Manual for Mastech MY-64 Multimeter. View and download the pdf, find answers to frequently asked questions and read feedback from users. MANUAL. CAUTION: * Before attempting to insert transistors capacitor thermocouple for testing, always be sure that test lest leads have been disconnected From the owners manual and the Specification Sheet: • For polarity, positive current flows into the red lead and back out of the black Common lead. MASTECH®. CONTENTS. Frequency Measurement. (only for MY63 MY64) 14. Temperature(only for MY62 MY64) 15. Transistor Gain …….. 15. Specifications .Manuals and User Guides for Mastech MY-64. We have 3 Mastech MY-64 manuals available for free PDF download: Operator's Manual, Manual · 10. 1 Safety Information.