Two type of meters have been identified as far as I know, I've seen one, the
LowFER boys talk about the other.
One type sends data over the power line, simlar to an X-10 home control
systems, this is low frequency, about 120 KHz and data is sent on regular
The other type, which we have here operate around 903 MHz and only send data
once a month as a reader with a hand-held data terminal drives by and
interrogates the meter.
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