I have been burning in my RTS-SDR Dongle (actually DVB-T Stick) and using a yagi 1.2GHz antenna which was unused on the roof of my house. Currently using adsbSCOPE on my work laptop but plan to migrate to my RaspberryPi when I have the time.
I am located about 10 miles south of LAX with the Yagi pointed towards Santa Ana, CA (Santiago Peak) which is roughly east of here. I am able to “see” about 40 miles north (Valencia), west (Oxnard), and south (Laguna Beach) of me and about 90 miles to the east (Banning, along I-10). Interesting trying to compare results against FlightAware Flight Tracker but Flight Tracker lags by about 15 minutes. There are definitely targets that I am seeing that Flight Tracker does not list and also the other way around.
ANTENNA: I have an unused 1.2GHz antenna (definitely not resonant at 1.09GHz) which I thought to try rather than build an antenna right away. Antenna is mounted about 30 feet above ground and fed with about 50 feet/15 meters of RG-6 coax with about 15 years of sun exposure on it. Definitely pulls in more aircraft than indoor mag-mount that was packaged with the Dongle. I guess what I trying to say is to try things out and not necessarily worry about your antenna not being “tuned” to 1090MHz. You may be pleasantly surprised.
DISCLAIMER: I am on relatively high ground above the Los Angeles Basin with an excellent Line Of Sight past the Downtown Area.
Is the yagi horizontally or vertically polarized? ADS-B transmissions are vertically polarized, so a mismatch at the receive antenna could cost you at least 10 dB (if not more).
The yagi is vertical. I don’t have much information on it as I was gifted the antenna years ago by a ham who lived much closer to Santiago Peak and used it for ATV. It has 7 elements, including driver, but not enough gain to get anything more than a P3 signal from the ATV repeater on Santiago. Like I said, it has been up for quite a while and is overdue for cleaning as I am subject to salt fog and sea birds!
From a reception aspect, the receiver and antenna combination follow the dominant overland air traffic patter on approach to LAX. The departure pattern for most flights is a northernly or southernly turn after clearing the coastline as most flights go towards the north or east from here. I should not have been too suprised but was glad that I could “see” planes over the mountains to the North and East of LAX due to their altitude. During this past weekend, I was also able to “see” several private planes (SR-22s, Cessna 206’s, etc) on ADS-B, too.
73,
kevin
kc6pob
