Motorola SYMBOL MT2000 Series, Руководство по обслуживанию

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from the overall schematic. The following two notes are general and
apply to all schematic and circuit board applications.
1. Unless otherwise stated, resistor values are in ohms (k = 1000),
capacitor values are in picofarads (pF) or microfarads (µF), and
inductor values are in microhenrys (µH) or nanohenrys (nH).
2. DC voltages are measured from point indicated to chassis ground
using a high impedance (10 megohm) Motorola DC voltmeter or
equivalent. Transmitter measurements should be made with a
1.2uF choke in series with the voltage probe to prevent circuit
loading.
Reference Designator
Assignment
Reference designators are assigned in the following manner:
• Units Series = Receiver
• 100 SERIES = Transmitter
• 200 SERIES = Frequency Generation
• 300 SERIES = Miscellaneous
• 400 SERIES = Housing/Escutcheon
• 500 SERIES = Display
• 600 SERIES = Hear Clear Option
• 700 SERIES = Controller
Interconnect Tie Point
Legend
5V REG = Regulated Five Volts
B+ = Battery Voltage (7.5V)
R5 = Receiver Five Volts
T5 = Transmitter Five Volts
CLK = Clock
D = Data
DAC = Digital To Analog Converter
DAC RST = DAC Reset
LCK = Lock
NC = No Connection
SYN = Synthesizer
VR = Voltage Regulator
Integrated Circuit Details
with Pin-Out Names
Because of today’s technology, integrated circuits and special modules
are able to perform a vast amount of functions in a single component.
The components are getting smaller and the number of IO pins is
getting greater, to the point that there is not enough room to put
enough IC information on the schematics and circuit boards. To help
troubleshoot and signal trace this family of radios, several of the IC’s
are detailed with pin-out names and illustrated on the next few pages.
Remember that PBGA components in a radio can be a combination of
OMPAC and/or Glob Top. Although the illustrations on the next few
pages reflect OMPAC devices, like Good-by components are
electrically the same.