Design a 50 ohm impedance microstrip line for RF signals

For RF signal you must draw a 50 ohm net between chip and antenna to get the best performance.This post is the result of my web research on this topic …

There are two ways to design your emitter to antenna solution:

  • A microstrip line : basically you have a net on the top driving the signal and a ground plane on the PCB bottom

microstrip line

  • A coplanar wave guide : your signal is drive by a PCB net on top with two ground plane area on its left & right. If you also have a ground plane on the bottom it’s a grounded coplanar wave guide

The way to get a 50 ohm communication way is different depending on your choice.

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RFRPI – wiringPi delayMicrosecond problem with RPI 2+ and fix

I fixed tonight a problem with rfrpi and Raspberry 2+ ; it seems that wiringPi 2.25 have a bug with delayMicroseconds() function that works perfectly when less than 99us and do not work correctly with larger values.

Waiting for the fix the code have been updated to work correctly with RPI2+ ; so please if you are using the shield with RPI2+, update the rfrpi code from bitbucket.

RFRPI works certified with Raspberry PI 2+ for RF433

Raspberry Pi B+ - RFRPI Shield

Raspberry Pi B+ – RFRPI Shield

I’m proud to announce the compatibility of the RFRPI shield (RF433 transceiver for RPI) with the new Raspberry PI 2+

To get all detailed information about this shield you can read this post

You must use wiringPi >= 2.25 for RPI2+ compatibility.

RFRPI shield V1.2 released for RPI B+

Raspberry Pi B+ - RFRPI Shield

Raspberry Pi B+ – RFRPI Shield

I’m proud to announced the Raspberry PI shield for high quality RF433 have just been released to be compatible with Raspberry Pi model B+ (and A+).

The shield works exactly the same with the RFRPI lib. It is a little bit mode compact and modified to fit the usual cases.

You can contact me for orders.

Getting start with rfrpi card v1.0 – rf433 for raspberry pi

rfrpi_2RfRpi card is a RF433 emitter and receiver add-on of Raspberry Pi. This card is based on high quality receiver and transmitter I have selected after tests you can find here and here. This article describes how to get start with this shield.

To buy this shield the best way is to sent me a comment on this post, the price is 60€

The Shield is now working with Raspberry PI B+ and previous versions. The Shield is also working with Raspberry PI 2+. For these two last version you need to compile a kernel driver.


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Raspberry PI RF433 transmitter shield

A lot of you are coming to my blog for RF433 with Raspberry PI content (here). This article is a small part of a larger project I have. As part of this project I built a Raspberry Pi shield including an RF433 emitter and receiver. I could sell this shield to some of view if it make interest to you. To make it I selected emitters and receivers to get the best quality / price compromise.  (read my other articles on this topic) I could sell it around 60€ + port.

Update : chek this article for all informations on the shield and buy it !

RF433 shield for Raspberry PI

RF433 shield for Raspberry PI v0.1












My question to you is : would you be interested in a such thing ?

If yes : leave me a comment with your email address ( I’ll will remove this address before validating it )

RF433 Raspberry PI shield v1.0

RF433 Raspberry PI shield v1.0


Here is the Version 1.0 with antenna connector integrated to PCB.

Oregon Scientific sensors with Raspberry PI

After mixing different source of information, I was able to decode some Oregon Scientific sensors to get Temperature and Humidity indication, over the air, on 433.92MHz, with a Raspberry PI system. This article gives some details of this adventure …

You follow this implementation at your own risk…

If you are interrested in this article, you could also take a look here where you can find a RF433 shield and the associated code


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RF433 – different transmitters test

After having test some receiver, naturally, I’ve tested some transmitters, the objective is the same : get the best coverage in the same condition : I would say poor conditions. Lots of wires going every where and an antenna make with a simple 17.3cm wire. As expected, results vary regarding the emitter used. Reed more to get details.

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