More Arduino fun on Sunday

What better way to spend a Sunday afternoon than to debug some code in your project.
Got around to hooking up the Adafruit LCD display via I2C bus to save some connections,
and also got rid of the garbled text when load was applied to the relays (a 10uf cap did the
trick). In addition I also solved the reset issue when rotctl re-connected (another 10uf cap)
and now need to figure out where some of the weird readings come from and how to make
the buttons work for manual control. Progress is being made.

Saturday build

Finally got around to build the interface for cwdaemon so that
CQRlog can key the radio for CW if need be. It’s not very complex
but still a productive day. Now back to debugging the rotor controller.


It’s a simple switching circuit with a 2n2222 transistor. I also
put in a 3.5mm jack so I can hook up the straight key.


Since I didn’t need the PTT portion, I only built the upper part.

NAQCC January sprint results

Was pleased to see the results for the W7 region of the last NAQCC sprint. 2nd place ain’t too shabby
even though it was only with 16 QSOs. Way to go and make more in February.

SWA Category - W7 Division
Call   QSOs Mbrs Pts  Mul  Sco Bon Final  80-40-20 Antenna
K9JWV    40   36  76   23 1748  x2  3496  43' vertical, 60 elevated radials
K5TRI    16   15  31   10  310       310  OCF Dpl @30'
W7GAH     7    7  14    6   84  x2   168  240' RandWire @60'
K7ZI      5    5  10    5   50  x2   100  Windom @50' apex, interted L
AA7CU     9    9  18    5   90        90  Mobile Screwdriver @12'
W7YSB     4    4   8    3   24  x2    48  Fan Dipole @30'
NU7T      4    4   8    3   24  x2    48  80m fence top Dpl 
WB7EUX    5    5  10    4   40        40  Windom @30'
WU7F      1    1   2    1    2  x2     4  Vertical mounted near ground
KD7HXN    2    1   3    1    3         3  Horizontal Loop @22'

Simple Sat Tracker

Working amateur radio satellites is fun. What is even more fun though (at least to me)
is building all the automation into a station to make it even more technologically advanced. After all, Amateur Radio is a technical hobby where one is free to experiment and build. In the past I used a TS-2000 (and FT-736R before that) for sat contacts. Gpredict served very well as software for pass prediction and rig control for doppler shift. What I was lacking however was a automatic way to track the antennas so I had to do that manually which often times left me forgetting it during a QSO wondering why the signal was fading given the satellite was still visible.
There are quite a few solutions for Yaesu’s G5500 AZ/EL rotor combo. Which btw. is quite pricey and I never saw the need to spring for it given the limited availability of satellites and operating times. I went with two yagis mounted at fixed 20 degree elevation on a cheap AR-303 rotor and that did the trick as well. What this was lacking though was the ability to remote control the rotor from software. Enter Arduino stage left.
I began by understanding how the rotor controller works on a 3-wire rotor and then built the interface using an Arduino UNO and a relay shield so that I could trigger direction and tuning

Next came the interfacing of all this and adding a LCD display to show status information.

I’m currently trying to fix some last bugs in the code. But more or less it’s working (sometimes) to the point where it’s successfully tracking a satellite.
I will share more about this project in the coming days as I go along fixing the last bugs and making it finally work.