Tektronix TG8000 Service Manual

Mainframe troubleshooting
Mainframe tro
ubleshooting
The following table lists some common problems with the instrument and how
to troubleshoot them.
Table 2-4: M
ainframe troubleshooting procedures
Problem Troublesho
oting steps
No power or lights
Check the ma
in power supply as follows:
1. Remove instrument top cover.
2. Apply AC power.
3. Use a vol
tmeter to check the voltage on TP21 / Fuse F1. Note that TP21 is unlabeled, but is
located just to the left of Fuse F1. (See Figure 2-4 on page 2-18.)
4. If 5 V is not present, replace the Power Supply module.
5. If powe
r is present on TP21, then check fuses F1 and F2. R eplace fuses if necessary.
6. If there still no power, replace the Main board.
Instrum
ent will not boot up
This could be a software version incompatibility issue. Some versions of software will not work
or even boot up with certain m odules installed. To check:
1. Remov
e all generator modules from the mainframe.
2. Power up the instrument and look for error messages on boot up.
3. A fter the instrument boots up, check the software version and upgrade to the latest release
if nece
ssary.
4. Reinstall the modules one at a time and watch for start up messages.
Fault L
ED illuminated
All of the conditions that drive the fault light should be displayed in the mainframe diagnostic
screen. To view the diagnostics:
1. Pre
ss the MODULE button until "Preset" appears.
2. Press the up arrow to get to Utilities, and then press the Enter button.
3. Press the up arrow to get to Diagnostics, and then press the Enter button.
4. Pr
ess the right arrow multiple times to cycle through the following diagnostic s tatus readouts:
Tune
indicates how much the Genlock or GPS reference is pulling the box from the Cal
value. If not externally referenced this will be zero.
Cal indicates the correction applied to the oven to calibrate the clocks.
PLL indicate the lock status of the four secondary audio and video clocks - all should
indicate lock by “LK”.
TEMP shows the temperature of two internal sensors, typically 10 to 20 degrees above
th
e ambient temperature.
Th
e 21 Voltage pages show voltages on various supplies and fuses; all should indicate
“OK”.
The fan speed varies from about 5800 at low temperatures to 12,500 at high temperatures.
5. Repair or replace boards or component as needed to address any issues found.
2–16 TG8000 Multiformat Test Signal Generator Service Manual

Tektronix TG8000 Specifications

General

Brand	Tektronix
Model	TG8000
Category	Portable Generator
Language	English