Motorola APX 7000 Detailed Service Manual page 32

3-8
Pin
VOCON Signal
No.
24 GROUND
25 LOCK
26 BSTAT
27 TRIDENT_CS
28 UNSW_B+
29 SPI_DSP_MISO
30 UNSW_B+
31 SPI_DSP_MOSI
32 UNSW_B+
33 SPI_DSP_CLK
34 UNSW_B+
35 GROUND
36 UNSW_B+
37 VCC_SW_3.6
38 GROUND
39 GROUND
40 GROUND
3.1.1.3 Antenna Port J101
Antenna port J101 is a surface-mount, miniature coaxial connector for the antenna cable.
3.1.1.4 Serial EEPROM
The electrically erasable programmable memory (EEPROM), U101, holds all of the transceiver
tuning data. This allows transceivers to be tuned in the factory and installed in the field without
retuning.
3.1.1.5 Power Conditioning Components
DC power-conditioning components include zener diodes, capacitors, ferrite beads, a power
inductor, and the fuse. Diodes VR200 and VR101 provide over-voltage protection. Ferrite beads
(designated E, etc.) and capacitors suppress electromagnetic interference from the transceiver.
The power-line filter consisting of L200, C202, and C203 suppresses digital noise from the VOCON
board switching power supplies that could degrade the transmitter spectral purity.
Ground clips M103 through M106 make contact between the transceiver board ground and the radio
chassis. The chassis connection is a necessary electrical reference point to complete the antenna
circuit path. Shields SH1 through SH14 appear on the schematic to show their connection to ground.
Table 3-2. VOCON Connector J1001 (Continued)
XCVR Signal
GROUND
DIG_CTRL_LOCK
DIG_BATTERY_DATA
DIG_CTRL_SPI_TRIDENT_PE
DC_FUSED _B+
DIG_DATA_SPI_MISO
DC_FUSED _B+
DIG_DATA_SPI_MOSI
DC_FUSED _B+
DIG_SPI_CLK
DC_FUSED _B+
GROUND
DC_FUSED _B+
DC_SW1_3_6V
GROUND
GROUND
GROUND
Theory of Operation: Transceiver Board
XCVR
Type
I/O
– – –
O status FGU lock detect
I/O 1 wire IMPRES Battery status
I spi SPI Trident chip select
O dc Fused B+ to VOCON
O spi SPI data out
O dc Fused B+ to VOCON
I/O spi SPI data I/O
O dc Fused B+ to VOCON
I spi SPI clock
O dc Fused B+ to VOCON
– – –
O dc Fused B+ to VOCON
I dc Regulated 3.6 V
– – –
– – –
– – –
Description