Very Uni Directional Antenna

[JammyB]

Hi All
Could any of you experts help me get started by dropping me a few keywords. I want to build a small antena I can use to pinpoint sources of transmission in the 380 to 400MHz range.
I could with the name of the type of ariel used for such a thing and pointing to any web resorces that might help me design it!

 

[N_Jay]

Try a simple direction finding loop antenna.

You work off teh nuls not the peaks.

http://www.google.com/search?hl=en&q=direction+finding+antenna

 

[n2mdk]

Here are a few Yagi (a beam antenna) RDF-Radio Direction Finding.

 

[N_Jay]

Here are a few Yagi (a beam antenna) RDF-Radio Direction Finding.

Not to argue with you, but a Yaggi is a bad direction finding antenna.

It has a realitivly wide 3 dB beam width and strong side lobes.

 

[JammyB]

Try a simple direction finding loop antenna.

You work off teh nuls not the peaks.

http://www.google.com/search?hl=en&q=direction+finding+antenna

Thanks for the response.
I would rather use somthing that works on the peaks though so i can use squelch and Close Call functions!

Could you sugest anything else? can you screen a Yaggi somehow to make it more directional?

Ta

 

[Don_Burke]

If you have to go with the peak, two yagi antennas fed in phase are about as good as you are going to get and stay reasonably portable.

Hi All
Could any of you experts help me get started by dropping me a few keywords. I want to build a small antena I can use to pinpoint sources of transmission in the 380 to 400MHz range.
I could with the name of the type of ariel used for such a thing and pointing to any web resorces that might help me design it!

 

[JammyB]

If you have to go with the peak, two yagi antennas fed in phase are about as good as you are going to get and stay reasonably portable.

Are there any good websiteswhere there would be somedetailed info on this arrangement?

Thanks again

 

[hoser147]

Check out some antennas used in dog tracking on dog tracking collars. hope this helps Hoser

 

[N_Jay]

Thanks for the response.
I would rather use somthing that works on the peaks though so i can use squelch and Close Call functions!

Could you sugest anything else? can you screen a Yaggi somehow to make it more directional?

Ta

You can do some reading and learn from those that have gone before you,

OR,

You can ignore the advice and learn all over on your own.

Look at how hard it is to find the peak with an FM receiver, and you will quickly figure out when you look for an antenna with a sharp null.

When you really want to get crazy, then you move to phase detection type direction finders.

 

[N_Jay]

Are there any good websiteswhere there would be somedetailed info on this arrangement?

Thanks again

http://www.google.com/search?hl=en&q=yagi+phase+antennas