TM 11-5805-424-15/NAVSHIPS 0967-220-9010/TO 31W2-2G-41
7-7. Timing Tests
a. Test Equipment and Material.
(1) Test Modem, Low- Speed Wire Line MD-674(P)/G.
(2) Data analysis center, Stelma model DAC-6A.
(3) Electronic counter, Hewlett-Packard model 5233L.
(4) Oscilloscope, Hewlett-Packard model 140A with plug-ins 1405A and 1421A.
(5) Hookup wire.
b. Test Connection and Conditions.
(1) Remove the test MD-674(P)/G from its case, and install the repaired MD-674(P)/G in its place, or remove the appropriate plug-in module from the test
MD-674(P)/G, and install the repaired plug-in module in its place.
(2) Install Clock Module Group OA-8072/G (original or repaired) in the MD-674(P)/G.
(4) Strap, together, terminals TP4 and TP5 on PC assembly A1.
(5) Operate all POWER switches to the on position.
Equipment under test
BAUD RATE: As required.
a. Observe indication on 5233L.
BAUDS: As required.
equal to baud rate of equipment
Selector switch: SYNCBIT-
INPUT SELECT: DATA.
under test, 2%.
b. Remove 5233L connections from
b. 5233L should indicate as in a above.
terminals 10 and 11, and connect
them to terminals 1 and 2.
c. Remove 5233L connections from
c. 5233L should indicate as in a above.
terminals 1 and 2, and connect
them to terminals 4 and 5.
JACK SIGNAL SELECTOR:
d. Remove 5233L connector from
d. 5233L should indicate as in a above.
terminals 4 and 5, and connect
them to terminals 7 and 8.
Electronic Counter 52331.
e. Observe both patterns on the 140A
e. Pattern should be of same fre-
quency but not necessarily in
f. Pattern should appear synchronous,
nections from terminals 1 and 2
with all data (input A) and
SAMPLE RATE: Midposition.
(TB2) and connect them to
timing (input B) transitions in
terminals 4 and 5.