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[indel99]

One can improve the transmitted power from a MS16A module just by increasing the supply voltage. I am not happy with the battery powering, so all my systems in the house are on a wire supplied power.
If for a 3V (the two AAA batteries) the (theoretical) transmitted power would be about 130uW (peak), for a 4V supply one can have about 300uW and for 5 V, about 500uW.
The supply voltage increase will not affect adversely the microcontroller, dual opamp or the transistors. As for the transmitter "power" stage, the ratings for the transistor KSP10 are much over what one can have inside. The oscillator/transmitter transistor is cut off without signal. When the code from microcontroller comes in a pulse train, there will be a burst of high frequency oscillations at about 200MHz.  These pulses last only milliseconds, so no damage there. As for the burst frequency, although there is a change due to the supply voltage alteration, that change is not affecting the receiver capability.

[Drews]

I did A LOT of testing with the motion sensors the past week. Is it possible I alreayd drained the batteries pretty good? I have MS14A motion sensors. When I first had everything hooked up they worked great. Now I have to be about 10 feet from the Firecracker before the MS14A triggers the Firecracker. Seeing as how I need the camera plugged in anyway, I was thinking of going with a constant 3V power supply for the MS14A via a small AC to DC power converter from Radio Shack. Does going with 5V make a big difference? If so I'll go with that. LIke I said, I put fresh AAA batteries in the MS14A last weekend (that's one week ago). I suppose it's possible from all the testing that that I ran the batteries down enough to affect broadcast range. Still, the motion sensor woudn't be anymore active than if it was in a regular installation, so actually, the batteries drain pretty fast and a power supply would be better in that case.

I already tried a passive antenna and that gave me about another 5 feet of range.

Thanks

[indel99]

As I said, the RF transmitted power of the MS16A module will increase when you use a dc power supply larger than the two AAA batteries (which, when new, yield some 3.2V). If you chose a 5V dc supply, your RF power will, at least double so increasing the range. I have measured with the oscilloscope the waveforms and it is as I have mentioned above.
To divagate a little, I will replace the dc supply with a 12.5V so I can supply power to white LED (very high output) to make all the lights and security systems on a battery.
By the way, did anybody protected their telephone incoming liines from disconnection at the outside wall box?