SPECIAL ANNOUNCEMENT: We are happy to announce that Aircraft Tool Supply Company has acquired the entirety of Eastern Technology Corp's product line as of July 1, 2022. Our friends at Eastern Technology have decided to cease operations after over 50 years of providing outstanding products, and in so doing, they have given us the opportunity to carry forward their legacy of excellence. In carrying forward the Eastern Technology tradition, we we took the time to re-engineer their E50 Magneto Synchronizer and E5 Ignition Cable Tester flagship products to make them even better. Now, after many months of design, in house, and field testing, we are proud to introduce the new E5A, and E50A into the Aviation Field! We invite you to take advantage of our hassle-free 30 Day Money Back Guarantee and try it for yourself! If they don't meet your expectations, send it back and we'll refund your full purchase price with no questions asked.

The single biggest source of energy loss in an ignition system is from a defective harness. That is why it is absolutely essential that you validate your harness' ability effectively to deliver energy from the magneto to the spark plugs. Unfortunately, a multimeter cannot do that because although a harness may pass a simple continuity test, it may still fail in normal operation because, quite frankly, high-voltage behaves in very strange ways. It can jump to ground through microscopic flaws in the insulation and carry a good amount of the magneto's energy with it. It can also jump between cables and cause firing problems. Or it can jump to low voltage systems and cause radio noise or navigation problems. That's why it is essential that you check your ignition harness from time to time, and the E5A is the instrument you use to do it. 

The E5A works by taking advantage of the principle that electricity will always try to take the electrically shortest path to ground. Internally, the E5A has a spark-gap which is the shortest path to ground under normal conditions. So when you test a good cable, the high voltage pulses will be unable to leak to ground through a good cable and will thus have to jump the spark gap, producing a visible arc, which is your indication that the cable is in good shape. However, if you do not see the spark gap, it means that the pulses are leaking to ground through the cable, and that should be cause for concern. It's a simple but very effective test that will save you countless hours of frustration when diagnosing ignition problems.