TM 11-5820-801-30
Figure 2-9. Temperature Monitor Card 1A1 (Sheet 2 of 2).
c. Vacuum Measurement Circuit. The vacuum
subassemblies.
(pressure) is sampled in Module 2A3 by means of
2-16.
Second Stage Amplifier Circuits
measurement circuit is contained within VACUUM meter
(1) The second stage of the parametric
1M2 and 2A3J2. Interconnection of 2A3J2 and 1M2 is
amplifier (Module 2A2) consists of an RF circuit that is
accomplished on terminal board 1E1 at terminals 1E1-16
operated at a controlled temperature of about 140F.
through 1E1-22, where operational voltages can be
Module 2A2 is operating satisfactorily when an RF input
signal in the range 7250 to 7750 MHz at a power level of
MAIN POWER circuit breaker 1CB1 is set to ON.
-40 dBm or less has a gain of about 15 dB at the RF
Primary power (120 12 Vac) can be measured at 1E1-
output terminal when the module is at the specified
17 and 1E1-18. Voltages on terminals 1E1-19 through
temperature. The operator cannot adjust any part of the
1E1-22 are a function of the pressure (vacuum) in
internal RF circuits: pump filter FL1, isolator AT1 and
Module 2A3. Terminal board 1E1 provides the only
Mount Circulator AR1 (consisting of a paramp varactor
convenient measurement points for the vacuum
measurement circuit. Both VACUUM meter 1M2 and
vacuum gage tube 2A3J2 are precalibrated sealed
2-13