PMR446 Yagi

[Your_account]

Hey
I want a Antenna for 466Mhz (and ISM 433,05 MHz -> 434,79 MHz).
So i order a lot on Ebay for a good value and found an Seller from Slovakia.
But what Antenna give me the best Results?

Portable base yagi beam antenna pmr 446MHZ 70cm 4 elements high gain

Portable base yagi beam antenna pmr 446MHZ 70cm 4 elements high gain folded

Yagi beam antenna pmr 446MHZ tunable 4el high gain professional gammamatch

Yagi antenna pmr 446MHZ 430-470mhz8 el high gain professional gamma match

Portable base yagi beam antenna pmr 446MHZ 70cm 6 elements high gain folded

Thanks

 

[mmckenna]

Your definition of "best results" might be different from mine.

The more elements a Yagi antenna has, the more gain it will exhibit. The more gain an antenna has, the better it will receive signals. On the transmit side, the more gain, the more RF energy is focused towards the front of the antenna.

Drawbacks of higher gain is that the beam width of the antenna will get narrower. That means the narrower your signal will get focused.

That might be exactly what you are looking for. Sometimes using a lower gain antenna, and thus a wider beam width reduces the accuracy with what the antenna must be aimed.

There are a number of variables involved. Knowing exactly what you are looking for would help.

 

[Your_account]

I will use it to see the ISM Band in SDR# and find some People who use there PMR Device.
Maybe someday i will use it to send to in the future. How about the Output Power of an Handheld Device can it be dangerous for me when i hold the Antenna in my Hand?
Sorry for that stupid question i never use an device who send...

 

[mmckenna]

That's not a stupid question, it's actually a good one.

The Yagi antenna design has what is called a "front to back" ratio. This is the difference between how much signal goes out the front of the antenna, and how much is radiated off the back. The higher the gain, the better the front to back ratio is, and the less signal will be sent out the back of the antenna.

Since most hand held radios are only a few watts, the amount of RF energy coming off the back of the antenna would be pretty small. Likely no more than what you'd get off the regular flexible antenna on top of a portable radio, which would be close to your head.

Using one of these antenna will increase what you can hear, and the directional nature of it would help you narrow down what direction the signal is coming from. Should be interesting.

Make sure you get a flexible coaxial cable jumper to run from the antenna to your radio.

 

[Your_account]

In the future when I receive more People i would like make an Gateway and Upload the Stream only.
Then i would use it as an sector antenna.
I am an IT Engineer and visit some Conventions and hear a little about Antenna for Wifi what kind of Antenna i have to use for what kind of Connection so i know a little.