Whistler: Electronic Trainer/Coach Schematic Circuit Diagram
This device makes it possible to generate beeps at chosen regular time intervals for timing track race training. Each time interval is indicated by a beep, and the end of a performance test is indicated by a double beep. Two types of test are allowed:
Tests 1–4 offer a certain number of cycles, each comprising two periods, a running period followed by a rest period. For example, test 1 offers six cycles comprising a 15 s running period followed by a 15 s rest period.
The first three tests have preset values, while test 4 is fully adjustable. Test 5 lets you determine Maximum Aerobic Speed (MAS) by making the athlete run in 2 min blocks at increasing speeds. Lengths are run between markers that are either 20 m or 25 m apart, according to choice. You can choose the initial speed and maximum speed values for the test. After 2 min, the speed increases by 1 km/h. In a constant two minute period, the number of lengths run in a shorter time increases. The MAS represents the highest speed the athlete reaches without letting up.
The circuit is very simple and just consists of a microcontroller, five buttons, a 2-line × 16-character display, an LED, and a sounder. A quartz crystal is required in order to obtain a sufficiently accurate timebase.
At power on, the system is stopped. Pressing the Run/Pause button turns the system on and the LED lights. Pressing the same button again puts the system into Pause mode. A training session can be restarted without losing the current values. On the other hand, a final stop (by pressing Escape) resets the values for the training underway.
The software (BASIC source and HEX file), the pre-programmed microcontroller, and the detailed, copiously-illustrated manual (in French only!) are available from [1].
Internet links
[1] www.elektor.com/100203