Tektronix TLA Series, Service Manual

Page: 35 / 130

Operating Information
TLA Series Digitizing Oscilloscope Modules Service Manual
2- 7
CH 1, CH 2, CH 3, and CH 4 Channel Inputs.
These BNC input connectors drive the
vertical channel amplifiers and their dedicated digitizers. The TLA7D2 and
TLA7E2 have four input channels as shown in Figure 2--3. The TLA7D1 and
TLA7E1 have the top two channels.
The channel inputs may be set for 1 M
Ω
or 50
Ω
input impedance. Coupling
selections are DC, AC, and Ground. The Ground setting grounds the internal
amplifier, but presents a high impedance to the signal.
READY Indicator. The green LED lights continuously after the digitizing
oscilloscope completes power-on. During normal operation, READY blinks
when an error occurs that generates a message.
ACCESSED Indicator.
The yellow LED blinks on and then off under the
following conditions:
H
Each time communication with the digitizing oscilloscope occurs
H
When the Slot 0 controller asserts the Module Identification (MODID) line
ARM’D Indicator.
The green LED lights when the digitizing oscilloscope is ready
to accept a trigger signal to complete an acquisition.
TRIG’D Indicator.
The green LED lights when a trigger is received for the most
recent acquisition.
PROBE COMPENSATION.
The BNC output provides a signal for adjusting probe
compensation. The square wave frequency is approximately 1 kHz. Amplitude is
500 mV
p-p
into a
≥
50
Ω
load.
The digitizing oscilloscope is controlled by interactive windows through the
Windows application. The TLA Series application consists of the following
windows:
H
System window. This window provides an overview of the entire logic
analyzer. Use this window to navigate through the logic analyzer. Figure 2--4
shows an example of the system window.
Menu Overview