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Nanobridge M5 wireless LAN link, Part II

After a bit of delay, we were able to return to the WICC transmitter site to install the Wireless LAN link.  The installation was pretty straight forward.  The studio unit was mounted on an existing STL tower on the top of the elevator room, the transmitter unit was mounted on an existing pipe on the roof of the transmitter building.

M5 Nanobridge mounted on transmitter building with radome

M5 Nanobridge mounted on transmitter building with RADOME

I included RADOMEs for a couple of reasons; first, there is a lot of critters around of the two legged and winged kind. The upright two legged critters may be attracted to the signal strength lights at night. This unwanted attention could invite the juvenile delinquents bored teenagers to throw various objects found laying around on the ground at the antenna, damaging it.  The winged type critter may be inclined to view the feed horn as a good nesting location. The other reason is this site gets a lot of rain, wind, ice and snow, therefore the RADOMEs afford some protection against the weather.

Aiming the antennas was pretty straight forward, but requires at least two people.  Using landmarks, we aligned the dishes in the general direction of each other.  Both ends of the system were turned on and we had a -89 dBm signal path, and somewhat surprisingly, the radios linked up and my laptop grabbed an IP address via DHCP.  Using the signal strength meter on the side of the antenna, each dish was peaked in turn:

M5 Nanobridge Antenna signal strength meter

M5 Nanobridge Antenna signal strength meter

Then, somebody on either end went below and looked at the signal strength screen on the web interface while the other end was peaked.  In the end, we had about -65 dBm signal strength, which is somewhat less than the -58 dBm predicted.  I think we can do better, so on the next clear day, I am going to peak the signal again.

The data rate initially reported was over 100 MBPS, however, once I started transferring files back and forth, that dropped to about 50 MBPS.  If it is raining, that rate drops to about 35 MBPS, which is still far above what we need this link to do.  As a test, I streamed a youtube video, downloaded a windows update, loaded several web pages and checked my email simultaneously.  There where no issues with the data rate while those tasks were being preformed.

It is quite amazing to me that these little inexpensive radios can work so well.  My boss thinks that they will be blown up by lightning during the first thunderstorm of the season.  I don’t know.  There are several of these units that have been installed at mountain top tower sites and have been working for several years without issue.

Next step, installing the IP cameras and warning signs on the fence, setting up the monitoring software, etc.

Transmitter site security cameras

Transmitter site security cameras

Cameras mounted on old chimney platform.  This is the first set of cameras covering the south, north and west approaches.  A fourth camera will be mounted on the back of the building covering the east approach.  Then, under the eves cameras will be mounted on all four corners of the building and the generator shed.  If anything moves, it will be recorded.

Axiom


A pessimist sees the glass as half empty. An optimist sees the glass as half full. The engineer sees the glass as twice the size it needs to be.

Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the Government for a redress of grievances.
~1st amendment to the United States Constitution

Any society that would give up a little liberty to gain a little security will deserve neither and lose both.
~Benjamin Franklin

The individual has always had to struggle to keep from being overwhelmed by the tribe. To be your own man is hard business. If you try it, you will be lonely often, and sometimes frightened. But no price is too high to pay for the privilege of owning yourself.
~Rudyard Kipling

Everyone has the right to freedom of opinion and expression; this right includes the freedom to hold opinions without interference and to seek, receive and impart information and ideas through any media and regardless of frontiers
~Universal Declaration Of Human Rights, Article 19

...radio was discovered, and not invented, and that these frequencies and principles were always in existence long before man was aware of them. Therefore, no one owns them. They are there as free as sunlight, which is a higher frequency form of the same energy.
~Alan Weiner

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