question about balun? - RF Cafe Forums

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Tiany

Post subject: question about balun? Posted: Sat Sep 12, 2009 10:39 pm

Lieutenant

Joined: Sun Jun 07, 2009 9:14 am

Posts: 4

1.Who know the balun(T2&T3) in following picture is

1:4 or 1:9?

2.If the balun(T2&T3) is 1:4,then what is the different between this balun and another balun(T4&T5) as following picture.

.

Thanks.

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Jose Arrina

Post subject: Re: question about balun?Posted: Wed Sep 16, 2009 12:18 pm

Lieutenant

Joined: Thu Mar 30, 2006 9:01 am

Posts: 4

Hi Tiany:

Based on the cascode transistor configuration, I'd say those are coaxial implementations of 3dB hybrid couplers for the input and output. Length differences for input/output are for bandwidth/tuning purposes.

Sound reasonable?

_________________

... Jose' Arrina

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Tiany

Post subject: Re: question about balun?Posted: Thu Sep 17, 2009 8:09 am

Lieutenant

Joined: Sun Jun 07, 2009 9:14 am

Posts: 4

Thank Jose Arrina.

Do you know the impedance transform of the balun is 1:4 or 1:9?

Posted  11/12/2012