2635 manual - BK Precision

ATTN. :
As a protective measure the attenuation should be set to 40 dB
(LED „40“ is lit).
Frequency setting:
Set CENTER FREQ. to 500 MHz (C500MHz) and choose a span
of 1000 MHz.
Bandwidth:
For the first measurements the 400 MHz filter should be selected,
and video filter off.
If the noise band moves upward on screen when decreasing input
attenuation, this indicates a possible other high-amplitude input
signal present but not visible in the chosen frequency range. If no
signal is visible, the attenuation can be consecutively decreased.
In any case the attenuator setting must be in correspondence to
the biggest input signal (not Zero-peak). The correct signal level is
achieved if the biggest signal („0 Hz“ - 1000 MHz) just touches
the reference line. If the signal surpasses the reference line, the
attenuation must be increased, or an external attenuator of suitable
power rating and attenuation must be used.
Measuring in full-span mode serves mostly as a quick overview.
To analyze the detected signals more closely, the span has to be
decreased. Previous to this, the center frequency has to be set so
the signal is at center of screen. Then span can be reduced.
Then the resolution bandwidth can be decreased, and the video
filter used if neccessary. The warning „uncal“ in the readout must
not be displayed, otherwise measurement results may be incorrect.
28 Subject to change without notice