HP 8568B MHZ, kHz, &Xi, the, (dW, +lO, (dB), (mm), Step, Error, Error, ‘Ihble, 0 (ref), 0 (ref), 0 (ref), MARKER A, <*l.O dB, ~f1.5 dB, Frequency, Amplitude

12. Amplitude Fidelity Test

Equipment Frequency Synthesizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 3335A Adapter, Type N (m) to BNC (f) . . . . . . . . . . . . . . . . . . . . . HP 1250-0780

Procedure Log Fidelity

1.Set the frequency synthesizer for an output frequency of 20.000 MHz and an output power level of + 10 dBm. Set the amplitude increment for 10 dB steps.

2.Connect equipment as shown in Figure 2-21.3.Press ~NSTR PRESET) on the analyzer. Key in analyzer settings as follows:

[ C E N T E R F R E Q U E N C Y ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20 MHZ FREQUENCY S P A N ] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50 kHz

CREFERENCE LEVEL) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . + 10 dBm

4.Press MARKER SPEAK SEARCHJ@~K~GTJ~MKR + REF LVL) to

center the signal on the display.5. Key in the following analyzer settings:

FREQUENCY SPAN) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . O Hz

[&Xi, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Hz

6.Press MARKER A. Step the frequency synthesizer output amplitude from + 10 dBm to -80 dBm in 10 dB steps, noting the MARKER A amplitude (a negative value) at each step and recording it in column 2 of ‘fable 2-16. Allow several sweeps after each step for the video filtered trace to reach its final amplitude (see Figure 2-22).

7.Subtract the value in column 1 from the value in column 2 for each setting to find the fidelity error.

			‘Ihble	2-16. Log Amplitude Fidelity
Frequency	1	2				Fidelity Error	Cumulative	Cumulative
Synthesizer	Calibrated	MARKER A		Amplitude	(Column 2- Column 1)		Error	Error
Amplitude	Amplitude		(dB)			WV	0 to 80 dB	0 to 90 dB
(mm)	Step						(9	(dW
+lO	0 (ref)		0 (ref)			0 (ref)
0	- 1 0
- 1 0	-20
-20	-30
-30	-40
-40	-50
-50	-60
-60	-70
-70	-80						<*l.O dB
-80	-90							~f1.5 dB

2 - 42 Performance Tests