In Case You Missed It
Aero ‘lectrics
Jim Weir presses the venerable LM317 variable voltage regulator (plus a few other parts) into service as a way to juice up a discharged battery.
Firewall Forward: New, Used, Something Else?
For some builders, new aircraft engines may just be out of reach. Dave Prizio explains what to look for in a used Lycoming or Lycoming-type engine along with what you need to consider before buying.
Aero ‘lectrics
Vibration is not good for engines, airframes or instruments. Jim Weir explains how to fashion vibration analysis equipment for less than retail cost.
