Teletype 43K001/AAA, Repair Manual

Page: 32 / 82

525,2-18
B. TROUBLESHOOTING (Contd)
3.
43K001 RO KEYBOARD TROUBLESHOOTING (Contd)
TEST POINTS AND VOLT AGE READINGS
Note: Use Volt-Ohm-Milliammeter de Volts Scale. Voltage readings are approximate and may be higher
or lower than those specified, depending on meter used.
MLA1-7
MLA1-9
MLA2-11
MLA3-3
MLA3-6
MLA3-8
MLA4-1 = +7.5 V
MLA4-12 = +3.5 V
Depress Reset Switch. Meter will momentarily deflect from +4 V to +3.9 V.
Depress and release Printer Test Switch. Meter will momentarily deflect from +4 V
to +3.9 V as switch is released.
Depress and release Printer Test Switch. Meter will momentarily deflect from 0 V
to +0.1 V as switch is released.
Depress Reset Switch = +4 V
Release Reset Switch = 0 V
Depress and release Printer Test Switch. Meter will momentarily deflect from +4 V
to +3.9 V.
Depress Reset Switch = 0 V
Release Reset Switch = +4 V
Depress Reset Switch = +4 V
Release Reset Switch = 0 V
Depress Reset Switch = 0 V
Release Reset Switch = +4 V
MLB1-6
Depress Reset Switch= +4 V
Release Reset Switch= 0 V
MLB1-14 Depress Reset Switch= 0 V
Release Reset Switch = +4 V
MLB4-2, 3, 6 and 7 Depress Reset Switch = +4 V
Release Reset Switch = 0 V
MLB4-12 Depress Reset Switch= 0 V
Release Reset Switch= +3.5 V