motorola hf 850 bluetooth kit

Printed From: the12volt.com
Forum Name: Cellular and Communications
Forum Discription: Cell Phones, Hands Free Kits, Bluetooth, Two Way Radios, CBs, Pagers, Wireless Internet, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=112611
Printed Date: May 02, 2025 at 10:54 PM

Topic: motorola hf 850 bluetooth kit

Posted By: ghanaboy
Subject: motorola hf 850 bluetooth kit
Date Posted: March 23, 2009 at 10:15 PM

Hi There

I have a Motorola HF 850 Bluetooth kit i'm trying to install without luck

I have the Bluetooth system working correctly

When i tried to wire in the Mute Function i had a problem

I wired up a relay as Stereo has no mute function.

86 12volt Ing Feed

85 Orange Bluetooth wire

87a one side of Stereo power wire

30 otherside of Stereo power wire.

This cuts off the stereo for only a few seconds then its back on again.

How do i wire it so that the stereo stays off for the entire call

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Stevo

Replies:

Posted By: i am an idiot
Date Posted: March 24, 2009 at 2:14 AM

The problem is that the bluetooth module does not have enough current capacity to ground the relay. There is a simple fix for this. Purchase One of these, and connect it as follows. The ground output wire from the bluetooth module connects to the base of the transistor. With the transistor facing you so you can read the numbers, and the legs facing down, the base is the left leg. The collector which is the middle leg is to be connected to ground. The right leg is connected to the coil of the relay. The module will turn the transistor on and the transistor will provide enough current to keep the relay energized through the entire call.

Posted By: i am an idiot
Date Posted: March 24, 2009 at 2:22 AM

Posted By: ghanaboy
Date Posted: March 24, 2009 at 3:51 AM

Thanks

Will See if i can get one tomorrow

So i would Wire it into 85 and 86 of the Relay

Thanks Again

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Stevo

Posted By: i am an idiot
Date Posted: March 25, 2009 at 7:18 PM

The drawing depicts 86 as ground and 85 as power. Technically 85 should be ground. and 86 should have positive voltage.

Posted By: ghanaboy
Date Posted: March 25, 2009 at 9:34 PM

Thanks

No Luck finding these in OZ but have 2 coming from US next week.

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Stevo

Posted By: i am an idiot
Date Posted: March 26, 2009 at 6:29 PM

I did not notice your location. Are NTE parts available there? NTE332 or a 2N6491 would do just as good of a job.

Posted By: sparkie
Date Posted: April 02, 2009 at 7:35 PM

Are you sure that the orange wire is the mute wire. The Motorola pieces I have used have a yellow wire which goes to ground while in use.

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sparky

Posted By: ghanaboy
Date Posted: April 02, 2009 at 7:45 PM

https://4x4icon.com/offroad/hands_free/handsfree_wiring_diagram.gif

This is how i Wired it

It Stated that the Yellow was not Used.

Are you saying that the Yellow Wire should be USed over the Orange.

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Stevo