Posted by Mike on April 18, 2013
There is a degree of uncertainty at the moment regarding the future availability of HopeRF’s RFM22B and RFM23B modules. Having been in touch with a number of HopeRF’s European distributors the message appears to be that while they are indeed “not recommended for new designs”, there has been no end-of-life notification for either of these products. [...]
Posted by Mike on March 11, 2013
I finally found the time to make some measurements on the printed antenna used on my sensor board, which I didn’t think was performing very well. Turns out I was right. For this first part of the test various antenna configurations were tested by mounting them on unpopulated sensor boards connected to an Anritsu Sitemaster [...]
Posted by Mike on February 20, 2013
Over the last few weeks I have been helping out the guys over at OpenTRV with an implementation of the FHT protocol for use with HopeRF RFM22B and RFM23B modules. My as-yet unreleased sensor modules (as seen in another post) make use of an RFM23B, and I have an interest in evaluating the Conrad/ELV FHT8V [...]
Posted by Mike on February 11, 2013
I’m going to start by admitting that this isn’t going to be a tirade of abuse against the oddly named 802.15.4-based wireless tech, but rather a request for comments on an open, lightweight alternative, particularly for low-cost sub-GHz applications. I know what the point of ZigBee is, and the ability to form into self-organising mesh [...]
Posted by Mike on November 20, 2012
As part of my project to bring our central heating into the 21st century I have been working on a custom wireless sensor platform. My key aim here is to develop a low-cost, open solution with security designed in from the start; something that a lot of sub-GHz protocols seem to totally omit. I’m avoiding [...]
Posted by Mike on October 16, 2012
A simple example of a custom Gnuradio block for decoding a proprietary sub-GHz radio protocol.