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Matching 75ohm antenna to 300ohm receiver

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geotFM

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Hello i have this rabbit ear antenna and i want to connect it to my 300ohm receiver input. i wont use the 300 to 75 ohm balun but as i know the open dipole antenna is 75ohm but here its connected to a 300ohm cable .do i miss something here?How to match it properly to 300ohm balanced cable?
 

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Interesting observation. The only thing that comes to mind is that since the mismatch is not so high (~2dB) hence balun this is not included. Maybe to save cost?

For Transmitter however, it would be important.
 

Open Dipole Antenna has approx. 300 Ohm Impedance but there is a Balun in the TV Connector
 

Open Dipole Antenna has approx. 300 Ohm Impedance...

This is contrary to all known calculations and empirical evidence.
This IS true for a closed (folded) dipole.
 
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Here is the deal. If your length of 300 ohm cable is short (less than 1/8 wavelength) it does not matter.

Only if you have a long transmission line is it a concern

Balanced to unbalanced conversion is more important than impedance matching. An unbalanced load can screw up a dipole’s performance something fierce
 

Are you sure it's a 300 ohm line? What is the wire diameter, and the wire spacing??

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Here is the deal. If your length of 300 ohm cable is short (less than 1/8 wavelength) it does not matter.

Only if you have a long transmission line is it a concern

Balanced to unbalanced conversion is more important than impedance matching. An unbalanced load can screw up a dipole’s performance something fierce

Good point. So in this particular case the antenna is obviously balanced and so is the cable. But that connector looks like an unbalanced 75ohm. There's probably a balun hidden inside that black end-plug

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You should open it up and have a look-see
 

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