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How to match antenna to amplifier output for maximum power?

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Vulcan

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Antenna Matching

hey all....

how do i match an antenna to an amplifier output for maximum power transmition and low return loss ??

input signal is a video signal at 203MHz.

please ask for any missing parameter..

thanks !!
 

mr_ghz

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Hi Vulcan,

The antenna is best matched when its impedance is identical to the output
impedance of your amplifier (most 50 Ohm).
This matching can be done with series/parallel inductors and capacitors.
All you have to know is the impedance of your antenna at this frequency
(real and imaginary) and the output impedance of your amplifier.

Bye
 

Vulcan

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thanks a lot !!!


what about frequency matching ?...
 

shorty

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try to insert a little Lamp in series to the signal
then you can trimm the filter or antennalengh to max. power

Shorty
 

mr_ghz

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Hi Vulcan,

The method described is to match a given antenna to the impedance of
your amplifier. This will give maximum power transmission and minimal
signal return (S11).
To match an antenna to a specified frequency you have to change the
dimension of your antenna. (How to make depends on the type of your
antenna). If the antenna is made shorter, the frequency will rise.

Bye
 

Element7k

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Re: Antenna Matching

Amplifiers usually give a system impedance of 50 ohms.

Visit this site to build a balun for your antenna:
http://www.odyseus.nildram.co.uk/

Look under RF microwave theory, Balun Design. This will given you max. power transfer and low return loss at the resonance frequency of the antenna.

Cheers,
Element7K


Vulcan said:
hey all....

how do i match an antenna to an amplifier output for maximum power transmition and low return loss ??

input signal is a video signal at 203MHz.

please ask for any missing parameter..

thanks !!
 

Vulcan

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thanks a lot...

i try and test what you suggested.

:)
 

Element7k

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Depending on your operating frequency, I will suggest the use of the 1/4wave sleeve balun. The ARRL Radio amateur handbook is a good source to learn how to make it if you have access to the book.

I will be able to attach the diagram and procedure here on request if you need it desperately.

Element7k
 

dragonlea

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203M?
is it a baseband signal or rf signal?
 

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