Operating instructions

ACCEPTANCE TESTING
5-4
RF output tests
Carrier frequency accuracy
This check provides a conventional method of checking the signal generator's frequency locking
circuitry. It will confirm correct operation of phase lock loop and dividers. Overall accuracy is
determined by the instrument's internal reference standard.
Specification
Frequency range:
400 kHz to 1.05 GHz
Accuracy:
As frequency standard
Resolution:
10 Hz
Test equipment
Description Minimum specification Example
Frequency counter 400 kHz to 1.05 GHz ,
1 Hz resolution, external standard In/Out
IFR 2440 or
E.I.P.25B
A INPUT
50 LOAD
(only when
using A input)
Ω
BNC RF
OUTPUT
Frequency counter
C2580
UUT
Fig. 5-1 Carrier frequency accuracy
(1) Refer to Results table 5-1 on page 5-31. C
onnect the BNC RF output socket on the UUT to
t
he A input on the counter (2440), as shown in Fig. 5-1. The connection to the A input
should be made via a 50 Ω load, otherwise miscounting could occur.
(2) Lock the reference standards of the instruments together.
(3) Set the UUT to [Rx TEST], RF IN/OUT [SELECT] BNC output, [RF Gen],
[LEVEL] 0 dBm, [FREQ] 400 kHz. All modulation and noise measurements should be
switched OFF.
(4) Set the counter to 1 Hz resolution.
(5) Check that the counter reads between 399.999 and 400.001 kHz.
(6) Repeat for the remaining frequencies shown in Table 5-1, checking that the counter displays
the selected frequency ± 1 Hz. It will be necessary to disconnect the 50 Ω load and
reconnect the UUT RF output to the A, B or C input of the counter where indicated.