JBL EON15 G2, Техническое и сервисное руководство

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Signal Peak LED Circuitry
This is the signal indication circuitry for the EON15-G2 that is located on the signal input PCB. The
presence of signal, the peak input signal and/or instantaneous signal overmodulation from both the
high frequency and low frequency amplifiers is shown.
Indication consists of voltage network of LED diodes, DS1, DS2, and DS3 connected in series with
each internal node encompassing IC detection circuitry. Any voltage from the low frequency
amplifier or the high frequency amplifier that is above the voltage drop of D1 or D2 (located on main
PCB) will toggle U6C. This, in turn, will toggle U6D and forward bias the “peak” LED (DS3) emitting
light. Similarly, the “line” or “mic” mode is determined by the position of SW2 (not shown—see input
circuitry description). U6A (not shown) to toggles and U6B (not shown) toggles when multi-switch
SW2 is in the “mic” position thereby illuminating the LED.