Measurer deviation frequency SK3-39
Also, this device may be referred to: SK3 39, SK339, SKЗ-39, SKЗ 39, SKЗ39, ck3-39, ck3 39, ck339.
SK3-39 measurer deviation frequency combines the functions of measuring the frequency deviation and the coefficient of amplitude modulation. The tool is based on the principle of a superheterodyne receiver with one frequency conversion to an intermediate frequency of 256 kHz.
Measurer deviation frequency SK3-39 is designed for:
- A forced frequency deviation measuring frequency modulated (FM) signal in a smooth range of carrier frequencies from 0.75 MHz to 50 MHz and a frequency of 0.465 MHz (doubler 5.408.015-01);
- A parasitic frequency deviation range in a smooth carrier frequencies from 0.75 MHz to 50 MHz and 0.128 MHz frequencies (doubler 5.408.015) 0,256 MHz (input IF) 0,465 MHz (doubler 5.408.15-01);
- Measuring the ratio of the amplitude modulation of the amplitude-modulated (AM) signals and undesired noise modulation and smooth range of carrier frequencies from 0.1 MHz to 50 MHz;
- Measurement of amplitude modulation factor, concomitant FM signal and a frequency deviation accompanying AM signal.
Measurement of AM is based on the method of two voltmeters: measurement of the average and peak values of AM signal.
Measurement of the frequency deviation is based on the transformation of the FM signal in AM-FM oscillation amplitude changes to the law, the law of proportional change in frequency of the input signal.
Specifications measurer deviation frequency:
The range of carrier frequencies in the FM mode:
- In the area from 0.75 MHz to 50 MHz - smooth;
- A portion of from 0.1 MHz to 0.75 MHz - fixed frequency of 0.128 MHz, 0.256 MHz, 0.465 MHz;
Carrier frequency range mode AM - 0.1 MHz to 50 MHz - smooth.
Overlapping range of carrier frequencies from 0.75 MHz to 50 MHz is provided on the subbands:
- 0.75 MHz to 1.5 MHz;
- From 1.5 MHz to 2.5 MHz;
- From 2.5 MHz to 5 MHz;
- From 5 MHz to 10 MHz;
- From 10 MHz to 20 MHz;
- From 20 MHz to 40 MHz;
- From 40 MHz to 60 MHz.
Error of frequency in megahertz in numeric scale marks - no more than ± (0,02 f c +0,005).
Stock range and the edges overlap between subbands - not less than (0,04 f c +0,01) MHz.
The minimum input signal level (sensitivity of the instrument) at an input resistance of 50 ohms at a range of carrier frequencies from 0.75 MHz to 50 MHz - no more than 50 mV.
Maximum input level - 2.5 V.
In the measurement of the frequency modulation measurer deviation frequency SK3-39 has the following parameters:
Measurement of the frequency deviation of 10 kHz to 0,001 kHz to the range from 0.75 MHz to 1.5 MHz, and from 30 kHz to 0,001 kHz to the range from 1.5 to 50 MHz is performed on scales of 1 Hz, 3 Hz, 10 Hz, 30 Hz, 100 Hz, 300 Hz and 1 Hz, 3 Hz, 10 Hz, 30 kHz.
The measurement is the peak frequency deviation of the "up" (+) and "down" (-) and root mean square (ck).
At frequencies of 0.128 MHz, 0.256 MHz, 0.465 MHz, provided the measurement of small parasitic frequency deviation:
at a frequency of 0.128 MHz - 0.003 kHz to 0.5 kHz (sa);
at a frequency of 0.256 MHz - 0.002 kHz to 1.0 kHz (sa);
at a frequency of 0.456 MHz - 0.005 kHz to 1.0 kHz (ck).
At a frequency of 0,465 Hz is also provided measurement peak frequency deviation of the "up" and "down" to 3 kHz.
Range meter baseband CK3-39 from 0.03 kHz to 10 kHz carrier frequency in the range from 0.75 MHz to 1.5 MHz, and from 0.03 kHz to 15 kHz in the carrier frequency range from 1.5 MHz to 50 MHz (by pressing the BAND switch 20 kHz).
Modulation frequency at a frequency of 0.465 MHz - 1 kHz.
To carry out noise measurements in FM mode by pressing buttons 0.2 and 0.3-0.4 kHz BAND switch includes a filter with a bandwidth of at least 3 dB 0.03-0.2 kHz and 0.3-3, 4 kHz.
Signal attenuation in the stopband filters:
- At a frequency of 0.4 kHz to filter 0.03-0.2 kHz - not less than 12 dB;
- At frequencies of 0.15 kHz and 7 kHz for 0.3-3.4 kHz filter - not less than 12 dB.
The transition rate of amplitude modulation in frequency:
- If F M is not greater than 1 kHz - no more than 2 Hz rate;
- F M at not more than 15 kHz when M is not more than 30% in the carrier frequency range from 1.5 MHz to 50 MHz - not more than 10 Hz rate.
Parameters in the measurement mode amplitude modulation:
Measurement of the amplitude modulation in the range of from 0.1% to 100% is carried out on scales of 0.3%, 1%, 3%, 10%, 30%, 100%.
Measured amplitude modulation factor "up" (+) and "down" (-).
In the range of carrier frequencies from 0.1 MHz to 1.5 MHz amplitude modulation factor measurement is performed on the input IF (batch input).
Modulating measurer deviation frequency SK3-39 - from 0.03 kHz to 15 kHz.
Intermediate frequency device measurer deviation frequency SK3-39 in working conditions - 256 ± 7 kHz.
Input impedance meter SK3-39 - 50 ± 15 ohms.
Samoprogreva time - 30 min.
Continuous operation time - 8 hours
Power consumption - 60 · A.
MTBF - at least 10,000 hours
Lifetime - 5 years.
Technical resource - 5000 hrs
Dimensions meters - 495x215x300 mm.
Device weight - 18.5 kg.
Operating conditions of devices measurers deviation frequency SK3-39:
Ambient temperature - from 278K to 313 K (+5 ° to +40 ° C).
Relative humidity at +30 ° C - up to 95%.
Pressure - 750 ± 30 mm Hg.
Mains voltage - 220 ± 4,4 V.
Photos: SK3-39 (CK3-39)