Entries by JFW Eng Dept

What is the use of a fixed attenuator?

A fixed attenuator has two main uses:  decrease signal power level, improve poor VSWR.  A fixed attenuator is a passive device with internal resistors whose resistive values are calculated base on the impedance (50 Ohm or 75 Ohm) and the desired attenuation value.  The attenuation value is expressed in terms of decibel (dB).  When the […]

What is the difference between reactive and resistive power dividers?

Understanding the difference between reactive and resistive power dividers will help you create the best functionality for your RF testing setup.  Their functionality is similar but yet different. Resistive Power Dividers Their construction is a star configuration.  All ports are symmetrical.  There is no common port with resistive type design.  The star configurations functions as […]

What are the 3 types of electro-mechanical RF switches?

The goal of this application note is to differentiate the three different types of electro-mechanical RF switch types.  Each type has its own unique functionality and its own pros and cons.  Understanding their differences is key to getting the functionality you require.  There is a cost tradeoff for latching and failsafe/normally open functionality.  Mechanically latching […]

How do I choose a RF attenuator?

When choosing a RF attenuator, there are a couple of questions about how you will be using the attenuator that determine which attenuator type is best for your application. Does the attenuation need to be variable or can it be a single fixed value? For fixed dB value use a fixed attenuator. For variable attenuation, […]

What is a RF transfer switch?

A transfer switch is a unique type of RF switch.  Most RF switches have a single common port that switches between several ports i.e. 1P2T, 1P3T, 1P8T.  The transfer switch does not have a single common port.  Instead a transfer switch has 4 ports with two thru paths.  The thru paths can be vertical like […]

How do I choose a RF switch?

When choosing a RF switch, you must first determine which type of switch best suits your application.  There are electro-mechanical switches and solid-state switches.  Both types of switches perform the same function (i.e. route RF signals), but each have key differences in RF performance.  Below we list a description of each type of RF switch […]

How does a non-blocking matrix switch work?

A non-blocking matrix switch is constructed with power dividers and RF switches. The power dividers provide the functionality that make this design non-blocking. The power dividers fan-out the RF signal so that it is available for multiple simultaneous connections. If an input port is already connected to an output port, it is not blocked from […]

4X4 Blocking Matrix Switch | DC-26.5 GHz

Model 50MS-455 is an 4X4 blocking matrix switch.  All unused ports are absorptive (i.e. self-terminating into 50 Ohm).  It is available with 3.5mm female connectors.  The matrix is constructed using switches on both halves of the matrix.  Each input port can be set to only one output port at a time.  A 4X4 blocking matrix […]

How does a blocking matrix switch work?

Think of a blocking matrix switch as an assembly that is built with an “input port” half and an “output port” half. Whether you use RF switches or power dividers to build each half determines how the matrix switch distributes the signals through the matrix. For a blocking matrix switch both halves are constructed using […]