Offer stimulator (EAS) produces short pulses with an amplitude of up to 70V. Mode sedation served continuous pulses (switch position 4), and for excitation mode used 3 types of pulses. In position 1 are pulses period 2 p and a duty cycle 4. In position 2,3 of the output pulses with a period 2 PP., 3s. respectively (the meander). The diagram in Fig.1 consists of two generators collected on the chip D1 driver on chips D2,D3. Mixer on transistor Assembly NT. The voltage Converter is assembled on the transistors T1, T2, transformer on a ferrite ring and the rectifier diode VD6-VD9, filter C7, R7. The output is diode bridge VD1-VD4 and smoothing capacitors C4, C5 for normal operation of the measuring device.
Frequency generator fill is regulated by the resistor R2 is from 8 to 100 Hz. The frequency of the second generator varies discretely connecting the resistor R5. Resistor R9 is chosen so that at the maximum peak amplitude of the pulses at the output was sharp. R12 is selected by minimum current consumption from the power source. Resistor R8 regulate the amplitude of the output voltage, and therefore current, controlling the current measuring device. It is desirable to maintain current in the range of 10 to 20 A.
The printed circuit Board shown in Fig. 2.
For portable version (Hiking) the output bridge, a filter capacitor and measuring the device can be removed by taking the output directly from the capacitor C6. To earth the conclusion is attached metallic photographic tweezers for attachment to the fingers feet or hands. For camping options you can make with clothespins one metallized sponge or simply suitable piece of metal clamped in his fist.
The device showed astonishing vitality for almost 20 years operation.
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