Captain Herrmano’s Mystery Box – a Reverse Geocache

Captain Herrmano's Mystery Box
Today we’ll be talking about Captain Herrmano’s Mystery Box, a piece of hardware that I built over a year ago. But what is this box, what does it do, who was it built for and who is this Captain Herrmano anyway? This will be the topic of this article.
What is Captain Herrmano’s Mystery Box?
The box is a so-called “reverse geocaching puzzle”. The inspiration for this project was a reverse geocaching box built in 2009 by Mikael Hart. Unlike Mikael’s version of the box, it’s not enough to simply find and visit the target place. To unlock the treasure of Captain Herrmano, the player has to solve more tasks.
The special thing about this box is that it interacts with the player, and not just via text – it also has sound and light feedback, as well […]

How to build a clap switch using Arduino

Arduino KlatschschalterToday, there is again a small Arduino craft project. This time, following the motto: “Soon it will clap, but no applause!” Because when you’ve finished reading the article and clap your hands, then your lamps should switch on and off.
The project originated from the (presumably nerd-specific) “emergency”, in which I found myself for some time and which looked like this: You want to go into the bed at night, but firstly you must turn on the light of the bedroom to be able to find the switch of the bedside lamp. Then you switched on the bedside lamp and run to the bedroom’s door again to turn off the bedroom light. You already notice the bedroom light is really just a means to an end.
As a clever computer scientists and hobbyists, one feels as though their relentless drive to […]

RadioduinoWRT – a do it yourself webradio

RadioduinoWRTToday I want to present you one of my larger craft projects. This time it is not just about software, but also about the associated hardware. What is it? A web radio!
I like to listen to internet radio stations, but I didn’t want to run my pc only for listening to webradios.  Connecting my phone to my stereo either wasn’t a solution, since I’d rather wear this with me, because I don’t want to run for each SMS / Whatsapp message to the music system. And because I always like to tinker, it was obvious to build a web radio as a standalone device myself.
As this article has become a bit longer, there is a brief overview of the following sections of the article, so that everyone can quickly find what he looks for.

What is the RadioduinoWRT?
Considerations before building
What should […]

How to increase storage on TP-Link WR703N with ExtRoot

tp-link wr703n with thumbdriveA few days ago I wrote about how you can flash OpenWRT on the TP-Link WR703N router and build a ~20$ cheap OpenWrt router this way. OpenWrt actually works quite well on the WR703N, but in retrospect the following problem arises.
Unfortunately the WR703N has only 4MB flash (memory), so (depending on the selected image/firmware) after installing OpenWrt there will be just about 900 kB of free memory available. If you now want to install one or more extensions for OpenWrt, which in my opinion is one of the main benefits of using a OpenWrt system, you will be confronted with “no space available” messages in really no time. One solution to “bypass” this problem is to “ExtRoot” your router.
ExtRoot is a functionality that can be used to outsource the OpenWrt file system of the router […]

How to build a 20$ low-cost OpenWrt router – Flash OpenWrt to TP-Link WR703N

TP-Link WR703NFor one of my projects I was looking for a router that runs OpenWrt. But the all time classic of these type of routers, the Lynksys WRT54GL, is definitely too expensive in my opinion and so I searched a for a cheaper alternative. And I found it.
The TP-Link WR703N is a really small router, which can be powered by USB and also can be flashed with OpenWrt.
An unbeatable argument for the TP-Link is in my opinion the price. So I think you will rarely find a new OpenWRT compatible router for less than $20. I bought mine on eBay for ~22$ including shipping, but at the moment the US prices are a little bit lower. I also added some pictures from the unboxing at the end of this blog post.
Where can I buy the TP-Link WR703N?

21,00$ at eBay […]