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Chapter 5
Hints and Tips
FAQs and Helpful Hints and Tips
Hints
an
d Tip
s
FAQs and Helpful Hints and Tips
These pages lists a few frequently asked questions (
FAQs
), and gives a
few hints and tips that will help you get the most from your analyzer
and Option 215 External Source Control.
•
Overloading
- if you are overloading the analyzer, connect a 10 dB
attenuator to the RF input and set the
Ext Amp Gain
(external
amplifier gain) to -10 dB. This softkey is accessed via the Amplitude
key and the
More 1 of 3
softkey.
•
How can I increase the measurement speed?
Measurement speed can
be increased by reducing the number of points from the default value
of 601, or by increasing the resolution bandwidth from the
automatically calculated value. Increasing the resolution bandwidth
will improve the measurement speed, but at the cost of lower
dynamic range.
•
Preselector centering does not appear to be working.
Preselector
centering is not compatible with the time gating functionality that
Option 215 External Source Control uses. The way around this
limitation is to switch Option 215 External Source Control
Off
before
centering your preselector. Once the preselector has been
successfully centered, you can switch Option 215 External Source
Control
On
again.
•
Can I make manual adjustments to the preselector while Option 215 is
running?
There are no limitations on making manual adjustments to
the preselector when Option 215 External Source Control is
operating. You can make manual preselector adjustments with
Option 215 External Source Control either
On
or
Off
.
•
I am seeing regularly spaced dropouts (glitches) in my pre-normalized
response. How can I stop this?
There are regularly spaces dropouts in
Option 215 External Source Control’s response. These occur every
1.4 MHz, and are most visible in spans from 8 MHz to 50 MHz. They
are about 0.08 dB in size, and are stable enough to be effectively
removed by normalizing the measurement.
These dropouts get worse if you change the
Phase Noise Optimization
setting from its default setting of
Fast Tune
. With any non-Fast Tune
setting, these dropouts can reach up to 1.6 dB. It is also worth noting
that none of the non-Fast Tune settings work below 2 MHz.
•
I can’t get my signal source to work to the limits of its frequency range.
What is wrong?
You are not necessarily doing anything wrong. If you
specify, for example, that the PSA Series analyzer is to sweep using
601 points, the signal source actually uses 601+2 points, that is, 603
points. This is because the source needs a ‘spare’ point at the start
and at the end of every sweep generation. These two extra points,
although not visible to you, both need to fall within the frequency
range of the signal generator. The frequency span you see can