HP 654A - Amplitude Accuracy Checks - UNBAL

Model 654A Section V
Table 5-2. Frequency Accuracy Check
FREQUENCY
DIAL RANGE
ACCURACYIN DICATION
COUNTER
Counter set to
Period Average
1
X10
± 3%
100ms ± 3ms
2.5 X10
± 3%
40ms ± 1.2ms
5
X10
± 3%
20.0ms ± 0.6ms
8
X10
± 3%
12.5ms ±. 375ms
10 X10
± 3%
10.0ms ± 0.3ms
1 X100
± 2%
10.0ms ± 0.2ms
2.5 X100 ± 2%
4.00ms ±. 08ms
5
X100
± 2%
2.00ms ± 0.04ms
8
X100
± 2%
1.25ms ±. 025ms
10 X100
± 2%
1.00ms ± 0.02ms
Counter set to
Frequency
1 X1K
± 2%
1,000Hz ± 20Hz
2.5 X1K ± 2%
2500Hz ± 50Hz
5
X1K
± 2%
5,000Hz ± 100Hz
8
X1 K
±
2%
8,000Hz ± 160Hz
10
X1K
± 2%
10,000Hz ± 200Hz
1
X1OK
± 2%
10.0kHz ± 0.2kHz
2.5
X1OK
± 2%
25kHz ±. 5kHz
5
X1OK
± 2%
50.0kHz ± 1.0kHz
8 X1OK
± 2%
80kHz ± 1.6kHz
10
X1OK
± 2%
100kHz ± 2kHz
1
X100K
± 2%
100kHz ± 2kHz
2.5
X1OOK ± 2%
250kHz ± 5kHz
5
X100K ± 2%
500kHz ± 10kHz
8
X100K
± 2%
800kHz ± 16kHz
10
X1OOK
± 2%
1,000kHz ± 20kHz
1
X1M
± 2%
1,000kHz ± 20kIlz
2.5
X1M
± 2%
2,500kHz ± 50kHz
5
XlM
± 2%
5,000kHz ± 100kHz
8
X1M
± 4%
8,000kHz 1:320kHz
10
XlM
± 4%
10,000kHz ± 400kHz
in step b. Set IMPEDANCE to 75 UNBAL;
in step c. The ac differential voltmeter indication
should be between . 8573V rms and . 8747V
rms.
b. If the tolerances are not met, first assure that the
50 ohm output is correct ( Paragraph 5-10) then
troubleshoot the instrument. The trouble will
most probably be in either the 50 ohm or 75 ohm
impedance networks on the A4 board.
5-12. 135 BAL AMPLITUDE ACCURACY.
a. Connect the equipment ( shown in Figure 5-2), in
the following manner:
1) Connect a 67.5 ohm resistor ( use two 135 ohm
resistors in parallel, RI and R2) across two BNC
to Binding Post Adapters as shown in Figure 5-2.
2) Connect the adapters to the two output
terminals of the 654A.
3) Connect the ac differential voltmeter across the
resistor which is connected to the 654A
UNBAL terminal. Be sure to connect the
ground lead of the voltmeter probe to the
grounded side of the resistor.
b. Set the 654A controls as in Paragraph 5-10b
except set IMPEDANCE to 135 BAL.
c. Record the ac differential voltmeter indication.
d. Disconnect the voltmeter from the one resistor
and record the voltage across the other resistor
(connect the ground lead as before).
e. Add the two voltages recorded in steps c and d.
The total voltage should fall between 1.150V rms
and 1.174V rms, verifying an absolute level of
+10dBm, +/- 1%.
f. If the tolerances are not met troubleshoot the
instrument; the most likely problem would be the
135 ohm impedance network on the A4 board.
Figure 5-1. Amplitude Accuracy Checks - UNBAL
5-3