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[thatbobby]

I have been working with the 434MHZ TX/RX modules using the Arduino Pro Mini 328 5V/16MHZ. The TX/RX test beds are mobilized with 2 AA batteries and a 5V boost regulator. The TX sends a 3 byte message every second using Virtual Wire. The message contains a sequence counter. The RX receives the messages and determines the percentage of lost messages based upon the sequence numbers in the message.

The setup works okay when the test beds were a few feet apart, but the percentage of lost messages increases when I move the TX to other rooms and floors of the house. If I move the TX to the other side of the house I have a total message failure. After much tinkering (with antennas, message sizes, and message cyclic rates), I put a 9 volt battery on the TX and everything worked perfectly and at very long distances around the house.

I did not want to drag around AA batteries and a 9 volt battery, so I bought a 9 volt boost from Pololu and put it on the TX test bed. The setup works at close range, but I get a total message failure when the TX and RX are separated by a few rooms. If I plug in the 9V battery the setup works. Put the 9V boost back in and I get total message failure. I measured the boost and it is putting out 9 volts.

Does anyone know why the TX works really well with a 9 volt battery, but not so well with a 9 volt boost regulator? Thanks.

[thatbobby]

My appologies to everyone. It turns out that the AA batteries were low. The boost put out 9 volts in a quiet state, but dropped to 2 volts when the TX was running. A new set of AA batteries fixed the problem.