RFM69 lowest possible range

[markus1234]

Hi,
to recieve a secure number, I want to limit the range  of a RFM69 to its lowest possible minimum (ideal would be only a few centimeters).
A simple 433mhz antenna wire is attached (and non removable).

Is there any other way beside setting the tx power to near 0? (This will give me at least 4 -6 m of range, which is too much)

thanks in advance

[captcha]

Replace the antenna with a 50ohm SMD resistor and you'll have a range of around 5m.

[markus1234]

thanks for your answer but I'm looking for an software solution to switch from high range to "nearly no" range

[ChemE]

thanks for your answer but I'm looking for an software solution to switch from high range to "nearly no" range

I think then that you need to experiment with detuning your broadcast antenna so that there is a significant mismatch between Tx and Rx frequency.  That is software and should be able to cripple range pretty effectively.

[joelucid]

thanks for your answer but I'm looking for an software solution to switch from high range to "nearly no" range

In my experience if you use an HW as W or the other way around on the TX side you get very minimal range.

Joe

[perky]

Turn off all the PA amps. You'll get a tiny signal coming out, only a few 10s of cm. This was one of my very first debugs