Locate the trace that feeds switched battery voltage to the final
transmitting stage. Cut this trace somewhere between the transmit switching
circuit and the final amp stage. Insert a few rectifier-type diodes (1N400x)
in series across the cut point. Each diode in series will lower the voltage
to the final amp stage about .7V or so. For each halving of voltage to the
final stage, the output power (and consequently the power load on the
battery) will drop by 4:1. All of this assumes that the final amplifier is
well-behaved under reduced voltage conditions, which should be true but is
not guaranteed.

Joe
W3JDR

wrote in message
ups.com...
Nowadays two-way radios are getting more and more powerful, coverage
up to 8, 10 12 or more miles. Ironically, it is even harder to buy one
with only 2-mile distance.

I want to use a two radio just for short distance, for example, only
within 1000 feet. How to modify the circuit (generally speaking) so I
can extend the radio's powerful consumption? As I do not need it to
communicate for longer distance, I want it to reduce power output, so
I can use it for longer time. I know it is difficult to illustrate
without a schematics, but just in general terms, what kind of options
or in what areas can I do the modification?

One of my applications is to use 2-way radio as baby monitor for
longer distance than normal baby monitor does.