Yagi and Omni on the same transceiver...

[KO4TNL]

The question is; can I use a yagi and an omni directional antenna at the same time? They would both be receiving or transmitting at the same time.

If this is possible then how?

 

[ladn]

Intriguing concept, but you are a little vague on details.

Are you talking about a base station or a repeater? And what bands? Most importantly, why--what are you trying to accomplish?

 

[KO4TNL]

Intriguing concept, but you are a little vague on details.

Are you talking about a base station or a repeater? And what bands? Most importantly, why--what are you trying to accomplish?

GMRS low power repeater on a 30 foot tower.
No specific brand.
Objective:
Get communication from roughly a 5-7 mile radius on each end of a 20 mile separation.

 

[AB5ID]

What is your end goal by using both antennas? It *can* be done but there are so many variables for patterns and phasing issues it may not accomplish what you want to do.

 

[KO4TNL]

What is your end goal by using both antennas? It *can* be done but there are so many variables for patterns and phasing issues it may not accomplish what you want to do.

Get communication from roughly a 5-7 mile radius on each end of a 20 mile separation.

 

[prcguy]

If you split your feedline to two different antennas you immediately loose at least 50% of your signal to or from each antenna. If you have a 6dB gain omni then it becomes the equivalent of a 3dBgain and a 10dB gain Yagi will become a 7dB gain Yagi. If you were to split the feedline to two identical antennas spaced the precise required distance apart you could get up to 3dB gain in the process. But your using two completely different antennas with random spacing.

In doing this with the antennas you have not only will you loose at least 50% of your signal by splitting, there is a good chance you will loose more signal due to each antenna receive or transmitting a signal out of phase with the other antenna, which will cancel out some signal with the worst being if the antennas are the exact distance apart to cause a 180deg phase reversal and you get basically no signal.

With this info you can decide if you want to combine the antennas.

 

[KO4TNL]

If you split your feedline to two different antennas you immediately loose at least 50% of your signal to or from each antenna. If you have a 6dB gain omni then it becomes the equivalent of a 3dBgain and a 10dB gain Yagi will become a 7dB gain Yagi. If you were to split the feedline to two identical antennas spaced the precise required distance apart you could get up to 3dB gain in the process. But your using two completely different antennas with random spacing.

In doing this with the antennas you have not only will you loose at least 50% of your signal by splitting, there is a good chance you will loose more signal due to each antenna receive or transmitting a signal out of phase with the other antenna, which will cancel out some signal with the worst being if the antennas are the exact distance apart to cause a 180deg phase reversal and you get basically no signal.

With this info you can decide if you want to combine the antennas.

This is exactly what I thought would happen. Sounds like I need (2) two repeaters at both ends and seperated by at least 20 feet but more is better.

 

[KO4TNL]

Or higher and more wattage.

 

[ladn]

Sounds like you want an elliptical antenna pattern.

Stacked, folded dipoles should be able to give you the desired results. You can find the details on several other, recent, threads, but don't skimp on the hardware!

 

[prcguy]

This is exactly what I thought would happen. Sounds like I need (2) two repeaters at both ends and seperated by at least 20 feet but more is better.

I don't understand this post, why 2 repeaters?

 

[alcahuete]

This is exactly what I thought would happen. Sounds like I need (2) two repeaters at both ends and seperated by at least 20 feet but more is better.

I have no idea what you're doing here. Your posts are not clear at all. If I'm reading this correctly, you have two repeater sites that are separated by 20 miles, you want to link them together, and get 5-7 mile coverage from each repeater?

If that's the case, then use a microwave link or such to link the repeaters together, assuming you can't do an internet link.

 

[prcguy]

I'm thinking its simply two stations about 20mi apart using a repeater and they want 5-7mi simplex around each base station. Depending on the terrain all that's needed for that is a good omni like 6dBd gain up high at each base station and a high gain like 8-10dBd gain stick on the repeater and its high enough to reach the base stations. That part of Florida is really flat so its going to be big gain antennas and tall masts and a repeater on a tall building or with a very tall tower.

I have no idea what you're doing here. Your posts are not clear at all. If I'm reading this correctly, you have two repeater sites that are separated by 20 miles, you want to link them together, and get 5-7 mile coverage from each repeater?

If that's the case, then use a microwave link or such to link the repeaters together, assuming you can't do an internet link.

 

[tweiss3]

This is exactly what I thought would happen. Sounds like I need (2) two repeaters at both ends and seperated by at least 20 feet but more is better.

Pay attention to your rules. Repeater to repeater links would be considered a fixed station and limited to 15W power output (95.1767 a 2), and would also have to use one of the allowed frequencies for the link. You could link the repeaters with the internet, if you knew how.