ARRL Technician Practice Exam

What is a common repeater frequency offset in the 70 cm band?

1. Plus or minus 2 MHz

2. Plus or minus 5 MHz

3. Plus or minus 10 MHz

4. Plus or minus 12 MHz

The correct answer is: Plus or minus 5 MHz

In the 70 cm amateur radio band (430 to 440 MHz), a common frequency offset for repeaters is plus or minus 5 MHz. This offset is established to prevent interference between the output and input of the repeater, ensuring that they operate smoothly. The selection of a 5 MHz offset allows for effective communication while maintaining a clear distinction between different channels, which is particularly important in the crowded VHF/UHF bands. The other options represent offsets not commonly used for the 70 cm band. For example, a 2 MHz offset would be more suited for certain VHF bands, while 10 MHz and 12 MHz offsets are significantly larger than typical for the UHF band. Stick with the established 5 MHz offset for repeaters in the 70 cm band, as it is widely recognized and implemented within the amateur radio community.