3:1 microwave combiner - RF Cafe Forums

The original RF Cafe Forums were shut down in late 2012 due to maintenance issues - primarily having to spend time purging garbage posts from the board. At some point I might start the RF Cafe Forums again if the phpBB software gets better at filtering spam.

Below are the old forum threads, including responses to the original posts.

-- Amateur Radio
-- Anecdotes, Gripes & Humor
-- Antennas
-- CAE, CAD, & Software
-- Circuits & Components
-- Employment & Interviews

-- Miscellany
-- Swap Shop
-- Systems
-- Test & Measurement
-- Webmaster

Qorub
Post subject: 3:1 microwave combiner
Unread postPosted: Sun Apr 24, 2005 11:31 am

Hi everyone.
I want to know about 3:1 directional couper (combiner). Can anyone provide me papers, articles or circuits about it?
Thanks for your time and help.
Qorub

Qacer
Post subject: LNA (Low noise amplifier) using an NPN BJT with feeback
Unread postPosted: Sat Apr 23, 2005 2:18 pm
Offline
Captain

Joined: Sat Apr 23, 2005 2:09 pm
Posts: 17
Location: Tampa, FL
Hi all,

This is my first post, so please excuse my newbieness.

I'm reading up on LNA design, and I'm curious about the DC bias feedback setup using a reactive component (e.g. inductor) at the NPN's emitter lead to improve stability.

Can someone direct me to the formal analysis of this with regards to relating it to stability? I'm assuming that it helps maintain the collector current to have a uniform stability across a band of frequencies. I'm just not to sure how to come up with the reactive component value.

I can see the results right away using ADS, but I would like to see some sort of analysis on paper.

Thank you very much!

Posted 11/12/2012