ANALOGUE TACHOMETER • A budget-price analogue optical tachometer, specifically designed
Page 113
If you've noticed an error in this article please click here to report it so we can fix it.
for applications requiring continuously variable analogue indication of speed, without contact, and at low cost, has been introduced by Graham and White.
The M540 uses the wellproven single-lens reflex system which, with a single reflective mark and a visible light beam, makes it easy to use. Operating up to a metre from the target, direct speed readings to 6,000 rpm are given, to an accuracy of ±2%. Power is derived from AA alkaline batteries for long life.
The M540 is suitable for measuring speeds with an unstable hunting action, or if a "trend" is to be monitored, where digital instruments are unsatisfactory.
Graham White Instruments Ltd 135 IIatfield Road St Albans Hertfordshire AL1 4LZ