JBL EON15, Введение и общая информация

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G) Mic Amp Frequency Response Test
Adjust for 20V P/P at 400Hz at pin 1 of J1. Adjust frequency to 20kHz and verify 20V P/P
(+/– 1V) at pin 1 of J1. Adjust frequency to 20Hz and verify 14V P/P (+/– 2V) at Pin 1 of J1.
H) Signal Indicator Test
Set oscillator frequency to 400Hz, Mic/Line switch, SW1 to “Mic” position (In). Adjust
oscillator level for 150mV P/P on pin 1 of U1. Verify that signal LED, D7 is on. Turn off
oscillator and verify that signal indicator turns off.
I) Peak Indicator Test
Set oscillator frequency to 400Hz, SW1 to “Mic” position (In), and Volume control, R25 fully
clockwise. Adjust oscillator level for 20V P/P on pin 1 of J1. Verify that Peak LED,
D5, as well as signal LED, D7 are on. Turn volume control down and verify that Peak
indicator turns off.
A) Initial Setup
The easiest way to drive the EON Power10 Main Board is to connect it to a known good
EON Power10 Input Board. Interconnect both boards using a 7-pin cable assembly. Place
the input board in “Line” mode (SW1 out). Advance volume control on input board, R25,
fully clockwise. Attach power transformer to J7. Connect the low frequency output to a 4
ohm load and the high frequency output to a 8 ohm load. Connect generator output to
input board’s XLR connector. Generator should be turned off.
B) Main Test Loop
M15V supply while slowly advancing Variac that is powering primary of power
transformer. Watch the input watt meter, the input volt meter, and the voltmeter on the
+15V supply. Verify the following:
1. Excessive power not pulled. Slowly advance input power (Don’t allow +15 supply to go
higher than 16V). If power pulled is greater that 20W, before reaching 120VAC in, refer
to “Excessive Line Power Test”.
2. As you ramp up the input voltage, verify that +15V supply stays in regulation. If supply
is non-existent or excessive refer to “+/– 15V Supply Test”. Verify –15V supply is proper, if
not, refer to above test.
3. Check –31V (TP4) and +31V (TP5). If non-existent refer to “+/– 31V Supply Test”.
C) Confirmation of Low Frequency Chain
Amp Assembly Trouble-shooting
EON Power10