Tektronix 1705A TroubleshootingAids

Maintenance
6-8 1705A Spectrum Monitor
Tek
REF
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L
O
G
+f
Figure6 -5: DAC check waveform used to check Focus, Astigmatism, Geometry,and
Tracerotation sett ing
There aretwo additional diagnostic tests that can be made. The LED test
alternateshigh and low levels on the control lines to the front-panel indicators.
It can beused to either locate burned-out indicators (visual inspection of flashing
indicators)or shorted indicator lines (by probing with an oscilloscope).
The Key test simply prints out the name of the key’sfunction when it is pressed.
In both casesthe test is terminated by pressing the INPUT push button.
TroubleshootingAids
Since this manual is alsoa troubleshooting aid, its organization is described here.
This materialis general, and does not cover specific cases.
The foldout pagesat the back of the manual contain block and schematic
diagrams, circuitboard illustrations, and lookup charts.
Diagrams. Schematicdiagrams show the circuit number and electricalvalue of
each component. Symbolsused on these diagrams are defined on the firstpage
of Section 9. Circuitboards are indicated by a heavyborder.
Signals leaving or enteringa schematic diagram are cross-referencedwith the
connecting schematic number in brackets and the sch ematic grid location in
small print.
LED and Key Tests
Foldout Pages