yashsingh1/xdaforums huggingface dataset:
[MTCB Hardware Development] Ilkinansr92:
Hi,

I was wondering if someone can help me out.

I have Xtrons TE706PL which comes with this BT module http://www.datasheet4u.com/datasheet-pdf/CSR/BC6130/pdf.php?id=944249

I used a recording app to test the quality of build in mic that i replaced. Below, i attached links to three files that are my recordings. I have the following issue. When the car is parked and i click record button it records the quite and there is almost no audible noise other than a little white noise. Then once i start driving and repeat the process, i hear some type of screech or something. These files are for comparison.

Parked Car: https://vocaroo.com/i/s1HFlwtil6Pw

Highway Driving: https://vocaroo.com/i/s1kSHLiabexf

Driving and stopping: https://vocaroo.com/i/s1pJ4lnMBDLq

P.S

When my car is in ACC mode and radio is on with nothing playing i heard some crackling noise though car speakers, nothing loud. I narrowed it down to WiFi. When there is some data RX or TX i hear that noise. When i disable WiFi its silent.

If anyone has suggestions it would be greatly appreciated.

Thank you.
[MTCB Hardware Development] Ilkinansr92:
TE706PL Circuit

Might help with unit modding
[MTCB Hardware Development] Blueone:
I have a px5 unit with a parrot fc6000t bluetooth module, I also want to do the mic mod because of the interference. I measured al the pins but it is not clear to me which pin is the + of the mic.

I'm measuring the following:

first one is the +, second one is the - (shield)

pin 1 :nothing - nothing

pin2 nothing - 511 Ohm

pin3: nothing - 524ohm

pin4: 1425ohm - 0hm

pin5: 1440ohm - 336ohm

pin6: 1400ohm - 0ohm

pin7: 593ohm - 560ohm

pin8: 1424ohm - 0ohm

pin9: nothing - nothing

pin10 nothing - nothing

To which one should I connect the + of the mic?

I added an extra picture with some red circles, that are the places where I read 0ohm for the mic+, someone have an idea where to connect the mic+ ?
[MTCB Hardware Development] ivorcally:
Microphone amplifier

Hi, I had a similar problem with my Ossuret 8227L based 7" unit. The solution that I came up with was to build a 12V electret microphone amplifier for the external microphone. This makes the signal much stronger than the built-in microphone and it now works very well. To overcome interference noise, I power the microphone using 2xAA batteries and a 2k2 series resistor, instead of dropping down the 12V, but people with a better understanding of electronics than I could probably get the latter to work. It seems that many (all?) of these Chinese head units have this problem and tis might be a universal fix.
[MTCB Hardware Development] timknowlden:
I have the same fault but different board to all photos on here.

Model is Pumpkin AA0495B

I have de-soldered the internal Mic from the front panel and using the external mic via the manafacturers loom.

Pictures of inside the unit here:
[MTCB Hardware Development] Keiuran:
I have the same board as the guy above but with the Parrot Module FC6000T. My internal mic quality started out pretty good but became bad over time with people saying there's static and a distant voice (maybe an amplifier is needed?). I've been searching for a way to fix the issue. Opening the radio up and the internal mic goes through an absolutely insane amount of distance within the device over very small wires. I'm hoping I can splice in new wires at the appropriate locations to cut out all of the noise being generated. Talking with Klyde on Alibaba I acquired a PCB layout of the bluetooth module that I'd like to share so hopefully someone can come up with something.
[MTCB Hardware Development] timknowlden:
I see you have pointed out where the mic connects to the board, im assuming we need to disconnect this here and then when we know which pins on the blutooth module are used for the mic connection we solder an external mic to those?

I would appreciate as you are in contact with klyde if you could get a circuit diagram for my bluetooth module also, GOC RF_210 is printed on the board?
[MTCB Hardware Development] Keiuran:
Honestly it's been a struggle, I'm not really in contact with them so much as pestering them on Alibaba for information and the language barrier is clearly making my requests difficult for them to properly follow up on. There's a good chance I'm gonna need to follow traces on the board using a multimeter to really figure this thing out because I'm not comfortable doing anything without more information. They aren't even providing MIC- and MIC+, just MIC. Though according to another guy in another post the Parrot module has MIC+ on pin 7 and MIC- on pin 6 which at least lines up with the photos I've been provided. At least for my unit it's a complete mess with the mic connecting to a front connector via ribbon cable that connects to the LCD board which then connects via ribbon cable again to the main board before following who knows what path to the microphone connections. And these are like 8 inch ribbon cables and the microphone wires themselves are these incredibly skinny wires running another 8 inches. All together I wouldn't be surprised if the internal microphone connection is running through 4 to 5 feet of basically 24-30 gauge wire. Such awful design.

