Tektronix 2714 User Manual page 291

specify the 2714 gain step sizes and the frequency and amplitude of
the internal calibrator signal. The references are determined by com-
parison with an accurate external attenuator and signal source. If
NVRANM is ever lost (for instance, because the battery runs down), the
factory reference normalizations are lost with it, and you must perform
a service reference normalization to achieve maximum accuracy from
the 2714. If you have signal sources available that are more precise
than the on-board calibration signal, they can be used to achieve
added accuracy when normalizing the 2714.
Press [UTIL] [5] [5] to select SERVICE NORMALIZATIONS. Using the
REFERENCE NORMALIZATIONS selection from the Service Normal-
izations menu, you can measure new reference values for the on-
board calibration signal and attenuator with respect to more precisely
known alternate sources. The alternate sources must exceed the
following specifications.
frequency: 5 parts in 107, +10 Hz
amplitude: — 18.8, +0.1 dBmV @ 100, +1 MHz
attenuation (gain step): +10 0.5 dB @ 100, +1 MHz
We will not give examples for all reference normalizations, but we will
show you how to determine a new frequency reference.
Connect an external frequency source to the 2714 input meeting the
frequency specification given above. Various sources are available (for
example, WWYV in the U.S., some broadcast television carriers, as-
sorted frequency standards. A frequency of 100 to 500 MHz would be
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