RF finally alive !

I had bought two RF modules from Aerocomm (AC4790-1000) a few months ago and had designed a printed circuit board which allowed it to be powered from batteries and communicate with a serial communication port. However, as with every prototype, a few bugs arose that prevented me to actually communicate from one module to the other and back again, effectively removing all interest in the original planned activity.

After a few hard working hours I found the bugs and could finally work the modules the way they were intended to, as easily as the company claimed them to be (well it so happens that they are, I simply designed the PCBs in a hurry and missed obvious bugs, as they always appear to be afterwards).

Bug one was I had totally inverted the footprint of the DB-9 connector, solved by soldering it on the other side of the PCB, praising the lord that I didn't choose a surface mount connector this time.

Bug two was thinking RTS connects to CTS and vice versa. In fact, RTS goes to RTS and CTS to CTS, quite simply, but I thought the same logic that applied to RX and TX went the same for these flow control pins, but I turned out to be wrong.

The last bug is a big one.. the buck converter taking batteries to a bare 3.3 Volts was simply not powerful enough to bear the peak current of the (quite powerful) transmitters which is around 1.5 amps. After plugging a PC power supply on my boards, everything worked fine.

A new board with possibly a brand new buck circuit will have to be designed, but the concept wireless communication has been demonstrated to work just as initially planned.