helmet bluetooth PTT switch to be connected to Tk8102

[Rubenctc15]

i have one of this i like to connect it to a Kenwood TK8102 with an external PTT (the BT-PTT not working so i like to have a wired PTT Botton) the radio is on my motorcycle. i have already make it with a plastic box the 2.5 and the 3.5 connectors, i used a 8 pin phone conector to connected from radio, using web schematics i used pin 3, 4 and 7 out of the radio to connect the bluetooth so far i was able to make the ptt to connect for TX but no sound from the mic. and other radios tx and i have no sound coming out of the head set. any advice? or schematics? i will Appreciate any direction.

 

[ramal121]

Pins 3 and 4 is correct for PTT input. Pin 7 for microphone is not correct. Use pin 5 ground and pin 6 mic in.

For receive you'll have to tap into the external speaker jack on the back of the radio.

 

[Rubenctc15]

thanks for the advice, i tried your advice, i have done some right and some wrong things are as follows, the tk8102 has a PTT TX and RX, before your advice i had no sound out of the BT head set speakers, as well as no sound been TX from the bt Head set mic on to the radio, PTT apparently was engaging fine, now after your suggestion, some progress, i make my set up diagram is attached bellow. what i got so far is this.
i use another radio to tx tk8102 it RX the transmission & sends the audio to the BT to the head set speakers sounds fantastic, then i use the BT head set PTT or the PTT button and the BT device PTT engages the tk8102 TX the PTT normal the other radios RX the Signal but there is no mic sound. please correct in what i am doing wrong. apparently speakers and PTT are Ok but the MIC is not sending sound.

 

[ramal121]

Per your diagram you are using speaker minus as ground. This is true for this model radio but realize not all radios have a ground on one side of the speaker and you can damage something when trying to use it as such.

Now not knowing anything about your headset system, some use balanced audio inputs and outputs to make it compatible with more radio types. If this is the case you'll need to add a ground line that would just be used for yhe mic in line.

Do you have a diagram for what all the functions are in those radio interface plugs?

 

[Rubenctc15]

No i do not, but you are right this is a bt divice compatible with baofang, kenwood, hys and others like it now you are sugesting me to add a separed ground line to number 4 out of the mic?
I know it will be my responsability of any damege to my equipment. I have no schematics of the interface wich i realy do not know the pins are correct i am going for the external mic connector diagram from internet the picture has the way i conected them tge first time and did not work until i make tge changes

 

[EWC_BDN]

A TK8102 will have 0V on the mic line. it requires a bias to work. The normal Kenwood mics use the SB(12v) to power all the mic's backlight and provide a bias to the mic. It isn't straight 12v to the mic. there is a resistor and a regulator. What i've done to work with this is use a 4.7k resistor from 12V to mic and that's worked for hooking up aviation headsets to radios in Ag planes. You can easily blow the radio fuse though doing this stuff. so proceed with caution. A motorola radio is a bit easier to do this with IMO.

 

[krokus]

The adapter with this package could be useful.

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