Motorola CDM1250, Basic Service Manual

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3-2 Transceiver Performance Testing
3.3 RF Test Mode
This test mode is for display radios only. When the radio is operating in its normal environment, the
radio’s microcontroller controls the RF channel selection, transmitter key-up, and receiver muting.
However, when the unit is on the bench for testing, alignment, or repair, it is removed from its normal
environment and cannot receive commands from its system. Therefore, the internal microcontroller
does not key the transmitter or unmute the receiver. This prevents the use of a normal tuning
procedure. To solve this problem, a special “test mode” is incorporated into the radio.
l
FPA entry not selected blocks all test modes.
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FPA entry selected and RF TEST not selected blocks RF test mode.
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FPA entry selected and RF TEST selected enables all test modes.
Table 3-2: Initial Equipment Control Settings
Service Monitor Test Set Power Supply
Monitor Mode: Power Monitor Spkr set: A Voltage: 13.2Vdc
RF Attn: -70 Spkr/load: Speaker DC On/Standby: Standby
AM, CW, FM: FM PTT: OFF Volt Range: 10V
Oscilloscope Source: Mod
Oscilloscope Horiz: 10mSec/Div
Oscilloscope Vert: 2.5kHz/Div
Oscilloscope Trig: Auto
Monitor Image: Hi
Monitor BW: Nar
Monitor Squelch: mid CW
Monitor Vol: 1/4 CW
Current: 2.5A
Note: The test mode procedure that follows assumes that the Customer Programming Soft-
ware front panel access (FPA) screen has both the FPA and RF TEST boxes selected.
Select from the programming screen to enable or disable certain features of the radio
RF test mode.