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Wifi Connected LED Clock / MQTT Display

Wifi Connected LED Clock / MQTT Display

Also shared on Github For some time, I wanted to buy several digital clocks with the following attributes Wouldn’t require setting time manually – NOT HAVING THIS ABILITY THIS IS THE DEALBREAKER !!! – IT MUST fetch time from an NTP server and set the internal clock accordingly and will sync with the NTP server periodically. Would need to be plugged in to main power (USB), and it must be able to run for several hours with a rechargeable battery in case the main power gets off. Daylight saving time changes should be handled automatically (Twice a year) It should display custom messages pushed through MQTT (Weather or other alerts) It should display a message if the network connectivity is gone or if the NTP server is not accessible. In…
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Free Text based TV-DVR using a TV Tuner Box and a Linux Storage Client

Free Text based TV-DVR using a TV Tuner Box and a Linux Storage Client

I got my hands on a great TV Tuner/Streaming Box called HDHomeRun (by Siliocndust) and this device captures the over-the-air TV signals through a normal antenna and starts a streaming service on the local home network. I used to have small indoor antennas attached to each of my TVs at home and the over the air (OTA) TV broadcast signals captured by these indoor antennas were not that good. I wanted to have a powerful UHF/VHF antenna in my attic, but having all the TVs at home using that same antenna was a challenge. The HDHomeRun device solved this issue for me as I could connect that antenna to the HDHomeRun box and the streaming service it starts could be accessed and viewed by the Roku devices and TV apps.…
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Build an electronic workbench power supply using an old PC power unit

Build an electronic workbench power supply using an old PC power unit

Publishing a post after a while since I was busy with my work and some projects that were going on last few months, Anyway for some time I had an old mini form factor PC supply lying around and decided to make some use out of it by converting it to an electronic workbench power supply. The power supply was from an old Small Form Factor Dell Optiplex 390 and the first thing I did was open it up, cutoff the plastic connecters at the ends and sort the wire strands according to their color. The small gauge yellow, orange and red wired were also sorted with the normal gauge wires. Black                : 0V Orange            : +3.3V Red                  : +5V Yellow             : +12V Blue                 : -12V (at low amperage)…
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Water Softener Salt Level Checker (Using – NodeMCU/HomeAssistant)

Water Softener Salt Level Checker (Using – NodeMCU/HomeAssistant)

I frequently forget to put salt in my water softener and as an IoT solution I sometime back came up with a small circuit that would let me check the Salt level remotely on my laptop or mobile, and push Email/SMS Alerts when the salt level gets down below a certain level. For the setup I’m uisng a NodeMCU module (Any ESP8266 board would work), an Ultrasonic distance sensor, and my Home Assistant installation. The NodeMCU will be programmed using ESPHome. The Ultrasonic Sensor Used here is HC-SR04 NodeMCU board Here I’m measuring the distance from top of the bin to the salt surface level and getting the height of salt by subtracting that measurement from the total bin height. Salt Height = Total Bin Height – Distance from Top…
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Monitor UPSs with Nagios uisng Custom Nagios Plugins

Monitor UPSs with Nagios uisng Custom Nagios Plugins

I have a couple of CyberPwoer UPSs and to monitor them through Nagios I’ve been uisng some custom Nagios plugins I’ve written sometime back. CyberPower UPSs can be monitored uisng the pwrstat utility uisng their PowerPanel software but it will not work with other UPS brands. I have one UPS connected to host running Debian so the pwrstat command can be used for that. But I have another UPS which needs t be monitored through a Raspberry Pi (above pic) which is near it and unfortunately the CyberPowers’s PowerPanel  doesn’t support ARM bases systems yet (as of today). Therefore, I’m uisng the Network UPS Tools (NUT) and monitoring that second UPS uisng the nut-server. If your UPS is not CyberPower you can check if your UPS supports the NUT utility…
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Controlling a Tasmota Smart Outlet (with Power Monitoring) According to the Power Usage

Controlling a Tasmota Smart Outlet (with Power Monitoring) According to the Power Usage

After my last post on processing the RF Signals using nodered, I wanted to write on some more MQTT processing functions that I use in my home. I have several Sonoff S31 (Power Monitoring) Smart plugs that I have flashed with Tasmota firmware and connected to the Home Assistant. One of these plugs is connected to a power strip that I use as a charging station in my basement. My 18650-battery charger, the 20V BLACK+DECKER tool battery charger, 1S/2S/3S Lipo battery (that goes in my Hobby RC cars) charger and the usual 9V or AAA, AA rechargeable battery charger get their power through this plug. There’s another one of these Tasmotized S31 plug that provides power to the charger of the Polaris Kids ATV that’s in my garage.   It’s…
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Processing signals from 433MHz RF Devices to automate a Smart Home using MQTT/Nodered

Processing signals from 433MHz RF Devices to automate a Smart Home using MQTT/Nodered

I have been using a Sonoff RF bridge in my network to connect the 433MHz RF devices I have with the home network. In fact, there are two of these in my home to provide better coverage for the 433MHz devices. I flashed the Sonoff RF bridge with Tasmota firmware rather than using the factory firmware that came with it, so I don’t have to use the eWeLink app. After getting Tasmota, it it’s all in my control and I use MQTT and Nodered to process the RF signals and issue commands to other Smart Home devices (or other RF devices) to get things done. There are some great tutorials (one here) on how to get Tasmota on the Sonoff RF bridge, so I will not cover flashing Tasmota in…
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Monitoring ESPhome nodes with Nagios (using MQTT/node-red as the middleman)

Monitoring ESPhome nodes with Nagios (using MQTT/node-red as the middleman)

I have a HomeAssiatnt (Hass.io to be specific) instance running as a VM in my network and there are some ESPHome devices (ESP8266s) scattered around the house doing various measurements and pushing data to Home Assistant. All my ESPHome nodes have MQTT configured and they have static IPs. I also have a Nagios server (another VM – planning to move this into a docker container soon!) that monitors my home network and whether the network nodes are up and running. How do I make sure all my ESPHome nodes are up and running and generate an alert if any of those go down or unresponsive? As far as I found out, ESPHome devices are not  usually the best when it comes to responding to ping requests. So using a “binary_sensor:…
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