> In Melbourne Australia a similar (or identical - I don't know) toll system is
installed by a Swedish company affiliated with SAAB aircraft industries. A radar
 detector would probably detect those microwave trancievers; depending on it's f
requency reponce.
>

I don't know - the base xmitter is mounted right above the lane, pointed about 3
0 deg off vertical
"into the driver's eyes".

I suspect it's not very powerful, and probably is very directive.
Just from looking at the thing, it's obviusly some cm band microwave.

The transponder has a piezo unit and emits a small chirp when it's
fired off.
I'm curious what powers the chirp.

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Anniepoo
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