A129 Duo High-Pitched Noise?

[Sergiosmvc]

I saw in other forum that can be ground issues...

 

[m1919]

I was thinking possibly could be that. I'll have to see about changing my grounding point and see if the issue is still there.

 

[RavenManiac]

I recently changed my grounding point from one I custom made to the built-in Honda factory ground and it made no difference.

 

[Nath]

It’s rather “just a noise” from the step-down converter (3-wire kit). The best tool for diagnosis is an osciloscope - then you can try to filter it(small ceramic capacitor, low-pass filter, etc.)

 

[Nigel]

It’s rather “just a noise” from the step-down converter (3-wire kit). The best tool for diagnosis is an osciloscope - then you can try to filter it(small ceramic capacitor, low-pass filter, etc.)

We are talking about sonic noise, not electrical noise. You measure it with a microphone, not an oscilloscope!

 

[Nath]

I thought you’re talking about an acoustic noise from a dashcam and in records. Somebody has stated there isn’t the whinning noise when he use a cigarette socket cable. That sounds to me like an electrical issue...
Do you think the electrical noise is not able to produce a “sonic noise”..?

1. Coils need to be fixed
2. Electrolytic capacitors need a lower caps in paralel to filter higher frequencies
3. Filter the output of the powersupply
4. Different design

 

[Bnedea]

It's just switching noise from the camera's power module.
Power supply output is filtered.

 

[Nigel]

It's just switching noise from the camera's power module.
Power supply output is filtered.

Correct, and the switching frequencies and audibility will vary depending on input voltage to the camera, so I assume the voltage from the hardwire kit is a little different to the voltage from the accessory socket adaptor.

Do you think the electrical noise is not able to produce a “sonic noise”..?

How would it do that? Unless it reaches the speaker!

 

[Nath]

Naturally, it can affect a switching converter. Electromechanical vibration - from inductors, ceramic and electrolytic caps.

Correct, and the switching frequencies will vary depending on input voltage to the camera, so I assume the voltage from the hardwire kit is a little different to the voltage from the accessory socket adaptor.

Sure, could be. But good-old USB has voltage range about 4.5-5.25V, so 3-wire kit is in specs (if it's "filtered"). Then the camera has pretty sh*tty "power module".

It's just switching noise from the camera's power module.
Power supply output is filtered.

Btw: How do you know it's "filtered"? If you see a stable 5V via multimeter, it doesn't necessaraly mean it's rocksolid 5V... (if a multimeter is slow/cheap enough, you'll see 5V even from 12V PWM with 40% duty cycle)

 

[Bnedea]

I know it's filtered because I can see in the pictures above, a coil with a ferite core, and two electrolitic capacitors, near other black bugs soldered on the board.
Maybe it's not filtered enough, that I don't know for sure. But again, the cheap usb cigarette lighter adapter, don't think is better filtered, and with it, the camera is silent.
So to test, I have to do two things:
-lower the voltage of HK3 from 5.2V to 5.0V (a series resistor).
-measure the voltage of the cigarette lighter adapter, with load (camera operating)

 

[NomadTech]

lower the voltage of HK3 from 5.2V to 5.0V (a series resistor)

You need a voltage divider (2 resistors or a potentiometer) not just one.

 

[Nigel]

You need a voltage divider (2 resistors or a potentiometer) not just one.

No, camera takes far too much power for that.
A low voltage drop diode would be a better solution, or the extension cable I suggested earlier.

 

[Bnedea]

Ok, i measured the cigarette lighter adapter:
-without camera -5.07V
-with operating camera 5.04V
I also measured another cigarette lighter adapter with 4.96V, also silent.
I think Nigel is perfectly right, tomorrow I will try a germanium diode on the red wire, I am 95% sure it will mute the high-pitch noise...

 

[Nigel]

germanium diode

Not sure they can carry enough power for the camera? I would use a Schottky diode.

 

[RavenManiac]

This thread is getting interesting. I'm really hoping this works.

 

[RavenManiac]

Ok, i measured the cigarette lighter adapter:
-without camera -5.07V
-with operating camera 5.04V
I also measured another cigarette lighter adapter with 4.96V, also silent.
I think Nigel is perfectly right, tomorrow I will try a germanium diode on the red wire, I am 95% sure it will mute the high-pitch noise...

Did you try the germanium diode?

 

[NomadTech]

Germanium diode has 0.2-0.3 voltage drop. Silicone 0.6-0.7
Also has to be rated for 2A or higher.

 

[RavenManiac]

I just heard back from Viofo regarding the support ticket I submitted. Apparently, its engineering team is working on a new and improved HK3 hardwire kit. They're sending me a test kit to try.

 

[persmash]

I just heard back from Viofo regarding the support ticket I submitted. Apparently, its engineering team is working on a new and improved HK3 hardwire kit. They're sending me a test kit to try.

They've said the same thing to me months ago. The new kit was expected to be ready by the end of April. But It seems that there is a delay on that.

 

[RavenManiac]

They've said the same thing to me months ago. The new kit was expected to be ready by the end of April. But It seems that there is a delay on that.

Out of curiosity, what car are you using the A129 and the hardwire kit in?