I've had a lot of support on my question about an old PL tone list, and several private emails back and forth. I'd like to thank those that helped, and invite comments from all.
The article I was writing morphed into three articles: 1) A Historical and Technical Overview of Tone Squelch Systems - A primer on tone systems, with a little on digital systems. <http://www.repeater-builder.com/tech-info/ctcss/ctcss-overview.html> 2) CTCSS doesn't fix anything! (It just hides it) <http://www.repeater-builder.com/tech-info/ctcss/ctcss-doesn-fix-anything.html> 3) CTCSS tone numbers are useless ! This was written after I finished a local CERT class refresher, and a fireman said to always use the same FRS channel number and tone number within your team, and the team leader needed to have the info for the adjacent teams, or the team above and below in a multi-story building search. He was very surprised to know that the tone numbers vary between manufacturers. I had to prove it to him... I got to thinking about ham radios and this chart came to pass. <http://www.repeater-builder.com/tech-info/ctcss/ctcss-chart.html> Comments on any of the above articles are welcome. Mike WA6ILQ
