This site is devoted to practical and instructive electronics projects with an emphasis on amateur radio, makers, microcontrollers, and power supplies.

Several projects are based on the Arduino UNO and the ESP8266. Most projects are adapted to stripboard layout that provides very rapid prototyping at very low cost. The Arduino Nano format is a great, low-cost version of the UNO that works well with solderless prototype boards and stripboards. Likewise, the Wemos D1 Mini is a compact format suitable for embedding or stacking with shields.

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New Bethany version firmware for Weather Stations

July 11, 2017 It has been gratifying to hear from the weather station builders. I took a break from hardware development while on a beach vacation in June but made some important firmware upgrades between taking the sun and eating blue crabs. A few of the changes improve the reliability of the solar power supply, …

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Solar Radiation Shield under test

The D1M & D1S solar powered weather stations heat up in direct sunlight giving an incorrectly high-temperature reading. Early results from testing an Acurite solar radiation shield are very good. The shield is available from several online vendors although it appears to be out of stock until August 14, 2017. Check around for a good …

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Temporary Weather Station at the beach thru June 26, 2017

I’ve temporarily set up one of the IoT Kits weather stations in Bethany Beach, Delaware while here on vacation for the next week and a half. Follow it at: https://thingspeak.com/channels/286120 and http://aprs.fi/w4krl-8 73 Karl W4KRL

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Important Weather Kit Update 16 June 2017

IMPORTANT NOTE FOR WEATHER STATION BUILDERS Some builders have noted that the markings on the XH 2-pin connector leads do not conform to the instructions.  It appears that every pair has a different set of markings. Getting the polarity of the connectors wrong, particularly for the LiPo cell connector, can damage the TP4056 charger and D1 Mini …

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Power supply measurements

Most electronic projects operate on low voltage direct current. This is often provided by a USB connection or a battery. There are several possibilities to power a project from the 120 Vac power line. A common way is to use a wall adapter (wall wart) and feed low voltage direct current to your project through a …

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