MIL-PRF-49164C(CR)
Where: k1= 0.95, for 5 percent below average gain; or 0.9, for 10 percent below
average gain.
k2 = 1.05, for 5 percent above average gain; or 1.10 for 10 percent above average gain.
AI,T = voltage gain of channel I at temperature T
AT = average gain of 20 channels at temperature T
AT= 25°C = average gain 20 channels at temperature T = 25°C
Note: Brackets = room temperature normalization factor.
4.5.2 Gain tracking error. Channel-to-channel gain control tracking shall be tested using
the postamplifier with an auxiliary control module (see 6.2.i) with both modules placed together
in a temperature chamber. Voltage gain shall be measured per 3.5.3. At zero (0) dB, the gain of
each channel shall be normalized using the following equation:
Normalized gain = [AI,T(at 0 dB)]/[AT(at 0 dB)]
Where: AI,T= voltage gain of channel I at temperature T
AT = average gain of 20 channels at temperature T
When the gain has been decreased 30 dB, the following equation shall be used to
determine gain tracking error.
(k1) · AI,T [(at 0 dB)/AT(at 0 dB)] ≤ AI,T[(at 30 dB)/AT(at 30 dB]≤ (k2) · AI,T[(at 0 dB)/
AT(at 0 dB)]
Where k1= 0.95, for 5 percent below average gain: or 0.9., for 10 percent below average
gain.
(k2)= 1.05 for 5 percent above average gain: or 1.10 for 10 percent above average gain.
4.5.3 Verify voltage gain. Voltage gain shall be measured using a signal generator and
oscilloscope or RMS voltmeter. The output load shall be 470 ohms. With a measured voltage
input ein of 30 microvolts (V) rms and the signal generator set at the postamplifier midband
frequency of 1 kHz, the amplifier rms voltage output eout shall be measured. The midband gain
of the amplifier shall be:
eout
AV = ein
where:
ein = rms input voltage
11
For Parts Inquires call Parts Hangar, Inc (727) 493-0744
© Copyright 2015 Integrated Publishing, Inc.
A Service Disabled Veteran Owned Small Business