Radio interferance

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Stovies
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Radio interferance

Post by Stovies »

I bought a couple of USB chargers that fit in the cigarette holder but when I use them even without anything plugged in to them then I get a very bad loss of reception from the radio.
any ideas????
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CovKid
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Re: Radio interferance

Post by CovKid »

Who made them? If generic (particularly pound shop ones), theres your answer :wink:

Bear in mind they drop 12v to 5v and the interference suppresion and smoothing can be non-existent in some.
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bigbadbob76
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Re: Radio interferance

Post by bigbadbob76 »

yeah, probably lack of suppression in the 12v to 5v regulator, as yer man Covkid says.
Worth checking your aerial connections too, dirty aeirial connections can pick up interference.
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AngeloEvs
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Re: Radio interferance

Post by AngeloEvs »

Most 12v USB devices are switch mode and run at high frequency, hence the interference, these are compact and do not require large heatsinks like a conventional 12v to 5v power supplies requires. I built one and it gets hot running my dash cam and sat nav but I do not get the interference.

A lot of dash cams also cause interference for the same reason where the 12v to 5v switch mode circuit is in the 12v cigar type plug.
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Stovies
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Re: Radio interferance

Post by Stovies »

I have bought 3 and the ones in my other cars work fine and don't interfere with the radio so I think it could be the way its wire up behind the dash or the radio itself
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Mocki
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Re: Radio interferance

Post by Mocki »

its alot to do with the cig socket in a t25 being fed from the same supply as the radio,
this is not the case with more modern cars
try a different feed point or moving the radio power off onto a dufferent power supply point on the fuse box

cheap china tat often has no suppression, certain led arrays are horrible to RF signals
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itchyfeet
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Re: Radio interferance

Post by itchyfeet »

I spent ages trying to find the reason my car radio didn't work only to find it was one of these crappy usb ciggy adapters, I assumed it was engine noise because it only happened when driving and only in low signal areas, ciggy lighter comes in with ignition
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CovKid
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Re: Radio interferance

Post by CovKid »

I'm inclined to wonder of a suppressive capacitor close to radio or back of ciggy socket might help ;)

Possible: https://www.ebay.co.uk/itm/10A-Noise-Su ... Swx2dYG1NG" onclick="window.open(this.href);return false;
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