(3) Output Level Meter. This meter monitors the level of the Video
Amplifier output to the counter.
When the meter indicates in the green
portion of the scale, the output to the counter is satisfactory.
(4) Output. This BNC connector, when terminated in 50 ohms, provides
a signal identical in frequency and amplitude to the Video Amplifier output
to the counter.
Figure 2.
Controls, connectors and indicators.
2.
OPERATION.
a. General.
The Video Amplifier plug-in unit is ac coupled but does
not change any functions of the counter in which it is installed. Using the
plug-in; period, multi-period, frequency, totalizing and ratio measurements
can be performed with input signals as low as 1 millivolt.
b. Operation with Pulse Input Signals. The Video Amplifier is designed
to amplify sinusoidal input signals.
However, pulse input signals can be
amplified if the output signal is monitored to ensure a satisfactory output
to the counter.
Monitor the signal at the Output connector with an
oscilloscope and set the Sensitivity control for a level which results in
satisfactory counter operation (stable display). Because the Output Level
meter is an average responding device, it will read low with a pulse input
signal. Do not use the meter as an output level indicator when amplifying
pulses.
85
Previous Page
