TB 9-6625-2138-35
Test instrument
Frequency counter indications (Hz)
CLOCK switch settings
Min
Max
9600
9597.12
9602.88
7200
7128.00
7272.00
4800
4752.00
4848.00
3600
3564.00
3636.00
2400
2376.00
2424.00
1800
1782.00
1818.00
1200
1188.00
1212.00
600
594.00
606.00
300
297.00
303.00
200
198.00
202.00
150
148.50
151.50
75
74.25
75.75
(4) Set CLOCK switch to 9600.
(5) Connect oscilloscope to INT XMIT CLOCK (rear panel) connector using a 50Ω
termination. Waveform amplitude will be no less than 2 V peak.
(6) Set PATTERN switch to 1:1 and OFF/LOOP switch to OFF.
(7) Connect oscilloscope without 50Ω termination to BITS LOST connector (rear
panel). Waveform amplitude will be no less than 1.5 V peak.
(8) Connect frequency counter to BITS LOST connector.
(9) Set CLOCK switch to 75. Frequency counter indication will be between 70 and
80 Hz.
(10) Observe that OUT OF LOCK and LOSS OF DATA (RCV DATA INV on some
models) indicators are on.
(11) Set OFF/LOOP switch to LOOP. Frequency counter indication will be between
0 and 1 Hz.
b. Adjustments. No adjustments can be made.
10. Transmit Pattern
a. Performance Check
(1) Set TI as listed in (a) through (g) below:
(a) CLOCK to 9600.
(b) EXPONENT RANGE to AUTO.
(c) SINGLE/CYCLE (PRINTER on some models) to SINGLE.
