Introduction

OTARI MX-5050 BII and MX-5050 MkIII-2

Speed Calibration, Head Alignments and Audio Record and Reproduce Alignments

1.0 INTRODUCTION↑ TOP

These instructions contain the procedures for Head Zenith, Wrap, and Azimuth adjustment, Speed Calibration, and Audio Record and Reproduce Alignment on the MX-5050 BII and MkIII-2 Series Tape Recorders. Speed Calibration and Audio Record/Reproduce procedures are performed at 7-1/2 and 15 ips with NAB equalization at 250 nWb/m reference fluxivity, biased for Ampex 456 tape.

1.1 TOOLS AND EQUIPMENT REQUIRED↑ TOP

• AC Millivolt meter calibrated in dB, capable of measurement to +16 dBm
• Audio Oscillator - manually sweepable from 20 Hz to 20 kHz, capable of +16 dBm output into 600 Ohm load
• Dual Trace Oscilloscope with X-Y inputs
• Frequency Counter with 1 Hz resolution
• 15 ips Reproduce Alignment Tape - MRL Catalog # 21J205
• 7.5 ips Reproduce Alignment Tape - MRL Catalog # 21T204 (This tape is necessary only if aligning at 7.5 ips)
• 7.5 ips 3150 Hz Speed and Flutter Test Tape - MRL Catalog #231-570-480-110
• 7.5 ips 500 Hz to 20 kHz Fast Sweep Tape (1/4" MRL Cat # 23T136; 1/2" MRL Cat # 33T139)
• Hand-Held Demagnetizer (Han-D-Mag by R. B. Annis Co. is recommended)
• Isopropyl Alcohol - 70% pure or greater (Do Not use Rubbing Alcohol)
• Cotton Swabs
• 10.5" Reel of 1/4" Ampex 456 Tape (virgin tape)
• Reel of used recording tape which can be discarded after use
• High Intensity Lamp
• Small white card approximately business card size
• OTARI Head Inker or dry erase marker
• Insulated alignment tool
• #2 Vessel Screw Driver (OTARI P/N ZA-53A)
• 3mm and 4mm Hex Keys (OTARI P/N ZA-51C)

NOTE: MRL Reproduce Alignment Tapes are available from

Magnetic Reference Labs
229 Polaris Suite 4
Mt. View, CA 94043
(415)965-8190