Friday, February 20, 2009

Where to source tools and components in Austria

This is a short list of online stores i like. I live in Austria, but most of them ship to everywhere in the EU. Some sites may be available in german only.

CSD Electronics - Very good prices e.g. on some Atmel Microcontrollers
DealExtreme - Chinese online shop, wide range of cheap, but also quality stuff
- RC parts & models, brushless motors, ESCs, Accus, etc. Great CA glue!
Distrelec - comparatively cheap for low volume orders. fast delivery
Conrad - expensive. high quality tools, lots of odd components - computer parts - linear guides, acme thread rods + nuts
e-MadeinCHN - cheap RF modules, worldwide shipping

Surplus Stores
Pollin Elektronik - very cheap, tons of great stuff; shipment can take weeks
Neuhold Elektronik

Also, there are long and comprehensive lists of part sources at and


Hacking a digital alarm clock

First of all, this particular hack i did a few weeks ago to make my alarm clock enable external circuits is similar to this one that was featured on hackaday. If you think about building one of them yourself i recommend the other one - it's just a bit more expensive, but much more versatile.

Both basically work the same way: The speaker/buzzer driver of the mobile phone/alarm clock is used to trigger a thyistor. I just used TO92 general purpose transistors i had lying around.
Depending on what kind of signal source you intend to use, you should be able to omit the diode and maybe the capacitors if the resistors are small enough.
Anyway, it's best not to build a discrete thyristor like i did but use a "real" one.
Note that the thyristor will remain latched until you remove the load (e.g. using a switch).