[aprssig] The 30m Band Utilization Chart -- 2 June 2011

Ian Wade G3NRW g3nrw at yahoo.co.uk
Thu Jun 2 02:58:45 EDT 2011

Just in time for the 30m Multi Mode weekend -- 4/5 June 2011.

A few weeks ago Don Hobson, KB9UMT, founder of the 30m Digital Group, 
published the updated "unofficial 30m bandplan" on the 30MDG reflector. 
I responded, saying that the listing was a little misleading, because 
some frequencies were dial frequencies, others were emitted frequencies, 
and it wasn't clear which was which.

Don challenged me to do better. At first I tried to improve the listing 
format, to draw the distinction between dial and emitted frequencies, 
but quickly realized this was not an easy task! I finally capitulated 
and decided on a graphical format instead:


I have called it a "Band Utilization" chart. It is exactly that. It is 
not a "bandplan", nor even an "unofficial bandplan". Rather, it is an 
attempt to graphically portray the many modes that are actually in use 
on 30m today. On the chart there is a clear distinction between dial 
frequencies and emitted frequencies, helping you to accurately set the 
correct frequency and to identify signals as they appear on the 

Prior to posting the chart on my website, I sent a couple of draft 
versions to a number of the world's "movers and shakers" in digital 
communication and HF. Several of them responded with very helpful 
comments, suggestions and corrections, for which I am very grateful.

It's been an "interesting" exercise to fit everything in, but I hope you 
will find the finished chart useful. I think you will be intrigued to 
see just how much is squeezed into the band, especially above 10.140. In 
particular, the graphical approach highlights several overlaps between 
modes, which (to me at least) weren't at all obvious from the tabular 
frequency listing. I was also unaware of just how many Winlink RMS 
stations are active: no less than 48 stations on 32 frequencies, mostly 
above 10.140.

The chart is a living document. If you see any errors or omissions, or 
want to suggest improvements, please email me at g3nrw at yahoo.co.uk

Enjoy the Multi Mode weekend!

Ian, G3NRW

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