SECTION V DISPLAY CARD AND FRONT PANEL FUNCTIONAL OPERATION

T.O. 31W2-2GSC24-2

TM 11-5805-688-14-1

NAVELEX 0967-LP-545-3010

5-560. Power supply U48 produces a precision +5-volt

voltage for the APLL circuit.

output that is applied to the SB cards as a reference

SECTION V

DISPLAY CARD AND FRONT PANEL FUNCTIONAL OPERATION

5-567. In the following discussions, the diagnostic

5-561. INTRODUCTION.

circuits on the display card that are active and monitor

the diagnostic signals during normal operation are

5-562. Paragraphs 5-563 through 5-611 contain the

referred to as the primary diagnostic circuits. Diagnostic

block diagram discussion and the detailed circuit

circuits on the display card that are only, active in the

discussion for the display card. The block diagram

self-test mode of operation and test the primary

discussion for the circuits mounted on the front panel is

diagnostic circuits are referred to as the secondary

incorporated in the overall diagnostic block diagram

diagnostic circuits.

discussion in section II, paragraphs 5-154 through 5-163.

Paragraphs 5-612 through 5-614 contain the detailed

5-568. When a malfunction occurs in the multiplexer

circuit discussion for the circuits mounted on the front

set, the faulty circuit may possibly force other circuits in

panel.

the equipment to generate false error signals. The

diagnostic circuits on the display card have an

5-563. DISPLAY CARD.

established order of priority for selecting the probable

faulty source when more than one error condition is

5-564. GENERAL.

detected in the multiplexer set. The display card can

monitor 21 error conditions, which are listed in their order

5-565. The display card contains logic circuits that

of priority in table 5-6.

monitor the diagnostic error signals from the diagnostic

circuits on the common cards and channel (functional)

cards in the multiplexer set. When an error condition is

5-569. FUNCTIONAL

BLOCK

DIAGRAM

detected on the display card, the appropriate display

DISCUSSION.

signals are generated and applied to the front panel to

activate the appropriate digital readout display and

5-570. A diagnostic check of the active channel cards in

indicators as described in the following paragraphs.

the multiplexer is performed during word 24 by the

multiplexer channel card error detector circuits. The

5-566. As shown on figure 5-43, the function switch

status (error or no error) of each channel card is routed

(MUX OFF/DEMUX OFF/ NORM) can be set to the MUX

to the OEG card on the positive stuff re- quest line during

OFF position to inhibit the multiplexer diagnostics or to

word 24. At the OEG card, the signals are multiplexed

the DEMUX OFF position to inhibit the demultiplexer

into one data signal stream. The composite error signals

diagnostics. When both diagnostic functions are

are then applied as signal MPSA- to the multiplexer

enabled, the switch is set to the NORM position.

channel card error detector on the display card.

5-152