Agent of Chaos

Hopefully someone here can provide some insight for me.
I installed an FM Modulator yesterday. When I first got everything hooked up, I started hearing a clicking sound though the speakers when nothing was playing and the modulator was powered on. But after unplugging a DC/AC power converter, the clicking went away and the sound was just as good as FM quality playback.
But today heading into work, I powered the modulator on and hooked up my Nomad Zen. The clicking sounds came back. When I disconnect the Zen, the clicking sound is still there. So, it's not the Zen itself making the noises.
The modulator is inline with the FM antennae, and is spliced into the wires going into the cigarette lighter.
Hopefully tonight after work, I'll try connecting the modulators power to an external battery source (not sure what I'll use yet) and see if I still get the clicking noise.
Does anyone have any suggestion or similar situations that can shed any light on my dilemma?

Wingnut

I installed XM via the CD-AUX in soldering hack and had alternator whine from th XM. I was able to get rid of it by installing a $3.99 automotive noise filter from Radio Shack (see below) in the +12V acc power line to the XM radio and the noise disappeared. This might work for you as well. I assume the inverter is making noise on the car's +12V source. This should become obvious if you use an external 12V source.
Good luck,
Wingnut

From my post here: https://www.rx8club.com/showthread.p...threadid=24122
"I took it all apart and removed the RCA ground-loop isolator that was attenuating my signal and instead installed a 4-Amp Automotive Noise Filter Kit (Radio Shack Catalog Number 270-030A) to the constant +12V power to the XM Commander and it killed all the alternator whine and other noise. It is just a choke, I cut my +12V constant power supply line to the XM Commander, soldered the in and the out wires and heat shrinked it up and was done. Problem solved. It also included a 220uF 25V electrolytic capacitor that could optionally be placed between the choke and ground, but it added noise so I did not use it. The part was $3.99. There is considerable room under the center console/ashtray area and I had no trouble cramming all my connections under there. I also added a Y and ran a RCA to 1/8" stereo cable back to the cupholder area for a MP3 player. As long as the MP3 player is off, there is no perceptible attenuation by having both XM and MP3 player hooked into the RCAs I ran to the CD unit."

Agent of Chaos

Thank you for the info Wingnut.
I actually pulled it apart earlier tonight and checked the ground and power wires. After 'cinching' up the two wires, I lost the annoying clicking. So my determiniation was a faulty ground, or at least my best educated geuss-timate.
Now if I listen closely or have the volume jacked up to max, I can hear the altenator whine as you noted in your post. Since there is plenty of room behind the ashtray, I may go ahead and install that noise filter. But I'll see if the whine becomes more percetable now that the click is gone. And if so, I'll meander down to the local Radio Shack and order or pick one up.

Thanks again!

Agent of Chaos

Well, after tinkering with the modulator some more this weekend, I decided it wasn't worth it. I did try the noise filter(270-030A) but I still heard too much static. I'm assuming because it was a clear day and there are a couple strong Radio Signals at the same two frequencies as the modulator.
I may look into purchasing the MP3 CD player and install that. Or look into modding the current CD player and soldering the line in wires to that.
Thanks for all the help though.