DAB splitter aerial relay

[captain Byrne]

I've spent £200 on a bloody good DAB radio. After reading up & doing a bit of research I decided to wire it up properly (the way most professionals advise). I travel to out of reach places which usually have crappy reception anyway so last thing I want is a bodged job and have to listen to a radio that keeps dropping out... Now to eat an easter egg.

[nicq]

Why don't you fit a DAB aerial and the job is done properly.
Halfords sell them for £14.99

[captain Byrne]

Cos if a splitter is fitted properly it works just as well as a DAB aerial. (sometimes even better).

[nicq]

After reading up on them all they do is disconnect th aerial from the car radio when used on DAB as when connected to the radio it interferes whith the DAB signal. If and that is an if it's better it has an amp in the box.
dAB signals are 140 to 250 MHz which means the antena should be a different length to FM antennas.

[captain Byrne]

And what's a DAB aerial? It's a long bit of metal, same as any aerial.

[nicq]

For an aeria to work properly in poor reception the tuned length gets even more critical.
The frequency change is almost double FM. It's not just a bit of wire!

[captain Byrne]

Fitted externally & vertically to about a 30cm length, (which my existing aerial is) they work extremely well.

[nicq]

It's poss it will work well but DAB range it 120 to 240 fm is 98 to 108 so the ant needs to not only be different length but also wide range. This is usually done by making the ant with a coil of wire either at the base centre or tip, or adjustable down its length.

[ghost123uk]

Doesn't surprise me as it's [the wire] only 300mA.

There is no way the splitter / amp is going to pull anywhere near 1/3 of an Amp. Likely not even a tenth of that. It would be dead quick and easy to temporarily wire it up from any live wire and use your meter to see what current it does pull.

[CovKid]

Quite.

[scottbott]

my wife bought me a DAB motion last year,the included aerial is a stick on one,mine is fitted to the rear screen upside down so the lead to it is close to the hinges and does not move to much,reception is fine,I did enquire with the manufacturers and fitting it that way and they said it would be ok

[captain Byrne]

I just saying that I read a lot of posts on forums where folk had tried the blue/white radio wire for the splitter & it hadn't worked. I'm not spending my hols pulling the radio out of the van to fiddle around with my bloody aerial cos I've got crap reception. Fitting the relay was a 5min job so what's the problem.

E D I T - My splitter instruction manual says: "The supposed +12V switched output from many radios is rather low. It is best, therefore, to connect the adaptor’s red power cable to the switched power supply (normally red) to the radio, not to the switched power supply (normally blue) from the radio. Ideally the connection should be via a 0.5 amp in-line fuse.

E D I T 2 - From dabonwheels: "Some car radios give DAB reception that is not quite as good as might be expected.
It turns out that some car radio units exhibit a voltage drop as high as 3.5 volts between the radio’s supply voltage and the radio’s switched (supposed) 12 volt output, which means that the voltage output by the radio is way too low for the aerial to provide optimum reception. The solution? Easy! Just disconnect the power cable to your aerial from the switched out (normally - but not always - the blue lead) coming out of your radio and connect it to the switched power supply (normally - but not always - the red lead) leading into your radio. Ideally the connection should be via a 0.5 amp in-line fuse.
You will be amazed what a difference a volt or two can make!"

[CovKid]

Well, hopefully it works out for you.

[nicq]

If that is correct keep your eye on the relay as it may drop out with only 8.5 volts to fire the coil.
Good luck

[captain Byrne]

Ah bless... just when I thought I was going to get the last word in.