That would be much easier, simply sweep a modulated oscillator across the
band. With a couple of adjustments it would be easy to emulate a train
whistle, a somewhat universal warning.

wrote in message
...
On Mon, 3 Oct 2005 17:19:42 -0400, Ari Silversteinn
wrote:

DHS has proposed a change in scenario. They want an on locomotive
alerting
system that could be commandeered and driven at, near or about a disaster
site. Everything else stays more or less the same, overbroadcasting on
local AM/FM, power off the locomotive, selective or full frequency
broadcasting, train (s) to be in motion at all times. 20-30 second
messages
that would also combine a message to be aware that a locomotive (at
speed)
will be flying by the at grade crossings.

Comments?

Tracks across Lake Ponchartrain fell in.

Granted they were put back in service faster than anything the
government had connection to.