Ortofon SB-2 Stroboscope Speed Checker

How to use the SB-2 Stroboscope:

Simply place the stroboscope disc on your turntable, turn on the motor and fine tune the speed whilst shining the stroboscopes light onto the stroboscope disc for an indication of when the speed is correct.
Three rings with line markings on the stroboscope disc are for fine tuning respectively 33 rpm, 45 rpm and 78 rpm. When the line marking is steady and does not move then the speed is correct.
* If the stroboscope disc is used together with a stroboscope flashing at 50Hz, then use the dotted markings as a reference.

Specifications:

• Dimension – 67 mm (W) x 68 mm (L) x 22 mm (H)
• Weight – 130g (with battery)
• Disc dimension – 100 mm (dia) x 1.0 mm (t)
• Disc material – Stainless steel
• Revolutions synchronised – 78 rpm, 45 rpm, 33-1/3rpm
• Housing material – Aluminum extrusion
• Battery – 2 x 1.5V (UM4)
• Accuracy of oscillation circuitry – 1/100 Hz , (0.1%)