123 Mother Caught a Flea
Image: Mama Lisa's World
One, two, three,
Me mother caught a flea,
She put it in the teapot
And made a cup of tea.
The flea jumped out,
Me mother gave a shout
And in came daddy
With his shirt hanging out.
So goes the nursery rhyme from Ireland. You would have noticed the total absence of an Irish accent.
You also would have noticed that the rhyme has nothing whatsoever to do with Amateur Radio. Well almost nothing. 123 Hz is a commonly used frequency for CTCSS in radio equipment, both commercial and Amateur. Back in two thousand mumble, around 2008 I think, the WIA facilitated a meeting of Amateurs from around the Sydney Basin to discuss congestion of repeaters, mainly in the two metre band. One outcome of this meeting was that the WIA Technical Advisory Committee changed the recommended CTCSS tone for repeaters from 123 Hz to 91.5 Hz.
Recently the subject of CTCSS tones was raised in Western Australia. The event I just described were remembered, but nobody remembered or understood the reason for the change to 91.5 Hz. Will VK6UU contacted John Martin, the head of the Technical Advisory Committee and received the following response:
So there is it from the horse’s mouth. The wise men from the East issued no decrees. Western Australia wasn’t deliberately excluded from any process. The change to the recommended CTCSS tone is recommended and is entirely optional.
Thanks Will for pursuing the issue and gaining clarification.