Agilent Technologies 8564EC, Service Manual

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606 Chapter 12
RF Section
A9 Input Attenuator
Table 12-2 Attenuator Control Truth Table (W11 connected to A14J6)
A14U421
ATTEN
Setting
(dB) 10 dB 30 dB 20 dB
Pin
16 Pin
15 Pin
14 Pin
13 Pin
12 Pin
11
0 L H* L H* L H*
10 H* L L H* L H*
20 L H* L H* H* L
30 H* L L H* H* L
40 H* L H* L L H*
50 L H* H* L H* L
60 H* L H* L H* L
ON OFF ON OFF ON OFF
* reads
≈
0.2 V (floating) when W11 is disconnected
H
≈
28 V L
≈
0.6 V
Table 12-3 Attenuator Control Truth Table (W11 connected or
disconnected from A14J6)
A14U420
ATTEN
Setting
(dB) 10 dB 30 dB 20 dB
Pin 1 Pin 2 Pin 3 Pin 4 Pin 5 Pin 6
0 H L H L H L
10 L H H L H L
20 H L H L L H
30 L H H L L H
40 L H L H H L
50 H L L H L H
60 L H L H L H
OFF ON OFF ON OFF ON
H TTL High L TTL Low