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.

One month without a post

It's been an entire month since I last posted on this blog, for quite simple a reason: I had no time. A thought I had while I was still having no time but I needed to take a break, so here is a post which hopefully will open the way to a series of others, more interesting.

As for why I was and still am very busy, I am just a week from graduation of a degree in Electrical Engineering, but as you may know from other posts I will begin a Master's degree in May, so I am not quite done just yet with university.

I will also be moving for that reason from my little native town Trois-Rivières to Montréal, where the École Polytechnique de Montréal is.

There's been a lot of paperwork to do for bursaries and time spent on finding the right apartment, and with all this I still had classes, worked 16 hours a week and got a couple (dozens) things done for my end of studies project, along with my usual volunteering.

I am glad this is nearly over and I will be able to move on to the next step (Master degree) from May 5th, where I am sure the combination of the flood of white papers and available time will renew my interest for research.