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Showing posts from February, 2012

"Additional log on information may be required." NOT ANYMORE!

NOTE: This method is not at all reliable. cron jobs work better than startup scripts. But it seems that the cron implementation in DD-WRT is broken. So I switched to using TP-LINK router which happily run the more sturdy OpenWRT. OpenWRT handles cron jobs very reliably, look at my newer blog post on how to configure a router running OpenWRT to login to your Reliance Broadband automatically - this new method using cron has proved to be quite successful for me.



---Introduction, skip this if you already know what you are here for


You reach home after a long day at office and are looking forward to catch up with friends on facebook. You weren't able to do so at office 'coz the internet there is terribly restricted and you have recently cancelled the 3G data plan on your cell phone. You turn on the WiFi router and wake up your laptop from sleep mode and this message pops up!! So the first webpage you are forced to visit is your Internet Service Provider's to login to your account…

Piezoelectric sensors and actuators

A Tutorial on various kind of Piezoelectric transducers from Open Music Labs:


http://www.openmusiclabs.com/learning/sensors/piezos/



MAX232 Reference

'Coz I keep forgetting the directions of the RS232 signals all the time.



Warts on a wall wart

This is what happens when you plug in a AC/DC adapter meant for mains input of 110VAC/60Hz (USA/Japan) into a 230VAC/50Hz (India). AC/DC adapter is a simple Stepdown Transformer > Bridge Rectifier > Capacitor type. You can see from the pictures that the windings on the primary side heated up and melted and shorted out. The heat also caused some insulation to melt and ooze out of the transformer. 












It seems the wall wart (colloquial for AC/DC Adapters) has grown warts of its own! Hemorrhoids even!!