We have a new van that we have been taking on a few shakedowns to test everything out. Most all is going well but one thing that has been a pain has been a constant buzzing in all 4 speakers. I thought it might just be poor speakers, but this weekend we went on another trip and whilst testing the different settings on the fridge switched it over to battery and the buzzing went, it also seemed to be the same for gas. So I'm now guessing it has something to do with being on mains power.
has anyone else had a similar issue and/or any suggestions on how to correct?
RFI . Can speaker wires be routed away ? Can they be twisted ? May require an RFI filter ? Or better elect shielding .. New talk to dealer . There's fixes out there ..
-- Edited by Aus-Kiwi on Monday 26th of September 2016 11:02:26 PM
You can not stop interference at the end, you have to stop it at the source. The buzz is 50Hz or 100Hz drifting back the power line from the fridge. This is dependent on what sort of thing is inside the fridge the thickness of wire used etc. Filters may help but its all trial and error stuff. Rob
There is a filter you can buy from a car accessory shop that fits on the DC input to the radio. Not very cheap but effective, notches out the annoying frequency.
Good luck with that
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Ex RAAF, now retired. EX Electrician/Teacher.
Homebase is Murray Bridge Tourist Park (in a cabin). New Horse.. 2020 Ford Everest Titanium, Jayco swan for touring.
An earth covering can shield . Why twisting wires can help . Another method is to lie speakers wire saddled to body Using sheathed cable helps . But only earth at one end or it becomes a conduit for RFI ..
Finding the real cause can be difficult as can the best method correction, especially if you have to buy & try!!
AS above , by RRobor ,it will be a trail & error job
But as the van is new, I too would advise going back to the maker /dealer, IF the radio was supplied & installed by them.
Since the noise does not exist when the fridge is on 12V that seems to rule out the fridge [inverter] as the source, what is brand & model of fridge??
It is quite possible that it is due to nonshielded speaker cables being in close proximity to the current carrying mains wiring, as suggested by Aus Kiwi
50 or 100Hz hum is not RF. It is normally a slight clipping of the AC due to the load. This seldom travels through the air but is conducted through the power leads. To test that you could try using an extension cable from another source into your van for the amplifier. As the post above states, if some idiot ran the speaker leads hard against the power leads you could get capacitance coupling otherwise its not likely. The fixes usually consist of choke coils in the line with capacitors as filters, but as the noise is unplanned, its hard to determine how to tune something to filter it out. Rob
We have a new van that we have been taking on a few shakedowns to test everything out.
Steve
Steve, obviously you have a warranty issue. before you go to make the claim you need to isolate the problem. This is easy to do. Switch every thing off (or pull the fuse) until you have only one thing powered from 12 V and you are still experiencing the interference. Leave the van in that state and then present it to your agent.
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PeterD Nissan Navara D23 diesel auto, Spaceland pop-top Retired radio and electronics technician. NSW Central Coast.
