Indicator radio interfernce
Discussion
Hmmm. No, but...
I assume you are getting a clicking over the speakers in time to the indicator. How irritating.
If you have an aftermarket radio/CD fitted it may be that the wiring for the speakers or the supply for the unit is running alongside the indicator wiring.
If it happens with both left and right indicators I suppose it's more likely to be the supply routing. I had this problem once on a Chimaera, and although I didn't ever try to fix it I hoped that a suppressor on the supply to the radio could help. This could take the form of a clip-on ferrite. You try clipping it over the supply leads at the rear of the radio? (and/or look around for parallel runs of related wiring). Try RS or Maplin? J
I assume you are getting a clicking over the speakers in time to the indicator. How irritating.
If you have an aftermarket radio/CD fitted it may be that the wiring for the speakers or the supply for the unit is running alongside the indicator wiring.
If it happens with both left and right indicators I suppose it's more likely to be the supply routing. I had this problem once on a Chimaera, and although I didn't ever try to fix it I hoped that a suppressor on the supply to the radio could help. This could take the form of a clip-on ferrite. You try clipping it over the supply leads at the rear of the radio? (and/or look around for parallel runs of related wiring). Try RS or Maplin? J
So the interesting thing is it only happens on radio not cd
So it must be some aspect of the led indicator driver circuit...perhaps a switch mode or somthing
The interference is a hiss. Almost enough to drown the audio
Left and right indicators the same and seems to come from left and right speakers together
So it really seems like an rf effect
Even tried turning off the pod squeeker thing to see if that was the culpret...nope
I'm bit baffled. The ferrite idea is probably next
So it must be some aspect of the led indicator driver circuit...perhaps a switch mode or somthing
The interference is a hiss. Almost enough to drown the audio
Left and right indicators the same and seems to come from left and right speakers together
So it really seems like an rf effect
Even tried turning off the pod squeeker thing to see if that was the culpret...nope
I'm bit baffled. The ferrite idea is probably next
Sadly, I was thinking about this last night. There is another scenario: if there is a resistive earth shared by both the indicators and the radio unit, when the extra current for the indicator passes through it in a pulsed way, the supply to the radio will endure a dip in sympathy. The regulators within the radio need a certain amount of headroom voltage in order to reject supply disturbances - so you might get an on/off hissing behaviour.
Check the 12V going to the radio when the indicator is flashing, with a multimeter. Make sure you use a known good earth for the black lead of the meter. The voltage should not dip. If it does, there is a high R connection associated with radio or indicators (could be supply or earth). J
Check the 12V going to the radio when the indicator is flashing, with a multimeter. Make sure you use a known good earth for the black lead of the meter. The voltage should not dip. If it does, there is a high R connection associated with radio or indicators (could be supply or earth). J
PetrolHeadPete said:
Found and fixed
The rear indicator modules use a switch mode to regulate 12v down to 8v ish
Converter is noisy as hell
Modified the circuit to lower the switching freq and used a ferrite in the 12v feed with 5 turns
Sorted!
Not that i have a problem, but undergoing sound upgrades right now so im interested...The rear indicator modules use a switch mode to regulate 12v down to 8v ish
Converter is noisy as hell
Modified the circuit to lower the switching freq and used a ferrite in the 12v feed with 5 turns
Sorted!
Can you explain the fix for someone decidedly dimmer than you are?! what does that mean in english?!
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