There's a good chance we have the same mainboard though. PX5-3 Rev 1.4 is what is on my mainboard. Even if they use a different bluetooth module it would have the same pinout to work with the same mainboard.
[MTCB Hardware Development] timknowlden:
Hi Keiuran,

I misread your original post and thought the drawing was of only the bluetooth module, I see now that it is of the PX5-3 Board, comparing the picture between mine and your boards they are identical. Could you please send me the drawing and I can attempt to follow it?
[MTCB Hardware Development] Keiuran:
I haven't been able to get the full PCB Layout document nor the schematics from them despite asking. I asked only for ones relating to the microphone too because I doubt they'd willingly share the entirety of their design documents since others would then be able to make one themselves. If I receive more I'll of course share them here. I'll also share the results of following traces if that turns out to be a successful endeavour.

Talked with them a bit more today and they think my module is possibly broken and to get a new one. I'll try resoldering it and the provided external mic before doing such a thing though.
[MTCB Hardware Development] timknowlden:
It is unlikely to be a faulty module as so many people suffer this issue and as you say it has a hell of a long run from the front panel to the bluetooth chip, I will attempt to solder an external jack to the bluetooth chip soon. I improved mine slightly by using a headset microphone from my playstation and desoldered the internal mic, but probably because the microphone itself is less powerful than the external one provided where as the headset one usually only sits a few inches from your mouth.
[MTCB Hardware Development] Keiuran:
There was a previous poster that said the provided mic had an exceptionally low resistance and improved the mic performance greatly. Another also said they created an amp circuit for their car's OEM microphone and that helped a lot. The units might just not be capable of providing enough current to drive anything with a high resistance, including the internal mic with it's ridiculous long run.
[MTCB Hardware Development] An92:
Sorry, to compensate quickly, you could try to eliminate the internal microphone and use only the external one, since the two of them are connected in parallel ??
[MTCB Hardware Development] timknowlden:
So today I removed the resistor circled in pink that you labelled. I then soldered A microphone jack onto pin 6 and 7 on the BT module. I resoldered my internal mic onto the circuit board as it was before I removed it.

The internal mic works for voice control again and the external mic works well for voice calls. Happy days.
[MTCB Hardware Development] gassnico:
The item that you removed is not a resistor but a capacitance (usually used to remove noise) depending on the board layout for me the MIC+ is on pin 6 and MIC- on pin 7 (the pin 7 is marked as AGND for analog ground)

I encounter mic issue and I search information before to start the modification ! if you have more information or picture of what you did don't hesitate to share!

Did you try mic during drive ? because on my side the sound is good when car is parked !

Best regards
[MTCB Hardware Development] timknowlden:
Hi, yes you are correct those are the two pins to which I soldered an external microphone to. There really isn’t any more to it than what you just explained.
[MTCB Hardware Development] gassnico:
I tried to bypassed serial capacitance without disconnecting the rest of circuit , because I would like to keep external mic connected on the back of headunit but it's not good !

I try to find schematic of board px5-3 to isolate the internal mic of the bluetooth module !

I sent message to klyde team and now I wait and hope that someone will respond to me

If I find something to properly resolve mic issue, Iwill come back her to share !

regards
[MTCB Hardware Development] gassnico:
On this sunday, I tried to solve the mic issue and I discovered that the first analyze is wrong !

Based on previous post I tried to change value of capacitance C50 but the problem was the same.

With my multimeter I search to understood the circuit and discovered that Mic signal arrive on pins of R45 & R42. through R42 the signal continue to C50 then to bluetooth module and through R45 the signal go to motherboard.

I decided to remove R45 To generate a circuit similar to explained one previously by other posts.

please note than my internal head unit mic is disconnected.

