Hi Everyone!

Over the past few months there has been a lot of new interest in FM simplex nodes for AllStarLink and EchoLink. These low power devices allow users to connect to remote VoIP nodes and repeater systems using an internet connection and an HT. Most opt to buy or build a device on 70cm.

A couple years ago SBARC expert consultant Matt W6XC identified a few frequencies around 431 MHz that were useful for digital hotspots like the OpenSpot and ZumSpot. But these frequencies are NOT appropriate for analog FM nodes. 

Matt suggests the following options for low power FM usage:

440.000/445.000; 446.860/441.860; 446.880/441.880 may be used as pairs for a low-power duplex node or as separate simplex node frequencies. Please listen to these frequencies with low squelch settings and no CTCSS for a few days before permanently parking your node here to see if and how these frequencies are used. FM simplex nodes are best PL/CTCSS protected, especially if they are left connected to a system like K6TZ or WIN System.

Definitely avoid 446.000 altogether. This is the National Calling Frequency for 70cm. 446.500 and 446.520 are "General Simplex” frequencies. Others many want to use these for simplex QSOs or other itinerant purposes so please don’t park your node on any of these three frequencies. 

440 is tough given the lack of simplex allocations. It's a truly stuffed band!

If you are interested in these FM VoIP nodes, consider the ClearNode and SHARI projects.