I have no aux in capability on my car (2000 Astra Estate). It has the existing CD player which has the separate display and steering wheel controls which I am happy with. Has anyone used a fm modulator which mounts behind the stereo and feeds the aux input straight down the antenna cable via 2 selectable frequencies. It has an aux cable with headphone jack you can hide in the glovebox.
I’ve got one but it’s a major dismantling job to fit it so would like any reviews etc from anyone who’s tried one.

I just got one of these

I had one years ago attached to my iPod, got to be a royal PITA trying to find frequencies it would work on, even driving between Chippenham and Bath, (12 miles), or Bristol, (25 miles), where there’s both national and local radio stations. If you’re on your own it’s almost impossible to change frequency safely.
I just bought a new head unit with USB, so much easier, and you can get a DAB head unit with USB for not that much more than an FM transmitter. About £75 from Halfords.

I had one for a while and found the same as CountZero. The FM frequencies seem to be pretty clogged up and even driving locally it was hard to find a clear frequency. You’d be better off going for a Bluetooth dongle.

I have a sonichi dab adaptor that broadcasts on fm. It auto tunes itself finding the clearest channel and seems pretty robust. I think it has a aux line in function as well.

I have a Pure Dab Highway fitted to my car which feeds through the aerial socket on an FM frequency. As well as the DAB radio feature it has USB, 3.5mm aux socket and iPod through the USB. As Countzero said there us very little free space between stations which was really annoying to begin with but then I found out you could turnoff the FM pass through leaving you with just DAB and no interference.

I used to have a Dension ICELink that worked in same way as the OP asked – worked perfectly – much better than FM transmitters.

(On an Astra too co-incidentally)

I recommend.

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