range that can travel longer distances but with lower signal quality. On the other hand, 477MHz UHF operates on the UHF frequency band, which is a higher frequency range that can't travel as far but with better signal quality.

  1. Distance Coverage

The distance coverage of each type of CB radio is also quite different. Due to the longer wavelengths of 27MHz CB signals, they can travel longer distances than 477MHz UHF signals. However, 27MHz CB signals are more susceptible to interference from obstacles, such as hills, buildings, and trees. The shorter wavelength of 477MHz UHF signals means they are less affected by obstacles but have a shorter effective range.

  1. Channel Availability

Another difference between 27MHz CB and 477MHz UHF is the number of channels available for use. 27MHz CB has only 40 channels available for use, while 477MHz UHF has 80 channels available. This means that there is less congestion on 27MHz CB channels, but there are also fewer options available for users.

  1. Equipment Cost

The cost of equipment is another factor to consider when comparing 27MHz CB and 477MHz UHF. Generally, 27MHz CB radios are less expensive than 477MHz UHF radios due to their simpler technology and lower frequency range. However, the cost of antennas for 27MHz CB can be more expensive, as they need to be larger to operate effectively on the lower frequency range.

Conclusion

In conclusion, 27MHz CB and 477MHz UHF have different frequency ranges, distance coverage, channel availability, and equipment costs. 27MHz CB is best for long-distance communication but can be susceptible to interference, while 477MHz UHF provides better signal quality but has a shorter range. The number of available channels is also different, with 27MHz CB having 40 and 477MHz UHF having 80. When deciding which type of CB radio to use, it's important to consider your specific needs and choose the system that best fits those needs.