I'd like to hook up a small raspberry pi project to my apartment's doorbell. I've taken the case off to take a look at the wiring and it looks pretty simple, but I have some questions about it; apart from some breadboard experiments I'm an complete newbie to electronics. [more inside]
posted by whir on Apr 4, 2013 - 5 answers

I've got some car parts I'm selling on eBay, and I need to hook them up to power in order to check a few things and make sure that they work. [more inside]
posted by iknowizbirfmark on Apr 3, 2013 - 12 answers

I can't quite get to the bottom of a USB peripheral auto-switching circuit diagram. [more inside]
posted by le morte de bea arthur on May 17, 2011 - 13 answers

How can I wire a bass so that the volume and tone knobs are bypassed? [more inside]
posted by ignignokt on Nov 13, 2010 - 5 answers

My son got a 130-in-1 electronics lab for his 8th birthday and discovered digital logic from MacCauley's How Things Work. Now he wants to build a half-adder. Help? [more inside]
posted by rikschell on Sep 13, 2010 - 15 answers

I have a friend who would like to learn the mechanics of building effects pedals for guitars. [more inside]
posted by kittyloop on Sep 9, 2010 - 9 answers

What is this device that I found inside of a Williams Grand Prix electromechanical pinball machine from approximately 1976? [more inside]
posted by mmcg on Nov 8, 2008 - 18 answers

Wiring/music equipment question: I have a fairly cheap 30WVox guitar amplifier with a phone/line out jack on the back. When I plug something into the jack, sounds stops coming from the amp's speaker and starts coming out of whatever I plugged in instead. However, I would like it if the sound would come out of both at the same time. How easy or difficult would it be to rewire the amp so that it works this way? I'm good with a soldering iron, but not too great with circuit analysis.
posted by donkeymon on Aug 30, 2008 - 4 answers

Help me diagnose repeated failure of my lighting dimmers. [more inside]
posted by jon1270 on Jun 26, 2008 - 20 answers

How can I use the speakers in my TV as the "center" speaker on my receiver? [more inside]
posted by odinsdream on Apr 7, 2008 - 11 answers

I've pulled an RF modulator out of an old VCR, but I don't know what some of the pins are for on the unit. Help me wire it up to modulate a composite video signal. [more inside]
posted by odinsdream on Feb 12, 2007 - 12 answers

I'd like to trigger a relay that momentarily closes a switch based on the voltage of another wire. Maybe. I think. Please help me with this basic (I hope) electronics project. [more inside]
posted by odinsdream on May 14, 2006 - 6 answers

I have an old Pair of Zenith Allegro speakers (50-watt, 8-ohm) with pre-attached cables and RCA-style plugs (male) for connecting to the stereo. I'd like to use them with a more modern receiver (50-watt max, 8-ohm) that accepts straight wire from the stereo; should I just lop off the ends and wire them in, or is there a better method? Also, can I use them with a >50-watt stereo if I keep the volume down, or is that just bad?
posted by The Michael The on Dec 17, 2003 - 2 answers