Robert Hall of Stuart, Florida, asks:
"My stereo system works perfectly, but at a certain time in the afternoon, when the volume is set low, I can hear an annoying tic-tic-tic sound in the speakers when I’m listening to my classical-music station. When I turn the volume up a little the sound goes away. Someone told me it was because I had a cheap audio system so I went out and bought the best. But I still get that tic-tic-tic noise in the afternoon."
Gordon West replies:
If you go to your solar-panel controller and disconnect the panels I almost guarantee the tic-tic-tic noise will stop. Because you are in Florida, your solar panels start charging early in the morning and by the time the afternoon rolls around, the regulator for the solar panels will sense that the batteries are topped off. To decrease the average amperage being delivered to the battery system, the regulator will start to pulse the charge current; this pulsing is what makes the ticking sound you hear in your speakers—and likely in your TV and VHF speakers too.
Later in the afternoon, when the panels aren’t producing much, the regulator will again swing full open and deliver the available charge to the batteries without any pulsing. You might try a different regulator. I run, for example, a 7-amp Flexcharge model PV7D regulator (West Marine model 343329, $89.99; westmarine.com) and I don’t get any pulse noise, even when my batteries are fully charged. Remember that if you turn off the solar charging system and forget to turn it back on, the panels aren’t going to be able to begin their charge process. Also, be sure to cover your panels before disconnecting them.