Motorola R-2001A - Code Synthesizer Block Diagram

'
SYNTH 42
REF ——
(1 KHz)
MIC-2.
EXT '4
MOD
A6 AUDIO'S
1
——
"
1
';
1
AUDIO
SYNTH
\
IDC [—
l68 301
/
—————————————'
4S
- AUDIO SPKR
IS . l^.^-MnnniiT
^ 164 421
^
YNTI
SEL
SW
^ESIZER
PRGM
ATTEN
DPL
GEN
1 KHz
BPFL
-^
'>^62 6
bV ^ , I
1 " "" 1 LVL
—————-^- DUPLEX MOD -=•
————p^- DSBSC MOD
'•"• | . CONTROL
|"
SEL 126 .40
CODE ^ .I;
LVL <>
1 —
146 28
1KHz <^
M
^ 1 24 34
no <:,35|
LVL <^
^
•66 "36
r————l <• 3
156, „. S "F
A8 IEEE ^TE?
SEL
SW
SEL
SW
SEL
SW
SEL
SW
FAC
PRGM
ATTEN
PRGM
ATTEN
PRGM
ATTEN
PRGM
ATTEN
A9
ROCESSOR
^w •
1
-
4
IEEE
"BUS
AM
MOD+
DC REF
DRIVER
Figure 5-8. Code Synthesizer Block Diagram
5-63. The three modulation sources are sumed together on the Audio Synthesizer module after the level
controls. The composite modulation signal is then switched to the appropriate modulator and applied to the
modulation determination circuitry (MOD CAL AUDIO), the audio amplifier (SPKR AUDIO), and the
Modulation Output jack (MOD OUT) on the front panel. The signal to the front panel jack is buffered by a Driver
Amplifier to provide a low driving source impedance.
5-64. The AM modulation signal at the output of the Select Switch is sumed with a +5 volt signal. This
combination provides a DC level to control the average output power of the wideband amp in the RF Input
module, and a superimposed modulation signal to give an AM output. The RF Level control on the front panel
for local control or the Programmable Attenuator on the IEEE module provide local or remote RF level control
by simultaneously attenuating the DC level and the modulating signal. The resulting signal is the AM MOD &
DC REFERENCE signal to the RF Input module.
5-16
J