There are several popular meter bands that can be used on handheld transceivers, and the 70 cm band (between 420 to 450 MHz) is one of the most popular ham bands used for repeater and simplex operations.
Let’s take a look at the frequencies that can be used on 70 centimeters.
Federal Communications Commission
First and foremost, you need to understand the frequency authorizations that are granted by the Federal Communications Commission (FCC) for your specific license class. Similar to the 2 meter band, technicians and licensees in a higher class are granted privileges across the whole 70 cm band, which ranges from 420 to 450 MHz. The 70 cm band is a really large one. Compared to the 4 MHz spectrum offers on the 2 meter band, the 70 cm band provides 30 MHz, which is quite a significant difference.
The rules set forth by the FCC don’t indicate any particular restrictions for mode on the 70 cm band; however, there is a restriction on operating below 430 MHz when you’re near the borders of the United States and Canada, which is referred to as the Line A restriction. If you plan to operation on this part of the band, you can check part 97 of the FCC regulations.
The Band Plans
Knowing the frequency authorization from the FCC is a good place to start; however, you do need to explore a bit more. Operators of amateur radios utilize several modulation techniques in order to communicate. Typically, the modulation techniques aren’t compatible, as one type of signal cannot be received by a radio that is set on another type of modulation.
For instance, an FM receiver cannot be received on an SBB signal, as well as the other way around. Amateur Television (ATCV) is one of the most interesting modes that can be used on the 70 cm band. Generally, these signals are 6 MHz wide, so it would stand to reason that you should only use a wide amateur band, such as 70 cm.
You do have to use the FCC authorized frequencies wisely, and you can do so by sharing the band with others in order to avoid unnecessary interference. As such, it would make sense to have a band plan that splits the band up into segments for the different types of operation.
The 70 CM Band Plan
A variety of radio operations are supported on the ARRL 70 cm amateur band plan. Large segments of the band are reserved for FM operation, so it’s no wonder FM mode is so popular. There are segments of the band that are dedicated for both repeater inputs and outputs. On the 70 cm band, this standard repeater offset that is used is 5 MHz. Some regions use +5 MHz offset, while in other locations, -5 MHz are used. In any location, the offset would typically be the same on all repeaters. As such, in some locations, you’ll need to dial in the repeater output frequency between the 442 MHz and 445 MHz range and choose +5 MHz offset.