Circuit to use old phones as intercoms
Here’s a good post from 1993 on making a circuit to use old phones as inter-comms- Talking over the phones is easy. You put DC current through the phone and it transmits and receives audio. So two phones and a current source (about 25mA) all in series will give you a talking circuit. A suitable current source can be as simple as a 9V battery and a series resistor whose value is adjusted (with both phones offhook) till about 25mA flows. Link.
9 months ago Firefox 1.0 came out, 80 million downloads later, it’s hard for me to use anything else. I have a pretty tweaked set up, the G5 optimized build, the brushed metal theme and here are my
Max did a great guide on converting a cpu cooler into a graphics card cooler. Produced better results than expensive graphics coolers even though its lighter and cheaper. Test results available. [
This experiment uses a custom XSLT to convert GeoURL’s site-specific “near” information in RSS format to create a Google Earth KML file. You can create a static list (a snapshot based on the current sites indexed by GeoURL) or a Google Earth network link, which can be refreshed from within the application to get an up-to-date listing.
Here’s a modified tunecast 2 that now uses USB and PS/2 power instead of AAA batteries. This is part of an
Duke University students are building and will live in a 4,500-square-foot “SMART” house. The purpose of the experimental project is to continuously invent and test home tech. For example, humming a tune will turn on the stereo and play the song you were humming. Alarm clocks initiate the process of breakfast being cooked by machines. [
