Hello Rob,

> indicates the cost of calls made by recognising the number dialled,
> looking up the time per unit for that dial-code in a table, using the
> correct call rate for the time of day, and timing the call.
> (Why? The devices hired by our telecoms company that rely on metering
> pulses are expensive & there's a long waiting list for them).

In Italy you can call the phone company and ask for their pulse even
if you didn't rent their meter. The service is inexpensive (five dollars
every two months) and is available two weeks after the request.
Are you sure that you have to rent the meter to get the tone? I'd be
surprised to hear that the italian Telecom offers something better
than the rest of the world.

I've built a meter using a PIC, it costs about 40$ (but I've bought
some components from RS, their prices are quite high).

Bye,
  Flavio