Best way to match 50 ohms to 300 ohm input impedance at 1.7 GHz?
时间:04-07
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Hello everyone,
What is the best way to match a 50 ohm unbalanced line to a 300 ohm balanced antenna at 1.7 GHz? The bandwidth of the matching circuit only need to be 40 MHz or so (~2.4%), but more is better. Intially I was thinking a coax half-wave balun since they are 4:1 transformers, but is this feasible at 1.7 GHz?
Thanks for any suggestions!
What is the best way to match a 50 ohm unbalanced line to a 300 ohm balanced antenna at 1.7 GHz? The bandwidth of the matching circuit only need to be 40 MHz or so (~2.4%), but more is better. Intially I was thinking a coax half-wave balun since they are 4:1 transformers, but is this feasible at 1.7 GHz?
Thanks for any suggestions!
yes quite feasible, I use coax baluns just down the band a little way on 1296MHz
be precise in your cutting of the balun length, remember its an electrical half wave NOT a physical half wave :)
an electrical 1/2 wave will be a little shorter cuz of the velocity factor of the cable you use.
Speaking of which, the best cable for the job would be UT 141 0.141" diameter semi rigid coax
cheers
Dave
