Speaker Interference

[cliouk]

I recently purchased a Sony Head unit last week, wired it up and alls good radio and cd player working fine. But then i started the engine and started to get interference on the radio stations. When i turned off the ignition the interference stopped but the CD player works fine with the ingnition on or off.

Any indeas do i need a new arial or what ?

 

[Bryan]

it wont be the aerial

it will be something to do with the earths on the car

usually a dodgy earth, usually from a light, causing the problems

 

[AliasOmega]

Hello...

How old is the car..?

What you mean by the radio..? is it in FM..MW LW..?

You will find that FM works different, as FM sends 3 radio signals into the radio, so therefore you get the better sound quality than the MW LW (aka AM). The higher the frequency, the shorter the aerial..so hence the tiny mobile phones...<--get it..

Now..MW + LW... These use really really low frequencys so therefore need a longer aerial, and the signal is only 1 signal, so therefore i can be affected. Thats why you lose the signal when you go under a bridge in AM...



So what causes this..? If you are using LW or MW...aka Virgin 1152 or Atlantic 252....Radio 5 live...909.....



The alternator is a generator, inside this, there is a motor which is made up of a iron core with copper windings wrapped around this, this creates eddy currents, which are put up the care wire, chassis etc..So im MW + LW (aka AM) you find that if you put the radio on, and engine, and rev the engine you hear a high pitch squeal, and tone change..



How can i fix this..! Go to halfords as ask for suppressor..aka suppression unit, which should filter the interferance out..

What id do..!

1. Suppression Unit.. (goes inline of alternator...)

2. Aerial... doh...(monkey see monkey do)

3. Radio...



Alias....



aka Aircraft Radar, Comms, Navigation, Weapon Aiming -- Expert..

 

[Bryan]

Quote: Originally posted by AliasOmega on 09 September 2003
1. Suppression Unit.. (goes inline of alternator...)


why mask the problem when you can solve it??

suppression units are almost pointless, as for the money you spend on one, you could have sorted the problem out and spent the money on something more interesting

 

[AliasOmega]

Id go for the suppression unit, but in my defence...there was no fault diagnosis....a few qs to ask..

Was the head unit new..? If not, did you see it working before..

What car is it fitted to.?

Have you dont any work recently which could affect this.

I recently had a prob with a Sont Head Unit which was prone to cutting out when the volume was cranked up above 23 with loud off, and bass down.. I send it back via AEL ?? AEI...? to Sony, and it had a Fader contol unit replaced, came back and was u/s (unserviceable) again..so I got a kenwood..now thats pukka..



If mr blokey has been stripping parts off here and there..making it a 10 sec car..he may have pulled this one off..



I say ignore the radio...and unplug the aerial..only if you connected the earth to the head unit..(some peeps cant be bothered) and play ya Cds...!



Alias