Operating on the grid-dlp meter principle, the Model 944 Flyback Transformer, & Yoke Tester provides a short test that will reveal even one shorted turn in. any TV flyback transformer or yoke. As an open winding will produce the same indication as a perfect winding on the short test, a continuity test is also provided. The need for this instrument stems from the fact that even one or two shorted turns will absorb the energy normally developed in the magnetic field of a flyback transformer or yoke and make it defective. While this is a very common reason for flyback transformer failure, it has remained a difficult trouble to detect because the slight change of winding resistance due to a few shorted turns is entirely masked by the normal commerical tolerances on winding resistance (±20%). (Ohmmeter measurements are useful only when a winding is open or more than 20% of the turns are shorted.) As a result actually replacing the flyback transformer with a new one, has been the only reliable way of checking this part. Not only is this a very time-consuming and difficult job, but as a general servicing procedure it requires either stocking a full line of replacements or purchasing a flyback transformer or yoke for a particular receiver without being sure that the transformer or yoke you are replacing is defective and therefore the cause of the trouble. The Model 944 is not only expressly designed to deal with this problem completely arid effectively, but to provide maximum ease of operation. All readings are made on a large 4 1/2", 50 ua meter with three separate "GOOD-BAD" scales for flyback transformer, yoke, and continuity testing. In addition, separate calibration points are provided on the meter scalefor air core and iron core flybacks so that all types may be tested accurately with no extra operation required (such as inserting an iron core into an air core type flyback to boost the inductance). Entirely professional in both appearance and performance, yet extremely compact for easy portability, the Model 944 is a wise and necessary addition to any TV serviceman's equipment.