ACCEPTANCE TESTING
7-10
Carrier frequency accuracy
This check provides a conventional method of checking the signal generator frequency locking
circuitry. It will confirm correct operation of phase locked loops and dividers. Overall accuracy is
determined by the instrument’s internal reference standard.
Specification
Frequency range:
10 kHz to 2.4 GHz
Accuracy:
Determined by the frequency standard accuracy
Resolution: 1
Hz
Test equipment
Description Minimum
specification Example
Frequency
counter
10 kHz to 2.4 GHz
EIP 535B or
IFR 2440
50
Ω
load
(termination)
1 W, 50
Ω
nominal impedance, DC to 2.4 GHz
Lucas Weinschel
M1404N
Test procedure
C3503
UUT
RF OUTPUT
A
INPUT
2440
Frequency Counter
50
load
Ω
Fig. 7-3 Carrier frequency accuracy test set-up
(1)
Connect the test equipment as shown in Fig. 7-3.
(2)
Connect the internal frequency standard from the UUT to the external standard input on the
counter.
(3)
On the UUT set source A to:
[Carr Freq]
10
[kHz]
[RF Level]
0
[dB]
(4)
Record the frequency measured by the counter against each of the carrier frequencies shown
in
Table 7-17.
(Since the two instruments’ frequencies are locked together, the limit is
±
1 digit on the counter display.)
(5)
At 1200 MHz disconnect the UUT internal frequency standard from the counter and instead
apply the external reference. Check the result against the limits.
The test limits quoted are for guidance and assume that the internal frequency standard has
recently been adjusted. Aging and stability have to be considered when establishing the real
test limits. (See
specifications
in Chapter 1).
Where necessary disconnect the 50
Ω
load and reconnect the UUT RF OUTPUT to the B input.
(6)
Repeat (2) to (5) for source B.
