System Clocks; Vocon Audio Paths; Figure 4-6. Control Top Flex - Motorola ASTRO XTS 5000 Detailed Service Manual

Detailed Theory of Operation
To Controller
J101
UNSW_B+ (33)
+3V (35)
TOGGLE SWITCH (TG1)
VOL (31)
EMERG (14)
B+_SENSE (32)
GREEN_LED (22)
RED_LED (21)
INT_PTT* (38)
RTA0 (27)
RTA1 (24)
RTA2 (26)
RTA3 (25)
SECURE/CLEAR (TG2)
SWITCH (23)
DGND (15)
MONITOR (17)
BL_EN (20)
INT_SPKR (40)
SPKR_COM (37)
INT_MIC (36)
AGND (39)

4.3.4.7 System Clocks

The Patriot IC is supplied with two clocks. The first clock, a 16.8 MHz sine wave, comes from the RF
interface connector P201 pin 7. It is conditioned by the clock buffer circuit, which includes Q450,
Q451, L450, C450, C452, C452, R450, R451, R452, R453, R454, and R455. The output of this
buffer (C452) goes to the Patriot IC CKIH pin as well as the Flipper IC REF_16_IN (C307).
The other clock supplied to the Patriot IC is a 32.768 kHz square wave. This clock is generated by
the Flipper IC internal oscillator and an external 32.768 kHz crystal Y301 and is connected to the
Patriot IC CKIL pin.
4.3.5

VOCON Audio Paths

This section describes the VOCON transmit and receive audio paths.
Audio and DC Circuits on page 9-22
68P81094C31-O
: VOCON Board
S1
S901
R901
ON/OFF
5 4 3
(34)
1
U1
2
Zone/Channel
4
Select
8
B
C C A
1
2
1
C1
2

Figure 4-6. Control Top Flex

for schematic details of the following discussion.
VOL
+3V
2 1
R1
91K
+3V
D1
4
3
R2
68K
1
2
R3
150K
SW2
PTT
+3V
LS1
MIC
SW3
TOP BUTTON
1
2
S2
TOGGLE
SWITCH
SB1
(MON)
SB2
SB3
D2 D3
4 3 4
2 1 2
D5 D6
3
4 3 4
1
2 2
D4
4 3
1
2
MAEPF-27416-O
See Figure 9-16. VOCON
April 15, 2002
4-25
+3V
3
1
1