G BY FREE FALL APPARATUS

Consists of two units, each mounted on a plastic base which can be clamped to a 12 mm diam. retort stand rod. The solenoid unit ensures prompt release of a metal sphere on de-energising. The gate switch unit comprises a hinged steel plate held against an adjustable contact by a small magnet so that by proper adjustment, the plate falls promptly as soon as the falling sphere falls on it. Complete with stand.