Service

Model 8904A

Key Sequence

Annunciator

Status

IC on A2

Pin

Level (lTL)

(None)

FLOAT 1

On

U38

13

L

SHIFT FLOAT 1 OFF

 

Off

 

 

H

(None)

FLOAT 2

On

u35

13

L

SHIFT FLOAT 2 OFF

 

Off

 

 

H

(None)

ON 1

On

u 2

16

L

SHIFT OUTPUT 1 OFF

 

Off

 

 

H

(None)

ON 2

On

u 2

17

L

SHIFT OUTPUT 2 OFF

 

Off

 

 

H

3.HP-IB Annunciators Check

a. On the Multifunction Synthesizer, press SHIFT PRESET. After the instrument presets, key in

SHIFT SERVICE

NEXT NEXT

f3 (Memory Map Access)

NEXT NEXT

The four front-panel, HP-IB annunciators (RMT, LSTN, TALK, and SRQ) should be on. (Pins 15, 14,13, and 12, respectively, of U2 should all be TTL low.)

b. Key in 0 F. The HP-IB annunciators should be off. (Pins 15,14, 13,and 12 of U2 should be high.)

Note: J1 is the 22 pin connector on the front right edge of A2. Pin 1 is nearest the center of the board. The +5V supply is on pins 1 and 2 of J1.

8-40Troubleshooting (Digital/Keyboard Interface)

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Agilent Technologies 2712A, 2948 manual F3 Memory Map Access, Key Sequence Annunciator Status IC on A2 Pin Level lTL