Measuring interference P4-12A (P-4-12A, P 4-12A)
P4-12A meter - a device designed to measure and find interference and measuring the high-frequency voltage at the output terminals of the source of interference and intensity of high-frequency fields, for which the instrument given a whip antenna with 1m (AA = 0.5 m).
- From 10 mV to 30 000mkV in the frequency range from 0.15 MHz to 12.5 MHz;
- From 30 to 100 mV 000mkV frequency range from 12.5 MHz to 30MHz.
The bandwidth of 9 kHz.
Power supply 12V battery.
Meter P4-12A is a high Microvoltmeter measuring the voltage in a narrow band of frequencies. Like any sensitive voltmeter, P4-12A has:
- Voltage divider;
- Detector with dial gauge.
For high gain in a narrow and unchanged by the restructuring of the frequency band used superheterodyne circuit gain, ie gain with frequency conversion. Thus, measuring P4-12A radios are calibrated with the gain and bandwidth.
Meters P4-12A is connected alternately to each resistor R and measure these stresses. Voltage noise is considered the largest in size of all the measured voltage.
Specifications meters P4-12A
- Instrument error is not more than 9%;
- Sensitivity - 250 mV / m
The entire range of frequencies from 0.15 to 30 MHz is covered by six sub-bands, which are used to switch the rotary switch ("Meas."). Restructuring within each band is made variable capacitor ("Setup").