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Ron Hoffman

Ron's Articles

Build Your Own ECG-EKG Unit
February 2017
For parts costing less than $50, I built an ECG-EKG unit that plugs into my laptop computer’s microphone input jack.

Build a Sump-Fill Level Controller
December 2016
Need to monitor the high or low level of a fluid? Choose from these two versions of a sump/fill level monitor/controller.

Low Cost PC Two-Channel Oscilloscope
August 2016
Build an easily portable and cost-effective two-channel oscilloscope that hooks up to a PC.

Universal Oscillator Topologies and Applications
November 2015
Explore and analyze several circuits that you can use to make light dimmers, PWM motor speed controllers, model train controllers, heater controls, and a host of other applications.

Build a Personal Guitar Microphone Pre-Amp
November 2013
Fine-tune the sound for your guitar just the way you want it with this handy device that will also work with Karaoke machines, boom boxes, and surround sound systems.