Equipment and apparatus

A Portable Light-and-Sound Device for Signalling a Lifter's Call Time

U. K. Gadzhiev, Baku

English summary of Tyazhelaya Atletika. Ezhegodnik 1984 (Moscow: Fizkultura i Sport, 1984), pp. 69–70: the text is paraphrased, not translated; figures are the original images.

The competition rules allow a called lifter 2 or 3 minutes to prepare for an attempt. Timekeepers use either a simple hand stopwatch or a complex stationary electronic one, depending on the meet. Electronic timers cannot be introduced everywhere, being costly and demanding to install and run, and there is no need. The portable device described here makes the timekeeper's work easier, more objective and more informative than a plain stopwatch. It is simple and suits competitions up to all-Union rank.

When a lifter is called, the secretary or timekeeper presses the stopwatch button. After the set 1 or 2 minutes a warning sound is given and a white lamp lights; at the control time (2 or 3 minutes) the sound is repeated and a red lamp lights. A toggle switch (position 2 or 3) selects the mode. The stopwatch closes the circuit: one contact is its second hand, the other is soldered into the dial between the 57th and 60th seconds, so each full turn closes the contacts and a relay switches on the warnings. Any radio amateur can build it from the diagram.

Circuit diagram and photograph of the portable referee's signalling device with white and red lamps
Fig. 1. Circuit diagram and appearance of the portable device (white lamp on the left, red on the right). Relays R1–R6, 16 V; diodes D1–D4, D226B; capacitors C1–C3, 10,000×25 V, C4 and C5, 0.1, C6 and C7, 0.01; transistors T1 and T2, MP42B, T3, P213; resistors R1, 3 kohm, R2, 2 kohm, R3 and R6, 2.2 kohm, R4 and R5, 30 kohm; lamps L1 and L2, 6 V.