Fluke 6080A - Page 141

TROUBLESHOOTING AND REPAIR
FREQUENCY SYNTHESIS
Table 6C-1. Sub-Synthesizer PCA Test Points
6C-11
Typical:
Range:
TEST
POINT
TP2
TP3
TP4
TP5
TP6
TP21
TP22
TP23
TP24
TP25
TP26
TP27
TP30
TP31
TP32
TP33
TP34
TP35
TP36
TP37
TP38
TP39
TP40
TP41
Front panel frequency set to 804.001499 MHz
Total Sub-Synthesizer frequency range (160-320 MHz)
Front panel from 800.000000 to 807.999999 MHz
SIGNAL
TYPE
ground
TTL
TTL
TTL
DC
TTL
TTL
ground
TTL
TTL
ground
DC
TTL
TTL
ground
TTL
TTL
DC
input
audio
audio
DC
DC
DC
RANGE
20MHz, 12.5 ns (AH)
20MHz, 12.5 ns (AH)
10-19.98 MHz
0-10.23V
1 MHz, 50 ns (AL)
1 MHz square wave
1 MHz, 10 ns (AH)
1 MHz, 150 ns (AH)
2-24V
10-19.98 kHz
1-1.998 MHz
9-19 MHz
0-1 MHz
0-10.23V
10-19.98 kHz
450 mV p-p
10-19.98 kHz
450 mV p-p
0-10.23V
2-24V
2-24V
TYPICAL
Constant
Constant
19.98 MHz
2.2V
1 MHz
1 MHz
1 MHz
1 MHz
8.6V
19.98kHz
1.998 MHz
15MHz
10kHz
50 ns (AL)
1.6V
19.98kHz
19.98kHz
varies
8.6V
8.6V
FUNCTION
2-phase clock generator
2-phase clock generator
Low order digit gate array output
Coarse Loop VCO steering DAC output
N-Divider output
Reference divider output
Phase detector down output
Phase detector up output high
~2.8V, low ~-0.5V
Sub-Synthesizer VCO control voltage
Low order digits signal
Intermediate low order digits signal
(divide-by-10)
Triple modulus pre-scaler output
Modulus select signal
Sub-Synthesizer loop gain
compensation DAC (KN) output
For calibration of low-pass filter
Active quadrature generator output
Active quadrature generator output
Reference oscillator voltage
DAC output
Loop amplifier output
Low-pass filter input TP40-TP41
normally connected together, except
when troubleshooting