Functional
Section 4
Jaguar Audio
page 4.3
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F UNCTIONAL
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DESCRIPTI ON
Backup
U16 provides regulated power, +5V, for the Dual Reference Interface
Card's matrix "B" electronic circuits. U2 and U4 (sync separators) along
with their associated components form the Dual Reference Interface's ma-
trix "B" sync separator network. U2 and U4 can separate the sync signal
from either composite sync or color black video signals. Once the sync
signal is separated, it is provided to U8 (inverter) and to U10 (quad two-
input or gate). U8 and U10 along with U14 form a gating network that
passes the external sync signal to the Jaguar Audio Frame when an exter-
nal sync signal is present.
If no external sync is supplied the gating network will pass the internally
generated sync signal to the Jaguar Audio Frame. Also when the external
sync fails the gating network will illuminate the LED (CR12 or CR13) cor-
responding to the failed sync signal. U4 working in conjunction with U5
generate the matrix "B" internal sync signal.
4.5 64X32 Analog Audio Matrix Card
The 64X32 Audio Matrix Card contains a 64X32 matrix consisting of sev-
eral main circuits. This discussion will be broken down to the main circuits
as they are found on the schematics in Section 6 (Schematics).
Control
The microprocessor controller (U316) is used to interface switch com-
mands from the PRCI control port (U256) to the switch matrix and return
status information to the controller. Communications to and from the sys-
tem controller are through U246, a RS485 receiver and transmitter. Sys-
tem timing is provided to the microprocessor by U1411, a 7.3728MHz
oscillator. The microprocessor divides the timing single from the oscillator
by a factor of four to form the system clock single. Reset for the micropro-
cessor is provided by U317.
U326, a power supply monitor, monitors the output of the 64X32 Audio
Matrix Card's power circuits and reports power fault conditions to the mi-
croprocessor. CR4 is utilized by power supply monitor circuit to provide a
visual indication of power supply fault conditions.
4.4 Dual Reference Interface Card Continued:
