Couple of questions


#1

Afternoon all
OK I’ve been playing with different antennas over the last few days and settled on a coax collinear. Two questions , I’m receiving on average about 30 or 40 aircraft with a messages rate of around 250 but every now and again that just drops off to 20 and around 50 messages per second. Then over a short period go back up to the first figures. This is in a space of 15 mins. I understand planes drop off etc. But this is quite a drastic drop. My thoughts is interference but any thoughts. Next question is a bit loaded I know but is 40 to 50 total aircraft with 30 with positions and 200 messages per second poor, OK or good. Thanks


#2

Check out @abcd567 posts on gain optimisation.

He also has great stuff to see if you need a filter.

Look at the stats for the receivers near you. They will give you an indication of what you can expect.
http://flightaware.com/adsb/stats/user/perryd1 seems to do very well. It is possible that they have a better location(ie higher or less interference).


#3

Thanks for the replies, tried gain setting and -10 agc seems to work best for me. Agreed with the interference, I’m located at a high location and the antenna is also on the roof so inevitably really. I’ll have to invest in a filter and hopefully that will help.


#4

Thanks John, some nice tips.