Static-like distortion on dashcam ....... in car only

[gamesfrager]

Hi,
OK, I'll try to a site to part it on. (The .mp3 file I have is only 157kbs; but I can convert it to any audio format.)
Thanks again,
.... john
P.S. OK. Try this https://youtu.be/FkfgHnu2oVA
By the way, I never receive notification of my posts.

When you said static in your original post, I thought electricity static. This is certainly a vibration/mechanical noise.
I would open up the camera housing carefully and inspect any loose wires and secure any flapping wires or components.

 

[shinnen]

I found a couple of zcat2035-0930 ferrite cores on some other cables I have. Could putting them on the cable running from the cigarette lighter to the dashcam help with my interference problem?
..... john

 

[Nigel]

I found a couple of zcat2035-0930 ferrite cores on some other cables I have. Could putting them on the cable running from the cigarette lighter to the dashcam help with my interference problem?
..... john

It will not do any harm...

 

[shinnen]

Hi Nigel,
Is there any particular spot on the cable which is better; close to the connections, close together???
..... john

 

[Nigel]

They are normally placed about 10 cm from the camera end of the cable, Probably a good place for protecting the camera from noise.

 

[Nigel]

close together???

I think you only need one, but you could try one each end, 10 to 15cm back.

 

[shinnen]

Hi Nigel,
Well, I tried the cores, and they "might" have made a small difference, but I'm not sure. I then took the camera apart and looked for any signs of loose wires, etc.; and didn't see anything obviously wrong. I did notice however, that the USB (output/power) port is right beside the speaker. I'm not sure if that is poor design or not. I also tried holding the unit close to several machines (drier, washer), radio amp, fuse panel, florescent and incandescent lights and didn't notice any audio distortion. So ..... I'm stumped.
Thanks again for your (and everyone elses) help.
.... john

 

[Nigel]

Well, I tried the cores, and they "might" have made a small difference,

Sometimes these things do help, it was worth trying, but normally they are used to prevent the dashcam causing interference on your car radio, and they can work well for that.

 

[Michael23]

Hi John,
Further to what has been suggested.....
Just thinking "as an old electrician/technician" here, but since you are able to disassemble the dash cam, I would grab a magnifying glass & look at every solder joint very carefully.

I'm thinking a dry solder joint may be the cause.
A dry solder joint will look a bit dull & crackled.....possibly.

If you can power it up with with it apart, use a wooden match stick or similar & just move all the wired connections around a little bit.
I'd also very carefully test (wiggle) all the larger components for dry joints.....eg: capacitors etc., etc.
Check both sides of the PCBoard for dry joints.

Do this in the car not on the work bench.

You are looking for any wire or component that moves...when it shouldn't.

Just take your time & do a thorough investigation.

Chasing these faults can be tricky to nail down.

Can't think of anything else, so good luck.

 

[shinnen]

Hi Michael,
Thanks for the suggestions. In previous posts I've mentioned that I have rapped the unit with a screwdriver, many times, and never noticed any distortion. Wouldn't you think that this suggests that the source of the problem is not caused by solder joints, capacitors, etc.?
..... john

 

[Michael23]

Hi,

Did you use the magnifying glass & check all the solder joints & carefully move the larger items for any loose solder joints or even a broken PCB trace/track?
Well, If nothing seems to be loose or wires broken or bad solder joints, then the next thing to check is the car's systems....eg: radio connections, speaker connections, Air Con & anything else that is factory installed or any accessory by you.

Best way to check each individually is to pull each fuse.....one at a time & test the dashcam.

Hands on fault finding in a car is damn difficult.....trying to do so using this medium is nuts.

Maybe an idea to see if your friendly Auto Electrician can suggest something...errr find the culprit?

It really sounds like either a bad earth connection or even a bad +ve one in the car.

Don't know what else to suggest.

 

[shinnen]

Hi again,
I think I have found the source of the sound distortion on this device. A couple of people here suggested that there might be something loose in it, and when I shook it, it did indeed souned like something was loose. Upon opening it, I discovered that the screen was pressing again the mother board, so I gooped the screen to the board, and now I don't here any distortion. Problems solved, I hope.
Thank you all for your help on this.
.... john

 

[Michael23]

Hi John,
Glad to be of assistance in your deducing the "problem."

A suggestion for you...

I find that double sided foam mounting tape comes in mighty handy at times.
Comes in a variety of widths.
Any hardware store should have it.

If you wanted a thicker variety, try a model shop that sells radio controlled accessories.
Servo Mounting tape has a much thicker foam centre.

Stay safe.