Agilent Technologies 1168/9A, User Manual

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20 1168/9A Probe’s User’s Guide
1 Getting Started
` Other Available Accessories
N2880A InfiniiMax In-Line
Attenuator Kit
The in- line attenuators are an accessory for the probes. The
dynamic range of the 1168A/9A probes are 3.3 V
p- p
. If you
need to measure larger signals, the probe’s design allows you
to add the N2880A InfiniiMax in- line attenuators between
the probe head and the probe amplifier to increase the
dynamic range. The N2880A provides two each of 6 dB,
12 dB, and 20 dB attenuators. The attenuators come as
matched pairs and should only be used with each other. If
you look on each attenuator, you will see a serial number.
The pair of matching attenuators in each set will have the
same four digit numeric prefix and will differ by the last
letter (one attenuator in the matched pair will be labeled A
and the other will be labeled B).
Additionally, these attenuators enable you to increase the
offset range of the probe as described in
Table 8 on page 21.
When using the N2880A In- Line Attenuators, the bandwidth
and rise time of your probing system is not affected. There
is, however, a trade- off in noise (refer to
Table 8 ) and in the
accuracy of DC offset relative to the input.
The maximum input voltage of the InfiniiMax probe heads is
±30 Vdc and so they should not be used to measure signals
that exceed this range. This places a practical limit of 20 dB
on the attenuators used with the InfiniiMax probing system.
Larger attenuation ratios will only degrade the noise
performance and gain of the system.
All InfiniiMax probe heads and amplifiers are compatible
with the N2880A In- line attenuators. However, due to the
N5380B dual- SMA probe head’s maximum input voltage