Cheap Homemade DIY AIS 162mhz SDR Antenna

Homemade AIS VHF 162mHz antenna. Getting 20nm + range ship tracking. Two wire coat hangers, some cheap CATV coax, and a Costco margarita mix bottle

I am getting 20+ nautical mile coverage with this simple cheap antenna.

Using a $10 ebay RTL SDR dongle, SDR#, AISMON and OpenCPN

Here are your references:
http://rtlsdr4everyone.blogspot.com/p/ais-antennas.html
http://www.rtl-sdr.com/rtl-sdr-tutorial-cheap-ais-ship-tracking/
http://www.rtl-sdr.com/tag/monopole/
https://rtlsdr4everyone.blogspot.com/p/beginner-antennas.html?showComment=1465796100895
http://www.marinetraffic.com/en/ais/details/stations/3232/_:b80b43127e4da02634b88fc6ac141bc7

AIS Antenna SDR Cheap Easy Homemade

SDR#, AISMON, OpenCPN

AIS SDR Antenna

UPDATE:
I don’t know how, but somehow I picked up a ship over 117nm away. I’m pretty sure this is over the horizon, so I do not know how this is possible unless its a reflection of the signal, or this homemade AIS antenna just got a lot of gain somehow…
ais117nm

Somehow, I am getting like 120 nautical mile range with this antenna, I cannot figure out why I am getting such good range in one direction.
AIS120

now getting over 400 nautical mile range AIS with this homemade monopole, how is that possible?
AIS432

So it seems that when the antenna fell down, it broke the solder on my horizontal radials that are connected to the ground/braid of the coax cable feeding the antenna. So, it looks like the minor adjustment of just a few millimeters, really improved or ‘super tuned’ this antenna. It seems to be slightly directional in the direction of the radials (North and South in my case), however it certainly improved or doubled my ‘straight out’ reception as well. Over all this is like a 200% improvement in range. So the leason here is, if you are getting poor 20nm reception, try extending the length or distance of those two 46mm radials. Either that or my SDR RTL dongle just got a whole lot more sensitive or clean signal…
AIS400close