I plugged my head unit then test internal audio by a recorder app and no sound as expected.

I placed a call to myself to record audio on my answering machine and with big surprise I received a blank message !

To confirm, I removed R42 and solder back R45 and audio was back internal and bluetooth

My conclusion is that we just need to remove R42 or C50 (connected in serial) to solve our issue I will confirm it tomorrow during drive.

When you remove C50 and connect the external mic on the bluetooth card, the problem is solved but you will use the internal mic only.

You can validate it by knocking the external mic then the internal mic ansd check wich one is really used !
[MTCB Hardware Development] gassnico:
It's a little bit better but it's not clear as expected !

when car is parked, audio is quite good

When I drive with windows closed, audio is correct

If I drive with windows opened , audio is really poor !

I will try to buy a better microphone to check if now the problem don't come from the chineese external mic !
[MTCB Hardware Development] gassnico:
My mic works perfectly ! :)

I purchased a new mic [IMG="Kenwood KCA-MC10"]https://images-na.ssl-images-amazon.com/images/I/31Ji8XZ70yL._AC_SX425_.jpg[/IMG] but it wasn't the solution but has highlighted the origin of issue !

When I connected the new mic the sound was totally disapeared but was back when I moved the jack connector.

In fact in my case the female jack connected to the back of head unit hasn't any spring system to connect the grond and depending of male jack diameter you will haven't any contact or a poor contact (difference between the chineese microphone and the kenwood).

To solve it I added a piece of desoldering wick to force a good contact . Now with the kenwood mic, I have no more issues to place a call or to communicate with head unit everithing is perfect

to resume, I removed R42 and Iadd a piece of desoldering wick at the top of external female jack

[IMG="R42 location"]http://ngassend.free.fr/R42.jpg[/IMG]

[IMG="Desoldering wick"]http://ngassend.free.fr/IMG_20200724_080955.jpg[/IMG]

I hope that it will help some other people to solve their problem

Regards
[MTCB Hardware Development] fredy_pirineos:
I improved the level of my mic built-in with th MTK enginerring app. hardware test and changing mic volumen un normal mode, headset mode and loudspeaker mode, but it is not enough when engine is working. I will try to solder and external mic to the pads of mic built-in. I think that it is also a problem of software filtering because when engine is off, sounds doesn't rattle, the volume is not to high but the communication is steady, but when i start the engine, conversation gets cuts. maybe engine sound is interfering with the mic built-in mic. I will update progressions.
[MTCB Hardware Development] Joaojacinto:
Hello guys.

Let's see if you can explain it

Like you, I also have an Android px5 unit, relatively recent, as I only have it for a year, but the problems have been many and one of them is exactly that, poor quality in the sound of the calls.

People complain that they sometimes have trouble hearing, especially if i'm driving on uneven terrain.

This step and today carefully screams courage and opens my device, but soon notices that it is not the same as any, because I have a Bluetooth rf210 card (I leave photos for clarification). Also notice that my unit come with 2 internal microphones. One on display unit and one on radio unit (CD).

At first I didn't use an external microphone, and it worked more or less, but a few months ago, after some problems, I opened the display module and saw that the positive cable desoldered from the microphone. I tried soldering, but I couldn't.

Then I started using a microphone (which come with a unit) and still complains that they could not hear me imperceptibly, when a totally external path on uneven terrain.

I decided to put in a quality external microphone, Linhuipad ( https://www.amazon.co.uk/LINHUIPAD/...1337031&field-lbr_brands_browse-bin=LINHUIPAD ), but it ended up getting worse.

Just opened an external radio unit (CD), unsold the internal microphone, soldering an external microphone unit there.

It has improved considerably, but not yet with the quality result.

Since I don't understand the subject, I ask for help to improve the sound quality

thanks in advance

(Google translate)

João Jacinto
[MTCB Hardware Development] Gagge89:
Good morning,

Does anyone with an Eonon style GA5153F (or similar) have photos and an exact description of how they improved their mic audio? Which pin to disconnect, if there is an internal microphone, is it directly soldered to the board or if it is connected with a cable, etc... because before disassembling the whole car and not having much time to do it (since I often use it for work or my wife uses it) I have to be as safe as possible in order to disassemble, be sure of what to remove or put and reassemble :) Thanks
[MTCB Hardware Development] dadd10:
Parrot Mic

Hi dsa8310

What Parrot mic are you using?, I have tried the 3100 which has the right size jack plug but is mono and that will not work, also bought a 9100 dual mic and connected via a 2.5mm to 3.5mm adapter but that does not work either. The mic that came with my unit works but is still not that good after doing the separation.

