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Setting up a CA SSL certificate in hMailServer

I’m a big fan of hMailServer, but the documentation for setting up SSL certificates and the certification chain is a bit lacking. The easiest way to check if hMailServer is setup correctly is to use OpenSSL. openssl.exe s_client…

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1,500,000,000 the Epochening

Don’t forget that at 2:40am, 14 July 2017 (UTC) the Linux epoch will hit 1,500,000,000 (1.5 Gigaseconds). Visit https://www.john.geek.nz/epoch to watch the excitement! It hit 1,000,000,000 back in September 2001 and it won’t hit 2,000,000,000 until May 2033.

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Modifying float voltage of a TP-SCPOE-1224

Adjusting the float voltage of a Tycon Systems TP-SCPOE-1224 The Tycon Systems TP-SCPOE-1224 is a Solar and Power over Ethernet powered DC UPS. You connect it up to a 12v battery, power it over ethernet, add an optional…

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Power meter optical pulse detection

I’ve always planned to monitor my electricity usage. I had previously (about a year ago!) ordered some power transformers from seeedstudio and a six channel ADC for simultaneous three phase current and voltage measurement but never got around…

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Wiring up the ESP8266

Before you can program the ESP8266, you need to wire it up. First things first, the ESP8266 uses a 2mm pin spacing so you can’t use a standard breadboard as these use a 0.1 inch spacing. It also…

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Introducing the ESP8266

About a year ago I put up some money for the Wino-Board kickstarter project, received my Wino-Boards and did nothing with them for 12 months. They are effectively a tiny Arduino board attached to the innards of an…

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EP Solar MPPT Tracer charge controller serial code

Following on from my previous post working out the EP Solar Tracer serial protocol, I’ve got code working on a Raspberry Pi. It’s even validating the CRC checksum.

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EP Solar MPPT Tracer charge controller serial interface

I’m currently involved in a project to set up a solar powered wireless station and wanted to remotely monitor the battery charge process. I looked into a number of charge controllers to see if any of them could…

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dump1090 binary built for Raspberry Pi / Arm

If you’re after a binary of dump1090 for the Raspberry Pi without having to build it, here’s a compiled binary for you. I built it on Arch linux, but it also works on Raspbian, or likely any other…

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Pulsecounter PCB’s have arrived

I posted recently about detecting power loss in an AVR and quickly writing values to EEPROM before power is lost completely and have since received the PCB’s I ordered from oshpark. This is the first time I have…

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