Fluke 9640A Series, Instruction Manual

Page: 72 / 324

9640A
Instruction Manual
3-24
Table 3-4. External Modulation Input Specifications (AM)
Parameter Specification Comments
Connector Type BNC Input Referenced to RF Common (floating)
Frequency Range DC – 220 kHz
10 Hz – 220 kHz
100 kHz max. for
Carrier >125.75 MHz
-3 dB Bandwidth, DC coupled
-3 dB Bandwidth, AC coupled
Sensitivity 0.5 - 400 %/V Continuously adjustable
Input Voltage ±2.0 V pk max. Optimum input range ±0.25 to ±2.0 V pk,
±5 V pk absolute max.
Input Impedance 10 k
Ω
Nominal
Table 3-5. External Leveling Input Specifications
Parameter Specification Comments
Connector Type BNC Input Referenced to RF Common (floating)
Full Scale Voltage 1V – 5 V dc Adjustable for different power meter types,
±5 V pk absolute max.
Input Impedance 10 k
Ω
Nominal
Table 3-6. External Frequency Pull Input Specifications
Parameter Specification Comments
Connector Type BNC Input Referenced to RF Common (floating)
Input Voltage ± 5 V dc. ±5 V pk absolute max.
Frequency Pull ± 0.0001 ppm/V to
± 1.0000 ppm/V Polarity & Sensitivity adjustable.
Input Impedance 10 k
Ω
Nominal
Note
When using External Frequency Pull to phase lock two signal sources over
a wide range of carrier frequencies, it may be necessary to adjust
Frequency Pull sensitivity. This parameter contributes to system loop gain
and in some cases may need to be adjusted to maintain fixed Hz/V rather
than ppm/V
Trigger I/O Connector
The Trigger I/O (input/output) connector is a rear-panel BNC connection that is
configurable as either an input or an output for sweep trigger signals, and as an output for
modulation trigger signals. In either case, this port is TTL compatible. Sweep trigger
input and output specifications for the port are shown in Tables 3-7 and 3-8, respectively.
Modulation trigger output specifications are shown in Table 3-9.
Note
I/O connections to the Trigger I/O connector will often be grounded (e.g.
Oscilloscope or Spectrum Analyzer). Such connection will ground the RF
Common and hence the RF Output of the Instrument. In this circumstance,
common-mode noise or ground loops may degrade performance at very low
output levels.