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0 2797

So we got our hands on a brand new Rohde and Schwarz oscilloscope; this is a quick first look around the features and a preview of the proper review which will follow soon!

We’ve also taken some photos of the oscilloscope in operation which are shown below and a quick look at the intensity gradient function on video, by special request from the eevblog forum!

Click here to see the photos

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0 2026

We’ve made it to the 4th video and in this video so moving on from our last video investigating variable frequency filters using analogue switches, we now go into more advanced variable filters using multipliers. As per usual we go through the theory and then show some results from some real circuits, as well as leaving you with some other options for making filters variable.
We also cover some common errors that are made when making filters variable and look at techniques to make the ranges covered larger, expanding to several decades of range.
For some examples covering the initial design of fixed frequency filters, see some of the earlier videos and in the next few videos, we’ll get the PCB assembled and take some measurements on a system which covers multiple decades, working towards a useful bit of lab equipment.

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0 2039

This is the third video in our filter design series and we’re finally looking at variable filters! We’re starting off with an overview of some basic techniques and then switched resistor techniques in detail, building up an example and measuring it’s performance.
To get started, you can use the spreadsheet that we’re covered in our previous video here to design it for the highest frequency, and then use the techniques covered here to make it variable.
In the next video we’ll cover some more advanced techniques for variable filters still moving towards a microcontroller controlled filter.

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0 2095

In this video we talk to Würth Elektronik, who make a vast array of passive components and some extremely interesting active components. One of the areas where Würth really stands out is the support and expertise that they provide.
We talk about inductors and filters, wireless power transfer and some of the transformers they offer.

The WE-FLEX transformer page is at the Würth site at, http://katalog.we-online.de/en/pbs/WE-FLEX

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0 1898

In this, our second tutorial video about filter design, we build on the topics that we covered in the last video. This time we take you through the steps to design a state variable filter of a fixed frequency. As a bonus, we also cover some of the nuances of prototyping precision analogue circuits.
The spreadsheet we talk about in the video can be found here, and should get you started with designing your own filters.
Following on from this in the next video we’ll start to investigate some of the techniques for making variable filters, controllable by a microcontroller or from analogue electronics.

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0 1978

This is the first in a few videos looking at analogue signal filters. We’ll be building up to designing filters controlled from a microcontroller, but firstly this covers some of the tools which’ll make designing filters easier, and go from basic RC filters to some high end active filters!

The books mentioned are available on Amazon below,

Active Filter Cookbook
IC Op-Amp Cookbook

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0 1874

In this video we spoke to LPRS at the recent Motiv8 Forums which took place at the Moller Centre in Cambridge.

LPRS are a supplier of short range radio modules and sensors, we had the opportunity to look at their new eRIC9 module and the eRIC development kit. These are licensed for Europe, America and have several antenna options available. All in all, really neat solutions for a design engineer!

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0 1920

This is the second part of our talk with Siretta who offer a wide range of RF solutions and modules, focused on machine to machine communications.

In this video we are looking more at the antennas, including some which are designed to cope with extremely challenging environments from everything ranging from asset management to agricultural.

Siretta talked about some of the solutions they offer, as well as talking about the custom solutions they can provide, working with the customer to ensure they get the right antenna for their problem.

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0 2043

This is the first part of our talk with Siretta who offer a wide range of RF solutions and modules, focused on machine to machine communications.

Siretta have vast experience with supplying modules and solutions which work with the commercial wireless networks to enable many different applications, such as data logging and monitoring of remote sites. Working with the commercial wireless networks, particularly for static applications can have many pitfalls and Siretta supply software, tools and complete solutions to make the wireless link almost invisible to the application over protocols including serial and ethernet.