2022.02.22: H-bridge deadband sequencer

2022-02-22 21:35 by Ian

This is a logic-level front-end to an H-bridge that provides deadband enforcement. This particular circuit supports 4-channels; sufficient for two H-bridges.


Crosspoint Audio Router with Volume Control

2014-05-27 08:35 by Ian

I've been needing this part for a long time now. So I've finally gotten around to doing the design work and making a production-worthy module.


Hand Replacement of large non-BGA surface-mount IC's

2009-07-05 12:12 by Ian

This is another procedure I wrote while doing camera repair. Occasionally, there was an identifiable chip that would go bad, but which replacement was considered impossible at our small shop. The alternative was replacing the entire PCB that it was mounted on, which would be an order of magnitude more expensive.



The Laser Microphone

2009-05-16 00:14 by Ian

Here is yet another un-intentionally wonderful product of the Cold War. This device is designed to detect slight disturbances in the reflection of a laser beam and convert them into sound. Very nifty to use!


A capacitance meter built from discrete ICs

2009-05-15 23:58 by Ian

Not much to say about this one. It was a project that I saw in an issue of Popular Electronics before it became Poptronics. It is a capacitance meter built from discrete ICs. It creates an RC oscillator and counts the number of wave-fronts over a given period of time to arrive at a value for the unknown capacitance.