AR 10044831, Operating And Service Manual

Page: 26 / 52

Model 175A400
8 Rev C
Figure 2-2. Model 175A400 Rear Panel
2.2.1 Local Control Interface
This section describes local operation of the 175A400 using the human interface items found on the control
panel.
2.2.1.1. Toggle Switch
The Toggle Switch is provided for protection from unexpected remote control of the 175A400. The 175A400
can only be turned on locally when the Toggle Switch is in the LOCAL position. Likewise, the unit can only
be turned on or controlled remotely when the Toggle Switch is in the REMOTE position. All remote queries
are processed and responded to in either of the two Toggle Switch positions.
2.2.1.2 Power Button
The momentary POWER button turns the main power to the 175A400 on and off. The status of the green
light-emitting diode (LED) in the switch indicates whether the 175A400 power is on or off. The main power
supply fans are active when power is on. The LCD touch display is active as long as the main circuit breaker
for the 175A400 power entry module is on.
2.2.1.3 Adjust Knob
The ADJUST knob is used to set the RF Gain of the amplifier. The range of RF Gain is 0 to 100 percent.
The ADJUST knob can be rotated both clockwise and counterclockwise 360 degrees.
2.2.1.4 Touch Screen
The Touch screen is a color LCD that can accept single touch events from soft blunt objects such as a human
finger. The mechanism that registers touch events is resistive based and relies on pressure not capacitance.
Menu options presented on the touch screen are typically gray in color with a black text label in the center.
When a valid touch event is registered, a thin black box appears around the valid touch location and an
optional audible beep will occur.