QuestionJust bought a2007 Chevy Express Cargo Van. The factory radio caused severe motorboating, especially on low power AM stations. Acceleration also caused much static. I had Best Buy replace the radio with a new Kenwood cd deck. They had to use $200. piece to interface with the van computer. All the previous problems remain, and I'm also hearing a sound similar to drum sticks being knocked together every two seconds. Best Buy thinks that grounding the antenna ina different area may help. What do you suggest?
AnswerHi Mike,
Sorry about the delay in answering your question.
I'm not sure that it's really practical to change the antenna ground point without changing the antenna; the factory antenna is simply grounded through its mount on the fender. They can try adding another ground connection; I've sometimes had some success with connecting a wire to the outside shield at the antenna plug, behind the radio, and running it to chassis metal. However, it's not a guaranteed solution.
How's the FM reception? Are you getting the "drum stick" noise with other audio sources, like CD, or just with AM radio?
Unfortunately, an "upgrade" to an after-market head unit often results in a downgrade in radio reception, especially AM reception. The AM radio tuner really isn't a priority for most after-market head unit manufacturers.
It's possible that there's something about your van's ignition system that's causing interference for the AM radio signal. One thing you can do is make sure there's a ground strap from the hood to the vehicle chassis; an ungrounded hood can often cause radio interference. You might also try a different antenna altogether; possibly an amplified antenna designed to mount on the window glass inside. It might not improve the radio reception, but it's worth a try.
Hope this helps!
Brian
