Is the Offset Fed Satellite Dish on the Police Station Safe?

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Discussion Overview

The discussion revolves around the safety of an offset fed satellite dish located on a police station, particularly concerning health risks for a resident moving into a house directly below the antennas. Participants explore the nature of the antennas, their function, and potential health implications.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant inquires about the type of antenna and its safety, expressing concern due to proximity to the antennas.
  • Another participant identifies the antennas as VHF radio antennas used by emergency services and claims no known health hazards are associated with them.
  • A different participant suggests that being on the first floor below the antennas places one outside the transmit antenna pattern, indicating low RF energy exposure.
  • Some participants express reassurance about safety based on distance and positioning relative to the antennas.
  • Questions arise regarding a separate dish antenna aimed horizontally, with speculation about its purpose and functionality, including references to offset feeds and potential uses in amateur radio.

Areas of Agreement / Disagreement

Participants generally agree that the VHF antennas pose no significant health risk and that the position below the antennas is safe. However, there is some uncertainty regarding the purpose and functionality of the horizontal dish antenna, with differing opinions on its identification.

Contextual Notes

Some assumptions about the safety of VHF antennas and the effectiveness of their positioning are not fully substantiated within the discussion. The identification of the horizontal dish antenna remains speculative.

Who May Find This Useful

Individuals concerned about the safety of living near radio antennas, as well as those interested in amateur radio and antenna functionality.

phys86
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Hello everyone,
for health reason, I just need to know from you what kind of antenna is the one in the photo attached, if it is a receiver or a transmitter and if it is safe enough.

I will have to move on the first floor of a house right under that building (which is a police station if it can be useful to know) and I am a bit concerned. Many thanks.
 

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:welcome:
Those appear to be VHF radio antennas of the type used by fire, police, pilots and taxi drivers.

I never heard of a health hazard associated with VHF radio antennas. I would not worry.
 
And on the first floor of the building below the antennas, you are out of the transmit antenna pattern anyway. There is very little RF energy below vertical antennas like that. :smile:
 
Thanks to both of you, so I guess I shouldn't worry.
 
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Just in case, this is an other view, with the house and the police station with the antenna.
 

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phys86 said:
Just in case, this is an other view, with the house and the police station with the antenna.
You are still well below the main Tx pattern, and are pretty far away. I wouldn't worry about it.
 
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berkeman said:
You are still well below the main Tx pattern, and are pretty far away. I wouldn't worry about it.
That's good to know, thanks again.
 
What is the dish antenna, aimed horizontally, in the planter at the front of the house? Not many satellites viewable in that direction!
 
Tom.G said:
What is the dish antenna, aimed horizontally, in the planter at the front of the house? Not many satellites viewable in that direction!
Looks like a hummingbird director. Or reflector, it's hard to tell.

Or staging for the rubbish collectors. Maybe he didn't pay his bill...
 
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Tom.G said:
What is the dish antenna, aimed horizontally, in the planter at the front of the house? Not many satellites viewable in that direction!

you may not be familiar with offset feeds ?

berkeman said:
Looks like a hummingbird director. Or reflector, it's hard to tell.

It's an offset fed satellite dish. The beam direction with the current mount would be up over that blue wall

dish.JPG


if you notice, the arm out to the feed point is near horizontal (maybe a few deg above the horiz.), this means the beam angle will be a good few degrees above the horizontal

in this pic is yours truly repurposing an offset fed sat dish for use on the 10GHz ham band
NOTE the angle of the feed boom … it is angled down from the horizontal and as a result the radiated signal is beaming out at a horizontal angle

091002-IMG_2226 Dave and Paul at La Perousesm.jpg

Dave
 

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