[time-nuts] Toy radiolocation and LORAN envelope

Chris Albertson albertson.chris at gmail.com
Tue May 27 18:02:12 UTC 2014


You don't need much power because the device in the toy only needs to
transmit for a few milliseconds then shut off.   Some transmuter you
have pings the device in the toy that acts like a transponder.  It
only transmits in response to a "ping".   So limey it can be powered
by a button battery.   How to power the receiver? RFID tags are
devices that are powered by rectifying the RF energy from the antenna
. Crystal sets work this way also.  as for logic, the TI MSP430 can
run on nano amps of current. and sleep modes use pico amps.   So it
could be powered by a capacitor that is charge from some powerful AM
broadcast station.

It turns out that "energy harvesting" (getting power from the
environment) is a hot tops right now.  The simplest method would be
the solar powered calculator.  That tiny little cell runs a uP and an
LCD screen.  The old mechanical self winding watch was another example
of harvesting energy.  You could run the receiver and logic on
harvested energy and then use the coid cell battery for a transmitter.

Your locator device would measure time of flight to the toy and its
own location via GPS.  As you move the locator it gathers data used
for a solution.   All the "smarts" is on the hand held locator that
has a high power transmitter, sensitive receive, GPS and a computer.
 The device in the toy is a simple transponder.

In "monitor mode" the locator would request a micro-power ping (not
using the coin battery, just the capacitor. from the toy and use a
large non-mobile antenna and would alarm if the time of flight
changed.

You'd want some frequency that would go through walls and trees and in
some band that is legal for such stuff.
...
>> A friend of mine recently suffered a theft so I thought about the
>> opportunity
>> to embed little marker transmitters in some object usually left in the
>> yard
>> (like bicycles for example), and have inside the house a system that
>> constantly monitors them for unwanted movement,
-- 

Chris Albertson
Redondo Beach, California



More information about the Time-nuts_lists.febo.com mailing list