Fall 2006 Issue

FM

2-Meter Band Plans – Many to Choose From

By Bob Witte,* KΨNR

I subscribe to a number of e-mail lists associated with ham radio topics. On one of these lists, a pair of hams was arranging a schedule using FM just below 144.5 MHz. I poked my head in and commented that the ARRL band plan showed this frequency in the “New OSCAR Subband,” 144.30–144.50 MHz. One of the hams replied that according to the Area Repeater Coordination Council (ARCC, the frequency coordination body for eastern Pennsylvania and southern New Jersey) band plan, FM simplex is allowed in the 144.310–144.370 MHz range. Sure enough, that band plan does show FM simplex in this segment of the band.

This caused me to take a look at the various 2-meter band plans around the U.S. Of course, the 2-meter ham band is the most popular VHF band and has a wide range of uses: FM repeaters, FM simplex, weak-signal SSB/CW, propagation beacons, APRS (Automatic Position Reporting System), EME (Earth-Moon-Earth), and AX.25 packet. This makes for an interesting challenge of how to share the frequency spectrum. As we’ll see, how the band is allocated depends on where you are located.

Band Planning

The basic idea of band plans (also called Frequency Utilization Plans) is to coordinate how radio hams use the frequency spectrum. In particular, band plans designate areas for different types of modulation and communication modes, since different modes are often incompatible. For example, an FM signal can’t be received correctly by an SSB receiver, so having those modes operating on the same frequency just creates confusion and frustration. Even if the modulation type is the same, there may still be incompatibility. For example, OSCAR satellites may use modulation types that are the same as terrestrial operating (FM, SSB, CW, packet, etc.). However, terrestrial contacts are incompatible with working the satellites, since it is likely that terrestrial signals would interfere with a satellite without realizing it.

In recent policy decisions, the FCC has been clear that it intends to provide a minimal amount of band planning by regulation and to allow the amateur community to manage frequency sharing. However, there are a few FCC rules that regulate how the 2-meter band is used. The FCC reserves the very low end of the 2-meter band, 144.0–144.1 MHz, for CW emissions only (FCC Part 97.305c). Also, the FCC excludes repeater operation from these frequencies on the 2-meter band: 144.0– 144.5 MHz and 145.5–146.0 MHz (FCC Part 97.205b).

The ARRL Band Plan
In the U.S., the ARRL band plan provides the basic guidance on how the 2-meter band is used.
ARRL Band Plan for 2 Meters (144–148 MHz)
(Source: http://www.arrl.org/FandES/field/regulations/bandplan.html)
144.00–144.05 EME (CW)
144.05–144.10 General CW and weak signals
144.10–144.20 EME and weak-signal SSB
144.200 National calling frequency
144.200–144.275 General SSB operation
144.275–144.300 Propagation beacons
144.30–144.50 New OSCAR subband
144.50–144.60 Linear translator inputs
144.60–144.90 FM repeater inputs
144.90–145.10 Weak-signal and FM simplex (145.01, 03, 05,
07, 09 are widely used for packet)
145.10–145.20 Linear translator outputs
145.20–145.50 FM repeater outputs
145.50–145.80 Miscellaneous and experimental modes

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