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VHF/UHF Baluns, Transformers, and Hybrid couplers.

VHF/UHF Baluns, Transformers, and Hybrid couplers.

VHF/UHF Baluns, Transformers, and Hybrid couplers.

I have a 144-704 MHz Vert. base station antenna that I have modeled. It requires two sources that need to be at a 180 d. phase difference. It covers close to a 5/1 frequency bandwidth with 1.5/1 SWR across the band. Each source needs to 50 Ohms. This antenna is used for transmiting and receiving. I need to find a method of feeding such as:---
1. I can pararallel the two 50 Ohm sources, and reverse one of feeds, to create a 25 Ohm source. Then I would need a 25/50 Ohm VHF/UHF transformer, or balun. to achieve a 50 Ohm source. Is there such devices for these frequencies?
2. Or, I can find a 50 Ohm 180 degree hybrid coupler, that will cover the 5/1 frequency spread. I don't know if
such a coupler will work in both directions for transmit and receive. Is there such a device?
Hirock eshortridge@verizon.net

RE: VHF/UHF Baluns, Transformers, and Hybrid couplers.

It seems as though you're looking for an RF 'Power Divider'.

They're available covering frequency ranges wider than 5:1, but I don't know off-hand which model would meet your specs.

RE: VHF/UHF Baluns, Transformers, and Hybrid couplers.

www.MiniCircuits.com has alot of RF transformers that work in this frequency band for low power applications. Only $2.

If it's high power applications, that's alot more expensive and harder to find.

Low power typical = 1/2 watt, High Power = over 5 watts (see www.werlatone.com).


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