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AV35 Adjustment/Performance Verification Procedures
AM Tuner General Test Setup
Refer to the figure below. The equivalent field
intensity is 26 dB less than the generator output
level or 1/20th of the output voltage. The signal
levels given do not include this factor. Measure-
ments are taken from the record output.
Setup a computer to issue TAP commands. See
page 66 for instructions.
1. AM Sensitivity Performance Verification
1.1 Set the RF generator output for a 55 dBuV/m field
intensity, 30% AM modulation, 1 KHz and the unit and
RF generator to 1080 kHz.
1.2 The headphone output should measure < 10%
THD+N.
2. AM Stop Level Adjustment, TAP
2.1 Set the RF generator to 1080 kHz, 30% AM
modulation, 1 kHz modulation, 57 dBuV/m field
intensity at the unit’s antenna.
2.2 Issue the TAP command TM set 2.
2.3 Set the generator to 1110 kHz , 61 dBuV/m field
intensity.
2.4 Place the unit into seek and verify the unit stops
at 1110 kHz.
2.5 Switch the RF generator for a 51 dBuV/m field
intensity and verify the radio does not stop at 1110
kHz.
FM Tuner General Test Setup
Connect the signal generator to the FM antenna
jack J2001 using a 50 to 75 Ohm matching
network. Adjustments to the procedure’s stated
signal levels should be made to account for a
signal level loss due to the matching network
and/or any other losses.
Setup a computer to issue TAP commands. See
page 66 for instructions.
3. FM Signal to Noise
3.1 Set the RF generator to 98.1 MHz, 1 kHz mono
modulation, pilot off, 75 kHz deviation, 65 dBf at the
unit’s FM antenna input.
3.2 Adjust the unit to 98.1 MHz.
3.3 Reference a dB meter to the left headphone
output.
3.4 Turn off the modulation and pilot. The left
headphone output should measure < -55dBr.
4. FM Sensitivity Verification
4.1 Set the RF generator to 98.1 MHz, 1 kHz mono
modulation, pilot off, 75 kHz deviation, 20 dBf at the
unit’s FM antenna input.
4.2 Measure the distortion at the left or right head-
phone output. It should be < 3.0% THD+N.
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