HP 83522A Service Notes page 163

HP 83522A 83522-90003
Table 8-8. Configuration Switch on A3 Digital Interface Board (CHANGE 5)
Switch Number
Description 1 2 3 4 5 6 7 8
Plug-In: 83522A 0 0 0
x
x x
x x
83525A 1 0 0 x x
x x x
83540A 0
1
0 x
x x x x
83545A 1 1 0
x
x x x x
83570A 0 0 1
x x x x s
*No
RF
Power at Power-Up
x x
x 1
x x s
.Y
Maximum
RF Power at Power-Up x
x x 0 x x
s s
-6 MHz/V FM Sensitivity
x
x
x x
1
x
s
s
-20 MHz/V FM Sensitivity
x x
x x
0
x x s
Direct-Coupled
FM
(Note
2)
x x x
x
x 1
x x
Cross-Over Coupled
FM x
x
x
x s
0
x
x
Step Attenuator Option
x
x
N
x
s
s
1
s
NOTES
1. 1 = Switch Open = High
0 = Switch Closed = Low (Ground)
x = Don't Care
2. When direct-coupled FM is selected, FM sensitivity is -20 MHz/V and switch number 5
is overridden.
*With the configuration switch set for an Instrument Preset conditior~ of "RF Power OFF".
bias is removed from A13 YIG Oscillator and A14 Band 0 Atnplifier. In addition, the 8350A
microprocessor issues a blanking pulse to the plug-in. L RFB (Low = RF Blank) biases the
niodu!ator on hard, closing off the RF signal path. When R F power is nlanually turned
011.
via the front panel pushbutton,
L
RFB remains low for a short period to allow the RF ~llicro
circuit components to reach full capacity before releasing the ALC amplifier. This prevents
the ALC loop from correcting for a large error voltage at initial power up. thus preventing
overshoot.
A
CHANGE 5