Pyle PLMRC400X4 Instruction Manual - Page 10

INTERFERENCE All cables can source and create interference. The power cable and Cinch/RCA audio cable are very prone to interference; the remote cables are less prone. There is often interference caused by the generator (piping), ignition (cracking) or other car electronic parts. Most of these problems can be eliminated by correct and careful cabling. In doing so, here are the following guidelines: • Use only a screened audio cable for the wiring between "low level in" of the ampli er and RCA or DIN output of the radio. • Lay the signal, speaker and power cables separately with enough distance from one another and also from each others car cable. If not possible, you can lay the circuit and ground cable together with the serial cables. Audio and speaker cable should be as far away from these as possible. The REM cable to the automatic antenna output of the radio can be laid together with the signal cables. • Avoid ground loops by laying the ground wiring of all components to a center point in a star-like way. You can nd the best central point in measuring the voltage directly at the battery. Now compare this voltage value with the chosen ground point and the (+) terminal of the ampli er. If measured voltage is only slightly di erent, you've found the correct central. Otherwise you have to look for another point. You should measure with the ignition point for earth being switched on and additionally switched on consumers (rear window heating and light). • If there are pickups from external electrical sources into the speaker cables, divide the core leads and twist them together. • If there are noises from the car electrics, add an interference suppression choke into the power wiring. • If there are humming noises, use thicker ground cables or add further ground cables to the chassis. • To reduce contact resistance and bad loose contact, please solder the cable ends or use multi core cable ends, spade terminals or others. Gold Plated spade terminal are free of corrosion and have the lowest contact resistance. • Should all these meaures be without any success, the use of a ground loop isolator may solve the problem. 10 www.PyleUSA.com