AR 350AH1A, Operating And Service Manual

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Rev B 7
2. OPERATING INSTRUCTIONS
2.1 GENERAL
Operation of the Model 350AH1A broadband amplifier is quite simple. The amplifier’s input signal, whether
swept or fixed in frequency, is fed into the jack marked INPUT, and the amplifier’s output signal is taken
from the jack labeled OUTPUT . The unit is turned on by activating the front panel POWER switch. In the
event of a major malfunction, protection is provided by a circuit breaker located on the unit’s rear panel.
CAUTION:
The Model 350AH1A Amplifier is typically not critical in regard to source
and load Voltage Standing Wave Ratio (VSWR) and will remain
unconditionally stable with any magnitude and phase of source and load
VSWR. It has also been designed to withstand, without damage, RF input
levels much greater than its rated input of 2Vrms. However, large signal
levels or transients with high peak voltages can damage the amplifier.
Also, accidental connection of the Model 350AH1A’s output to its input
(either through direct connection or parasitic feedback paths) will cause
oscillations that may permanently damage the unit’s input transistors.
2.2 CONTROL AND INDICATOR FUNCTIONS
The Model 350AH1A’s front panel is shown in Figure 2-1; the unit’s rear panel features are detailed in
Figure 2-2.
2.2.1 Keylock Switch
The Keylock Switch is provided for protection from unauthorized use or unexpected remote control of the
amplifier. The amplifier can only be turned on locally when the Keylock Switch is in the LOCAL position.
Likewise, the unit can only be turned on or controlled remotely when the Keylock Switch is in the REMOTE
position. Placing the Keylock Switch in the INHIBIT position places the amplifier in the off mode and
disconnects primary AC power from all circuits except for the CPU and control circuits.
2.2.2 POWER Switch
The momentary POWER switch turns the main power to the amplifier on and off. The status of the green
light-emitting diode (LED) in the switch indicates whether the amplifier’s power is on or off. The main fans
are active when power is on. The graphic display is active as long as the main power circuit breaker CB1 on
the rear panel is on.