AUSTRALIAN MONITOR AMIS120XL Series, Service Manual

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4.5 Check the output of all channels.
4.6 Measure 25V line 70V LINE, 8ohm (32Vac) tol.5%.
4.7 Check tape outputs (L and R) 250mV (+50mV) (Measure on RCA socket).
4.8 Check line outputs. Approx. (2.7V
±
1.5V).
5 Function Checks :
5.1 Check that you have the header link’s on to
a)
Vox muting enabled (Right Side).
b) VCA Con. Disabled (Back Side).
c) Vox relay enabled (Right Side).
5.2 Check speaker selector outputs, both individual and All Call (Check for the reverse action of the
switches).
5.3 Keep signal in CH1 insert ‘INSERT-PLUG’ having external signal of different frequency the out put
should cut off and switch over to applied insert signal, check signal on inset plugs ring terminal with
respective ground should be 300mV. Remove insert plug .
5.4 Keep signal in CH1 short V/C terminals, out put should mute .
5.5 Check Phantom Switch for on/off operation. Measure Phantom voltage on an XLR inputs (should be
14.5VDC)
(Reset the phantom switch) (Phantom power on each XLR can be checked with the LED jig).
5.6
Switch off the set connect battery (24V) check for rated out put power (out put signal will clip up to
2%)
FINAL TESTING
Requirements for final testing :
a. Load 40
Ω
.
b. Multimeter
c. Oscilloscope
d. Microphone
e. Variac
6 Check sensitivity of all channel. (Optional)
6.1 Mic input (CH1-CH4) = 1mV out put =70V (
±
5V)
6.2 AUX input (CH1-CH3)= 150mV out put =70V (
±
5V)
6.3 AUX input (CH4) =150mV out put = 32.5V (
±
1.5V)
6.4 Check the Power bandwidth – (68Hz
±
5Hz – 15KHz
±
2KHz).
6.5 Check Bass control @ 100HZ = +12dB ( TOL +1dB) and treble @ 10kHz = +10dB (tol.
±
1dB)
6.6 Check that input signal and output signal are in same phase by comparing CH 1 AUX Input and all
other Outputs ( 25V, 70v, 4
Ω
, 8
Ω
)
7 Priority check : (optional)
7.1 Plug microphone into input 1 and oscillator to input 3. Check for muting of channel 3.
7.2 Plug microphone into input 2. Check for muting of channel 3.
7.3 Check ‘mute disable’ function. Insert Disable/Enable link (Factory set – ENABLE).
8
Check 4 tone switched inputs. Set output level of tones to approx. 14Vrms (+ 2V) using evac tone.
Check Page chime button for operation. Make sure channel 3 & 4 mutes with any of the tone’s.
9
Check telephone input sensitivity for CH2 (US models only)
Tel input =150 mV out put =70V.
10
Increase the signal such that you get 76V & you can see the overload protection coming on with a kink