Maxon SP-1102, Service Manual, Page: 20 / 35

Service Manual SP - 1402
Page 20 of 35
Peak Deviation
a) Select channel 1. (440.025MHz)
b) Set the PTT switch to on.
c) Set audio generator to be 1KHz 100mVrms and connect to radio external jack.
d) Adjust the ±2.0-2.5KHz DEV. (RV2) and check S-band to get ±4.0-4.5KHz DEV.
Receiver Alignment
The receiver is, by design, a broadband device. It should require no special alignment unless
repairs are performed on the receiver.
The following alignment may be performed:
a) Select channel 1 on the radio.
b) Set the RF generator to the receiver frequency and the RF level to 1mV Pd (-47dBm).
c) Set the AF signal to 1 kHz.
d) Set the deviation to:
12.5 kHz channel spacing 1.5 kHz deviations
25 kHz channel spacing 3 kHz deviations
e) Monitor the audio output level and the distortion, setting the volume control to 1Vrms.
Squelch
a) Connect the RF signal generator to the radio.
b) Set the RF signal generator to the receive frequency of the current channel two.
c) Connect the SINAD meter to the speaker socket on the rear panel.
d) Set the volume control to mid-range.
e
) Set the deviation to: 12.5 kHz channel spacing 1.5 kHz
f) Set the AF generator to 1 kHz.
g) With the above setting, reduce the RF level to –130dBm. The radio should be mute.
h) Adjust the RF level until the radio un-mutes. SINAD meter reads 10dB to 12dB. The radio
should un-mute. If radio does not un-mute adjust RV7 for 12.5 kHz channel spacing.
This completes the receiver alignment process.