AML ez2254, Инструкция по сборке

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ez2254 Calibration procedure – rev 1
1] Place the unit on a flat level surface (power off). Using a flat blade screwdriver, adjust the plastic screw on top of the meter so that the needle is just off the plastic end stop at the left.
2] Make sure the mains voltage selector switch is in the correct position.
3] Turn on the power.
4] Set the controls as follows:
Switch “SYS” to out
Switch “COMP” to out
Compressor “THRESHOLD” to “0”
Compressor “RATIO” to “1.5:1”
Compressor “RECOVERY” to “400”
Switch “LIM” to out.
Limiter “LEVEL” to “8” (4 clicks up from “4”)
Limiter “RECOVERY” to “100”
Gain Make-up to “0”
Switch “METER” to “In” (left).
5] Apply a 1kHz, 0dBu (775mV rms) balanced signal to the input of the unit.
6] Measure the output from the unit. It should be 0dBu (775mV rms).
7] Switch “SYS” to IN.
8] Measure the output from the unit. Adjust R93 (“Set Gain”) until the output returns to 0dBu (775mV rms).
9] Measure the DC voltage across R120 (it is located between the output transformer and the 24v regulator).
10] Adjust R66 (“Set Bias”) until the voltage measures 120mV DC.
11] Adjust trimmer R45 (“Input Meter”) until the meter registers exactly “0” on its upper scale.
12] Put the meter select switch into “OUTPUT” (right).
13] Adjust trimmer R100 (“Output Meter”) until the meter registers exactly “0” on its upper scale.
14] Apply a 1kHz, +20dBu (7.75V rms) signal to the input of the unit.
15] Switch “LIM” to In.
16] Measure the output from the unit. Adjust R95 (“+8 Threshold”) until the output measures to +8dBu (1.95V rms).
17] Switch “METER” to “G/R” (centre).
18] Adjust trimmer R51 (“G/R Meter”) until the meter registers “12” on its lower scale.
19] Switch “LIM” to Out.
20] Apply a 1kHz, 0dBu (775mV rms) balanced signal to the input of the unit.
21] Switch “COMP” to In.
22] Measure the output from the unit. Adjust R4 (“Comp Threshold”) until the output returns to –0.100dBu (765mV rms).