I have the Joying head unit.

Regards

Dadd10
[MTCB Hardware Development] halloj:
I've have the same setup as dsa8310 and I'm using the Parrot 3100 mic. Works perfect. It's modified and connected to HU the same way as dsa8310.
[MTCB Hardware Development] Piaband:
All,

I have a joying 1024x600, rk3188 quad core unit. I opened it up to do the Mic mod like it has been detailed here. But my board looks different than the ones I have seen posted here. I don't have any numbers like c32 or c102. Should I just start using my ohm meter to test connectivity? I don't know where to go from here.
[MTCB Hardware Development] halloj:
Look for the screen print on the other side of the BT-board, should say mic+. Or assume it's the fourth pin from the left, not right as on other boards, viewed from the inside of the MB and beep it with your ohm-meter. Sometimes it's a cap, resistor or just a short. The board looks exactly the same as on my KLD, except that yours is fitted 180 degrees

around.
[MTCB Hardware Development] dadd10:
Hi halloj

Is your 3100 mic hard wired onto the BT module or is it connected via a female socket which is then hard wired to the BT module?

Regards

dadd10
[MTCB Hardware Development] halloj:
I've done it the way I recommend. Shielded wire from a socket attached to the chassis. Shield attached to the socket but left

open in the BT end. I.e you get ground through the socket which is grounded in the chassis. I'm using a "monosocket", since the mic is mono.
[MTCB Hardware Development] dadd10:
Thanks halloj, I will try that out when I get some time, at least I now know that I do not have to hard wire the mic direct to the BT module to get it to work.

Regards

dadd10
[MTCB Hardware Development] halloj:
You're welcome.

Should have been: I've done it the way I recommend.
[MTCB Hardware Development] Tabs78:
Hi.

I have nobody can do the hardware mod and i tried the external mic.

What can i do?

Exist a module or way to use an external bt handfree like call mic and car speaker like call speaker ?

I'm disperate

Inviato dal mio SM-G920F utilizzando Tapatalk
[MTCB Hardware Development] Zorba2pi:
I have a new Car Joying unit without screen printing on the main PCB. I've tried to beep all the resistors and caps in the area but haven't been able to get any to beep. I also tried following the traces, but either I am dumb (possible) or the PCB has more than two layers.

Is it possible to just cut the pin going from the BT card into the main PCB? Removing the jumper is basically disconnecting the BT Card from the main board, correct? So could we skip that set and just cut the pin?

Thanks,
[MTCB Hardware Development] halloj:
That's the same thing. Remove the cap/res/short or cut the right pin will do.
[MTCB Hardware Development] Zorba2pi:
So I cut and desoldered the pin from the Blue Tooth board. I then used a shielded microphone cable from Radioshack. I then soldered the signal wire back the original microphone pin on the blue tooth board (4th from the back) and soldered the shielding to the SGND pin on the blue tooth board (5th from the back).

This completely eliminated all noise on the external microphone and the internal microphone still works for Android. I personally think cutting the pin is much easier than desoldering a flush mount Cap/Resister on the main board.

But I still have the problem of a really bad echo on the other end. Basically the person on the other end of the phone can hear themselves with a half second delay. Is there any way to fix this?
[MTCB Hardware Development] Piaband:
I did the exact same thing and no longer have any audio coming through the external microphones. Neither the one I wired in directly or the original external microphone. I will post pictures later, but anyone have any ideas where I could've gone wrong?

Cut pin 4. Wired the positive side of the Mic to the cut pin 4, and the ground of the Mic to pin 5. Put it all back together. Now I have no outgoing mic audio on my unit. No internal audio either it seems though I'm not completely sure about that.
[MTCB Hardware Development] Piaband:
Ok, I need some help with this guys.

I have a Joying 1024x600 RK3188 unit.

