Service Manual Part 1
"8-
"8"8 )#9!*&,!
Connect an audio millivoltmeter and an oscilloscope across the speaker terminals.
Connect an on-channel RF signal generator to the antenna input socket, with the
output set to -107dBm (1V) modulated to ±5kHz (±4kHz) [±2.5kHz] deviation at
1kHz AF.
Set the volume control to the onset of clipping.
The receiver output should be 4.2Vrms across 4Ω at +13.8V supply.
Check the distortion with the aid of a distortion analyser connected across the
speaker terminals.
The distortion should not exceed 5%.
"8"8" )#9
Connect a sinad meter across the speaker terminals.
Connect the signal generator to the antenna input terminal.
Set the signal generator accurately on the receive frequency.
Set the modulation for ±3kHz (±2.4kHz) [±1.5kHz] deviation at 1kHz AF.
Increase the signal generator output until a 20dB sinad is reached.
Switch off the signal generator modulation.
Couple a 10.7MHz reference oscillator loosely into the receiver IF stage, tune the
signal generator for a zero beat, then uncouple the reference oscillator.
Set the signal generator deviation to ±3kHz (±2.4kHz) [±1.5kHz] at 1kHz AF.
The modulating frequency must match the notch of the sinad meter.
Set the signal generator output level to -127dBm.
Disable the squelch control circuitry using the
key on the T2010,
T2015, T2020, T2050 or T2060, the
key on the T203X, or “function
21” on the T2040. The LED should then flash.
Increase the signal generator output level until a sinad of 12dB is reached.
The signal generator output should not be greater than -117dBm and is typically
-119dBm.
Fn