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Author Archives: R-B

Atmega328 driven DIY Nixie clock

Posted on July 20, 2015 by R-B Leave a comment

Pete Mills’ has shared his cool-looking DIY Nixie clock design on his personal blog. His design is based on Atmega328 and uses software driven RTC and voltage booster to achieve ~175V DC for Nixie tubes.

DIY Nixie clock

Nixie tubes are cool. They have great aesthetic appeal with their difficult-to-photograph, warm orange glow, and dem curvy numerals. They add an organic je ne sais quoi to a hobby with ostensibly digital design cues. Further, they pose technical challenges in the way of producing and switching the ~175 V DC needed to light each tube element. And as far as I am aware, there are no new nixie tubes being produced; as such, procurement can be a challenge unto itself. My N.O.S. nixies came from Russia thru Ebay, and only 3 were duds. Incidentally the seller replaced those 3, FOC.

The strike thru text above results from a tip from +nicholasStock who points out new nixie tubes ae in fact being produced: http://www.daliborfarny.com/ The linked tubes are really impressive from a technical standpoint as well as asthetics. They seem to amplify all of the design cues we love about NOS nixies and the results speak for themselves. Might still be an issue with procurement, however…

IoT enabled soldering iron

Posted on July 19, 2015 by R-B Leave a comment

Vegard’s hacked his soldering iron and made it IoT enabled using NodeMCU, which is a ESP8266-based development platform. Now Vegard’s soldering station reports its set temperature to the Thingspeak server over WIFI.

IoT enabled soldering station

It also sends me Prowl messages on my Iphone when I forget to turn it off.

It all started when I needed to fix the display on the Soldering-iron itself after some guys at the soldering-iron factory forgot to mount the segment display properly.
The road to IoT is anything but streamlined yet. The NodeMCU & Arduino IDE integration is in it early stages and the tutorials out there are few and full of frustation.

Dual channel battery charger plus analyzer

Posted on July 19, 2015 by R-B Leave a comment

K.C. Lee‘s dual channel battery charger is a microcontroller-based efficient switching mode power supply design for not only the charging job but also for determining the charge/discharge characteristics of batteries.

Dual channel battery charger

It is a battery charger/analyzer. It is not going to save the world from an alien invasion or cure cancer or something equally noble. It is a nice tool for recycling or buying cheap batteries of unknown capacity/performance as it’ll let you test the discharge characteristics.

What set this charger design different are:

Flexible power source – two independent buck/boost converters allow higher/lower than input voltage. So you could be charging batteries from USB, vehicle power or green power source such as unregulated power from small solar power panel/wind power etc.
High switching frequency beyond traditional uC PWM type of design can offer. This allows for the use of much smaller components and also reduces input/output ripple current.
During discharge mode, the switch mode converter works to draw power away from the battery. The power can be diverted to external use. e.g. charging a Super capacitor bank, light. etc.
Scalable design for additional channels and/or higher power.

DeskPomo to improve productivity at work

Posted on July 17, 2015 by R-B One comment

DeskPomo is a time managing machine implementing the Pomodoro Technique to break down your work duration into intervals of ~25 minutes length, separated by short breaks, to improve the productivity.

DeskPomo time manager

The Pomodoro Technique is a time management method developed by Francesco Cirillo in the late 1980s. The technique uses a timer to break down work into intervals traditionally 25 minutes in length, separated by short breaks. These intervals are known as “pomodori”, the plural of the Italian word pomodoro for “tomato”. The method is based on the idea that frequent breaks can improve mental agility. —-copy from wikipedia.

As a maker, I’m really look high to the working productivity. Since that, I’ve been trying to use some time management app on my iphone. But after a period using I find out that the phone was just maked me distract all the time. I have been spent a large amount of time when facebook or twitter notification comes up which I don’t even notice. Finally, I‘ve decided to pick up my seeeduino and work out these little cute gadget which keep me focus on work.

Non-invasive power meter

Posted on July 11, 2015 by R-B One comment

Yonas Leguesse’s non-invasive power meter represents a much saver way of measuring electricity consumption without any direct wiring with the mains supply line. It uses a non-invasive current probe that is clamped around the mains power cable and a spark core module for periodic readings of the current sensor output and sending them to a webserver.