Ecleree MPA4-80, Руководство по обслуживанию

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author:
Queralt
date:
000719
approved:
num:
51.0025
version:
01.00
VERIFICATION PROCESS
title:
EP01-99B
ECLER
PRELIMINARY
- Check the Ground Link.
- Check out that there is no shorting between the unit’s mounting frame and the
metallic part of the IC package.
- Set tested unit’s power main switch to Off position.
- While the signal generator is still turned off, adjust the generator’s output in order to
obtain a 1KHz 0dB output signal.
- Connect three bridged 8
Ω
load impedances between outputs 1-2, 3-4 and 5-6.
- Using a set formed by a mVoltmeter and a dual-channel oscilloscope, connect
oscilloscope’s channel one test probe between Output1 and signal ground, and connect
channel two’s test probe between Output2 and signal ground.
- Turn down both input trimming potentiometers to their minimum position.
- Set the following front-end selector switches to the positions as listed bellow:
- IN1/IN1+IN2 to IN1
- IN2/LINK CH1 to LINK CH1
- ST/BRIDGE to ST
- IN3/LINK CH1 to LINK CH1
- IN4/LINK CH2 to LINK CH2
- ST/BRIDGE to ST
- IN5/LINK CH3 to LINK CH3
- IN6/LINK CH4 to LINK CH4
- ST/BRIDGE to ST
- Connect the signal generator’s output to the unit’s IN1 input.
- Connect the unit to 230Vac mains socket
VERIFICATION
- Switch the tested unit's Power main switch to ON. Verify that the power on LED is
lit.
- Set the signal generator to ON. At this point, all Signal Present LED's should light on.
- Turn up channel one's input triming potentiometer, and check that it's sweep is
complete and smooth. At its maximum position, check that Vo=14V, and that the
output signal monitored on OUTPUT1 is only dependent from the INPUT1 signal.
- Turn up channel two's input triming potentiometer, and check that it's sweep is
complete and smooth. At its maximum position, check that Vo=14V, and that the
output signal monitored on OUTPUT2 is only dependent from the INPUT2 signal.
- Both output signals should have no phase differs.
- Now change the ST/BRIDGE selector to the BRIDGE position, and verify that
OUTPUT1 and OUTPUT2 phase differ has turned to push-pull. However, Vo remains
unchanged, 14V. S.P. CHII's LED has turned off, and the unit's channels 1&2 section
is now controlled only by channel one's input trimming potentiometer. Turn it up and
leave it at its maximum position.
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