ACCEPTANCE TESTING
6-A-7
FM scale shape
Specification
Range:
1 MHz max for frequencies up to 21.09375 MHz.
Up to 1% of carrier frequency for carrier frequencies above
21.09375 MHz
Resolution:
3 digits
Accuracy:
±
5% of indication
±
10 Hz at 1 kHz rate internal modulation source
Test equipment
Description Minimum
specification Example
Modulation meter
Minimum frequency 20 MHz
IFR 2305 +
distortion option
Test procedures
(1) With the test equipment connected as in Fig. 6-A-5, set the UUT to
[Carrier freq.]
31.64 MHz,
[RF level]
0 dBm then enter the following:
[UTIL]
[Mod'n Mode] [Comp]
[SIG GEN]
[FM2] [Select Source] [Select Internal]
[Internal F4]
[SIG GEN]
[FM1]
(2) The deviation for FM1 can now be entered. Referring to Table 6-A-6, measure the FM on the
modulation meter at the deviations indicated. Check that the measured deviation is within
specification.
(3) Set FM1 to 0 Hz deviation and select
[FM2]
.
(4) The deviation for FM2 can now be entered. Repeat (2) above.
Table 6-A-6 Deviation frequencies
Deviation (kHz)
224 256 289
228 261 293
233 265 298
238 270 302
242 275 307
247 279 312
252 284 316