North America Adventure Frequency: 146.58 MHz

Recently, on the nasota group,  there was a discussion about designating an alternative 2m FM frequency for Summits On The Air (SOTA) use (instead of 146.52 MHz). The main driver for this is that 146.52 MHz can get busy with other radio traffic and/or a busy SOTA activation can tie up the calling frequency for a long time.

Rex KE6MT (SOTA W6 Association Manager) kicked it off with:

A friend of mine, George KJ6VU, has been talking with me and several others about the idea of an FM “Adventure Frequency.”  It would be for more than just SOTA – other *OTA’s could also use it.  There are other ideas to layer on top of it, such as tone signaling so that you don’t have to hear traffic you don’t want to hear, and repeater infrastructure for announcing someone’s on the frequency with a given tone, etc.  But the core thing would be to decide on a frequency and really get it in use.  The National Calling Frequency (146.52) can be great for a few contacts sometimes, but other times it’s problematic either because it’s being hogged or because nobody’s listening.  Of course, this Adventure Frequency could have the same issues present themselves differently, but would alleviate some and pave the path for future additions mentioned above.

I have previously written about the challenges of using 146.52: The Use of 146.52 MHz

One important idea is to include the other “OTAs” in adopting this frequency, most notably Parks On The Air (POTA). Hence the name “Adventure Frequency,” and not “SOTA Frequency.” It is really about hams operating portable in an outdoor setting. Of course, like all amateur spectrum, this frequency must be shared with other users.

It may seem like a simple thing to choose a nationwide simplex frequency but VHF band plans are managed regionally. In particular, there is a mix of 15-kHz and 20-kHz channel spacings. (For more background on this see Simplex Channel Confusion on 2 Meters.)

After some discussion, the group settled on 146.58 MHz. There was some dialog around using CTCSS for signaling but nothing specific surfaced.

Some key points:

  • The NAAF is 146.58 MHz.
  • This frequency is in addition to, not a replacement for, the National Simplex Calling Frequency 146.52 MHz.
  • Local usage will likely vary depending on needs.
  • Program 146.58 MHz as The Other Simplex Frequency in your radio.

What does this mean to you?

Program 146.58 MHz into your radio and have it available. If you are doing SOTA (or POTA) activations, consider using this frequency, especially if you are in an area where 146.52 is used a lot. (I’ve already started using this frequency for SOTA activations near urban areas.)

73 Bob K0NR

The post North America Adventure Frequency: 146.58 MHz appeared first on The KØNR Radio Site.

Bob Witte, KØNR, is a regular contributor to and writes from Colorado, USA. Contact him at [email protected].

5 Responses to “North America Adventure Frequency: 146.58 MHz”

  • Bruce Prior N7RR:

    The 2 m band works best, since its signals penetrate vegetation better than signals, say, on the 70 cm band. Lots of 4X4 hams use the 146.460 MHz frequency, so there tends to be more backcountry activity there. It’s also easy to remember. 73

  • Tony R Everhardt:

    I’ve said from day 1 that using the National Calling Freq for anything else than making calls and moving of was a bad idea. But who am I? Glad to see that another freq is being thought of.

  • KEN N2DF:

    Yes I totally agree with an alternative freq to 146.52 I was planning to attend one of the largest hamfests here in the north east and a ham that I often spoke to but never met face to face suggested that we hook up on ’52 simplex’ I thought that was a bad choice of frequency for several reasons : it would probable be terribly crowded and the hamfest organizers often use that as a ‘call-in frequency’ .52 may be fine for perhaps an initial contact but once that contact is established, a QSY to 146.58 would be more appropriate. KEN N2DF

  • Howard AC4FS:

    Except some areas already use 146.580 for different purposes. Our county uses that frequency for ARES simplex. Having it full of POTA or SOTA (or even IOTA) activators could cause issues when we are doing simplex drills. Then again, nobody “owns” a frequency, neither us, or anybody else, can lay claim to it.

  • Jamie N1XDS:

    Around here where I live (Middle GA) this 146.58 frequency gets used a lot for people to talk local from what I am hearing to talk about anything and everything.

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