Ask Max: Bodelin iPod Wireless Auto Adapter
There is a very steady and annoying low-frequency hum that comes across my FM received in my car when I use my iPod with your wireless adapter. This happens regardless of the (free) channel I find. I do not hear any such hum when I use normal FM stations (the test is: turn up the volume and wait for dead air or a quiet passage in the music – hum with the Bodelin no hum on std FM stations).
I have also noticed that lots of static comes through as I drive through the city (Seattle), which also does not happen unless I am tuned to a VERY faint FM station.
I will say that other than the hum and the static your product works great! Any suggestions?
This is a common complaint among FM transmitter owners. Particularly those who live in the city or near broadcast towers. The hum that you hear is caused by the iPods FM transmitter competing with static noise and signal bleed from other stations. Modern stereos use a static damper to reduce the static you hear when tuning your radio. The static is still there but just muted so you don't blow out your speakers when scanning for stations. You still hear some static but not all of it like when we tuned radios with an analog knob. This dampening feature is great for tuning an FCC regulated station, but hard when trying to find an interference-free station. Car radios further complicate this problem by moving into and out off radio tower range. As a test, find a place you can park for a time. Try to find a place halfway between your most common destinations. Start playing the iPod and slowly change the transmitter frequency. Tune your radio to that station then pause the music and see if it hums. Keep working your way through the available frequencies, making note of the ones with the least hum. When you are done, you just need to choose the best of the best. In my experience, lower frequencies work best.
I hope that works to find an open channel in our over-packed airwaves.