Bose 3-2-1GS Series II Service Manual page 60

19.2 Enter the command TS1A8,0 into the
computer. You will receive an "OK" response
from the console, and the unit will tune to
the appropriate frequency.
19.3 Reference a dB meter to the left audio
output jack on the console test cable.
19.4 Switch the RF signal modulation to the
right only channel.
19.5 Measure the left audio output jack.
It should read -25 dB or less.
20. FM Stop Level
20.1 Inject a 98.1 MHz, 1 kHz mono mod-
ulation, pilot OFF, 75 kHz deviation RF
signal at a level of 23 dBuV emf into J2001.
20.2 Enter the command T3. The tuner
micro tunes the radio, then measures,
reports, and stores to EEPROM the s-meter
level. You should get a response of "Smeter:
xx" from the console, where xx is the read-
ing.
20.3 Set the RF generator for 98.9 MHz, 1
kHz mono modulation, pilot OFF, 75 kHz
deviation RF signal at a level of 28 dBuV
emf into J2001.
20.4 Enter the command TC5. This is the
seek up command. Verify that the unit stops
at 98.9 MHz.
20.5 Set the console for 98.1 MHz.
20.6 Set the RF generator for 98.9 MHz,
1 kHz mono modulation, pilot OFF, 75 kHz
deviation RF signal at a level of 18 dBuV
emf into J2001.
20.7 Enter the command TC5. This is the
seek up command. Verify that the unit does
not stop at 98.9 MHz.
TEST PROCEDURES
60
21. FM Stereo & Force Mono Threshold
21.1 Inject a 98.1MHz RF signal set to 1kHz
stereo L = -R modulation with 10% pilot
modulation and 75 kHz total deviation at a
level of 33 dBuV emf into J2001.
21.2 Enter the command T5 into the com-
puter. The tuner micro tunes the radio, then
measures, reports, and stores to EEPROM
the s-meter level.
21.3 Inject a 98.1MHz RF signal set to 1kHz
stereo L = -R modulation with 10% pilot
modulation and 75 kHz total deviation at a
level of 38 dBuV emf into J2001.
21.4 Re-tune the radio via ETAP by entering
the TS1A8,0 command. You should receive
an "OK" reply from the console.
21.5 Verify that the left channel audio output
level at the console test cable analog out-
puts is > 100 mVrms. On the console dis-
play, verify that the STEREO LED is lit.
21.6 Decrease the RF generator level to a
level of 28 dBuV emf into J2001.
21.7 Verify that the left channel audio output
level at the console test cable analog output
is < 100 mVrms. On the console display,
verify that the STEREO LED is not lit, and
that the console is in mono mode.
22. FM Signal to Noise Ratio
22.1 Set the RF signal generator to 98.1
MHz, 1 kHz modulation, pilot off, 75 kHz
deviation and at the level that corresponds
to 58 dBuV emf into J2001.
22.2 Measure the output level at the left or
right console test cable analog audio output
jack. Reference a dB meter to this level.
22.3 Turn off the RF modulation and verify
that the level drops by > 60 dB.