SYMPTOM
9.Constant level whining noise (most noise with source unit volume at minimum)
CAUTION:
10.Radiated noise: crackling noise on FM which is not present when playing tape or CD (noise varying slightly with accelerator but is present at all times)
PROBABLE CAUSE
Check for a ground loop in the system. Turn the system off and one by one change the ground connections (by changing to a different contact point,scraping the level constant irrespective of metal clean of any paint, rust or grease). Turn the system on and check for whining noise after each ground change.
Do not disconnect the Power Amplifier's ground when the system is on. This could damage the amplifier.
Check for defective signal cables. Disconnect signal cables at the amplifier and listen carefully for noise. If the noise dis- appears, run a test pair of signal cables. If there is no unde- sirable whining noise, reconnect to the amplifier with the new pair of signal cables. Check battery ground connection to the vehicle chassis to make sure it is tight and clean. Check battery negative terminal connection to make sure it is tight and clean.
Check if the noise is actually radiated noise: Tune a portable radio to the same FM station. Move the portable radio close to the vehicle engine. If crackling noise comes from the portable radio, then the noise you have in your vehicle audio system is radiated noise.Check with a VOM (volt meter) to make sure the antenna is really grounded to the vehicle chassis.
To ensure a true ground, break the plastic covering of the antenna lead and solder a piece of heavy wire (minimum
Ground the other end of the wire at the same point as the radio ground.
Check spark plug wires. They should be
Make sure engine block is grounded to the vehicle chassis at a bare metal spot (scraped clean of paint, rust and grease).
Make sure hood is also grounded. If not, use a ground strap (which is available from any auto parts store) to ground the hood to the vehicle chassis.
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SPECIFICATIONS: |
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| 321QE | 481QE |
Rated Power @ 14.4 V (0.1 % THD) : | 4 x 40 Watts | 4 x 60 Watts |
4 Ohm Stereo |
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Rated Power @ 14.4 V (0.1 % THD) : | 4 x 80 Watts | 4 x 120 Watts |
2 Ohm Stereo |
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Rated Power @ 14.4 V (0.2 % THD) : | 2 x 160 Watts | 2 x 240 Watts |
4 Ohm Mono |
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Frequency Response : | 20 | 20 |
Input Sensitivity: | 0.1 – 5 V | 0.1 – 5 V |
S/N Ratio @ rated power : | 100dB | 100dB |
30 – 300 Hz | 30 – 300 Hz | |
(Continuously Variable, @18 dB/Oct.) |
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30 – 300 Hz | 30 – 300 Hz | |
(Continuously Variable, @ 18 dB/Oct.) |
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Bass Boost Level : | 0 – 18dB @ 45 Hz | 0 – 18dB @ 45 Hz |
Dimensions: | 11"W x 23⁄8"H x 133⁄16"L | 11"W x 23⁄8"H x 143⁄8“L |
| (280 x 60 x 335mm) | (280 x 60 x 365mm) |
Due to continual product improvement, all specifications subject to change without notice.
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