I opened up the unit to discover that I had no data printed on the blue breadboard. I could not locate c32 or c102 for this reason. Instead, I cut pin 4 on the bluetooth module, then wired a mono microphone jack directly to the bluetooth module. I put it all back together and my microphone no longer works. I tested my new microphone external jack and the OEM microphone external jack. Neither works now. I've tested continuity and I have a good connection between the bluetooth module and my new external microphone jack. I dont have any shorts that I can find. What did I do wrong here?

Also, I'm using the external microphone that came with the Joying unit. It is a stereo microphone (3 sections). I dont think that should be a problem with my mono mic jack, but maybe it is? Could that be the problem?
[MTCB Hardware Development] Zorba2pi:
To test the internal mic, try google voice search. Messing with the BT card shouldn't have messed it up. If you disconnected the ribbon cables make sure you reconnected them straight and go the sliders all the way in. When I put mine back together the screen wouldn't come on because I had a ribbon cable out of alignment.

The way you did your wiring looks just like mine. I am guessing the stereo plug going into a mono receptacle is the problem. It could work just fine, but I am guessing that the positive wire on the mic is only connected to one of the 3 bands (probably the mic band), so if the contact in the monoplug is lining up with one of the other bands, you wouldn't actually get a signal. I would try to find a mic with a mono plug on it to try, like an old computer mic. You could also get another cable like the one you soldered onto your board and try the mic through that cable on a PC or stereo.
[MTCB Hardware Development] m00n61:
Pinout of the GOC-I2U-705A BT daughterboard

Anybody has it?

I have an Eonon GA2114 (rk3188, 800*480) unit. The MB is Klyde and the BT board is the Goodcom GOC-I2U-705A. There is no pinout printed.

I could not find the pin connecting to the internal mic but I traced the external mic connection and found where it connects to the BT board.

Cut the pin and and soldered a shielded cable. BT call quality is better (mainly because by disconnecting the original external mic connection I eliminated a source of noise) but the internal mic still works with BT? I have uploaded a picture of my setup.

Can anyone provide a pinout of this BT board?
[MTCB Hardware Development] halloj:
Zorba above might be right. Could also be that the mic you have need a voltage to work, hence the stereo connector. Try a mic with only mono connector.

---------- Post added at 08:42 AM ---------- Previous post was at 08:33 AM ----------

It looks like you're connected to the wrong pin, compared to my Klyde. Have look at the original description for comparison.
[MTCB Hardware Development] m00n61:
Is your BT board also a GOC-I2U-705A? Can you post a picture of the pin layout?

These manufacturers use many different BT boards as well as MB so the fact that it looks different is pretty much irrelevant. No picture of a BT board on this thread matches mine. The pin I have used is where the original external mic was connected. I'd say it's a safer bet than 4th pin on the left :)
[MTCB Hardware Development] Zorba2pi:
I assume you made sure that the new external mic works? If so, you could try to beep all of the pins on the BT card with the pin for the external mic. If they are jumperred together on the BT card you should be able to get continuity between the pins.
[MTCB Hardware Development] m00n61:
Yes, I checked the external mic and it works OK. Already tried your suggestion, no luck. Probably connected through a capacitor. I did a little more research, here are the findings.

1. The BT board is similar to the others, only it is soldered reversed - when compared to what is on this thread and the similar thread on 4pda. That is, the component side is towards the outside of the HU. Maybe because the MB design has changed.

2. As far as I can tell, pin out is the same (1 and 2 are left and right out, 3,5 and 7 are GND, 4 is external MIC) if you start counting from the other side :)

3. There seems to be some capacitors between the internal mic and the BT board so could not check for continuity. I am not so sure about the internal mic pins though, because of its position.

4. BT board pin 4 completely removed-internal mic still works for BT calls. The good thing is that now call quality got better. This is kinda funny considering that one of the reasons I gave up my old AN21U was the possibility to connect an external mic for BT calls.

Since DC continuity is irrelevant I guess I will build a small signal generator and use an old headphone for tracking. The other option being to use an oscilloscope but I don't have one available.
[MTCB Hardware Development] mixmaster57:
Hello,

I have the same device and i have the same probleme lol.

Did you solve your microphone probleme? Mine the level is too low

Thanks for the help