Signal Input Assembly Trouble-shooting
EON PowerSub
35
A) Initial Setup
Connect board under test to a +/– 15V power supply at the designated connector pins.
Connect Generator output to XLR input connector.
B) Power supply Test
Verify that +15V and –15V supplies are at the correct levels.
Check for shorts from +15V to ground, –15V to ground, and +15V to –15V. Check for
opens on +15V and –15V lines. Verify that D1, D2, D5, and D6 are not shorted.
C) Gain Test
1)
Turn on Generator, set frequency to 400Hz and level to 1V P/P. Adjust volume control,
R16, fully clockwise.
2)
Verify that voltage at output, pin 1 of J4 = 3.8V P/P (+/– 100mV).
3). Verify presence of 500mV P/P (+/– 50mV) at pin 1 of U1.
4)
Remove oscillator connection to XLR input. Verify resistance from pin 2 of J1 to pin 2
of U2 = pin 3 of J1 to pin 3 of U2 = 6.49k, if this is not the case, check for shorted and/or
opened traces of phase switch, SW1. Also verify resistance from pin 2 to pin 1 of U2 = pin
3 of U2 to ground = 3.2k, if not, check for opened and or shorted traces around U2.
5)
Rotate volume control counter clockwise while monitoring voltage at the junction of pin
2 of R16 and C10. Voltage should gradually decrease to zero. If level is intermittent or
control does not attenuate, replace defective pot R16.
D) Common Mode Rejection Test
Set Generator output drive to unbalanced. Adjust frequency to 400Hz. Bring volume
control fully clockwise and adjust oscillator output to obtain 4V P/P at pin 1 of J4. Lift leg of
R1 that is closest to J1 and solder it to leg of R2 that is closest to J3. Reapply power to
board and verify that the voltage present at pin 1 of J4 is less that 250mV P/P.
E) “Phase LED Test”
Set phase switch in, SW1, and verify that “Phase” red LED, D4, lights. If the voltage across
D4 is greater than 3V, replace LED.
F) Signal Indicator Test
Set oscillator frequency to 400Hz. Adjust oscillator level for 300mV P/P on pin 1 of U2.
Verify that signal LED, D7, is on. Turn off oscillator and verify that signal indicator turns off.
If the above test fails:
Содержание EON Power10
Страница 23: ...High Frequency Response EON Power15 and EON15P 1 230 33 ...
Страница 24: ...Low Frequency Response EON Power15 and EON15P 1 230 34 ...
Страница 30: ...Low Frequency Response EON PowerSub 40 ...
Страница 35: ...High Frequency Response EON Power10 45 ...
Страница 36: ...Low Frequency Response EON Power10 46 ...
