Test Products International 460 - Manual (Page 61)

Appendix E
Troubleshooting
This chapter provides a resource for troubleshooting the hand-held TPI Scope Plus 460.
Common problems are addressed from the point of view of the new user, and responded to with
methods that correct the problem in a majority of cases. Try these solutions before calling the
TPI service department for assistance.
Coverage
The following troubleshooting problems have been identified. If you find a problem and an
answer which is not in this list, please send it to us for inclusion in the next update of this appen-
dix. If you do not find a question or answer to your current problem, please call a service repre-
sentative from your local dealership, or by calling the number shown on the inside cover sheet of
this manual.
Cannot read screen characters or oscilloscope trace
Some front panel buttons do not give the same results when pressed.
The A460 switches off by itself.
Waveform shapes appear to be effected when using the 10:1 probe.
RS-232 link will not capture waveforms.
RS-232 Waveform updates very slowly
Trouble effectively archiving RS-232 waveforms
Cannot read Screen Characters
The most likely problem is that the contrast adjustment is set incorrectly, or that the memory did
not maintain storage of the settings the last time it was adjusted due to battery disconnection.
Use the procedure provided in Chapter 2 (“Getting Started”) to correct the basic contrast adjust-
ment. Note that the brightness adjustment will also effect readability and may need to be cycled
through its ten steps to ensure the correct level.
Check for cover film. When the 460 is shipped, the screen is covered with a thin mylar film that
is removable but hard to see. Check the edges of the display screen. If you see a raised edge,
use tweezers or your nail to peel the sheet back. You should have a more visible screen as a
result.
E-1
460 User s Guide Troubleshooting