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The default serial speed on the ESP8266 WiFi chip is 115200 baud. If you connect this chip to an Arduino and want to use SoftSerial to talk to it, it will not work. The SoftSerial library is limited to 9600 baud because of hardware limitations of the Arduino. If you want to talk to the ESP8266 with an Arduino at lower …
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[caption id="attachment_2130" align="aligncenter" width="450"]WiFi Serial Transceiver Module Breakout Board w& ESP8266 pinout[/caption] This is the pinout for the Seeed WiFi ESP8266 breakout board. Please be careful, it only accepts 3.3 Volt nominal input voltage and logic. Putting 5 …
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If you used DSA keys to log in to your SSH server and have upgraded your client machine to macOS Sierra (or OSX Sierra if you like), you probably ran into this problem: [sourcecode language="text" gutter="false"] client$ ssh -p 8123 george@10.0.0.10 -i ~/.ssh/id_dsa Permission denied (publickey). …
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Many years ago, I used to do some radio fox hunting with cars. Usually these hunts are at night to make it more exciting, and can be great fun. As I got older I lost interest and moved on to other things. But last year, I decided to have a go at a popular balloon fox hunt on 144MHz. This is quite a large scale and …
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Ever wondered how well your 50Ω coaxial cable is working? If you have a reasonably fast oscilloscope, preferably up to 100MHz and a signal generator which can generate short bursts, you can measure not only the length of your cable, but also the return loss at a certain frequency. From that, we can learn the …
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In every Java project where I need to do strong cryptography, I run into these dreaded unreadable stacktraces which send you into the woods. After a long search I usually discover that the Unlimited Strength Java Cryptography Extensions are not installed. To prevent frustration of users of your software, you can simply …
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However I disagree with sites like Ashley Madison and the way its owners scam people, last week I have noticed something far more disturbing. As I understand, Ashley Madison was charging people for their profiles to be deleted, and then did not (promptly) delete them. I guess some of it's "hackers" got caught …
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If you are using JAXB in a maven/java project to unmarshal an XML document and you get: javax.xml.bind.UnmarshalException: unexpected element (uri:"urn:iso:std:somestuff:xsd:somestuff", local:"Document"). Expected elements are (none) Or if you are using JAXB to marshal an XML document and you get: …
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Undoubtedly the Baofeng UV-5Rx delivers a lot of radio for your buck. However some models in the range have a bad reputation for the transmitted audio sounding soft and muffled. In 2013, Remco PA3FYM obtained the schematics of the radio and devised a modification where transistor Q17 of the VOX is re-purposed as …
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When doing integration testing or fixing a bug in a piece of Java code that uses Oracle as a database, being able to do quick exports and imports of your schema can be a big help. Sometimes just calling Oracle's imp/exp commandline tools from your code can be of help, but I was looking for something a bit more portable …
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