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So I posted this over in the HMMWV page in the " What have you done to your HMMWV today/lately " thread, but it's probably more fitting for it to be in here as it's radio related equipment.
I wanted to be able to use a GMRS radio in the HMMWV while moving, as I do off road driving and sometimes help recover stuck vehicles out on the trails. The radios I have just aren't loud enough for me to hear, and there is so much noise in the truck nobody else can understand me when driving.
I finally got around to thinking about possible solutions, and saw on facecrook where someone is turning LS-671 units into bluetooth speakers. Looking at some pages, I figured it wouldn't be too hard to wire a stock unit to work with an external radio.
So here is the website that gave me the most information about the LS-671, including ( and especially important) the wiring diagram and connector pinout.
I'm not going to link all of their images here as they show each function operating, but here is the overall diagram
I ordered just a cut off end from what was listed as a CX-13292 cable. I used a multimeter to figure out what wire went to which pin, and apparently the cable end I received was for a different application or the opposite end from the LS-671 because it was missing a wire for pin J the Push To Talk (PTT) circuit. A little soldering iron and random wire later, I had all the wires I needed.
The specific radio I'm using is a Baofeng. Cheap, but functional and if I destroy it I won't be terribly upset. It uses a Kenwood type connector (commonly called a "K1" connector) for it's external audio, which is basically just a 2.5mm and 3.5mm plug. Cheap enough to buy a 2.5mm to 3.5mm adapter cable and cut it in half to get both cable ends needed.
Here is the diagram of what pins do what job, and what pins they go to on the connector:
(image borrowed from https://www.wildtalk.com/knowledge-base/kenwood-2-pin-wiring-data/)
I don't normally work with wires this small, so don't have the correct connectors for splicing them. For testing purposes I cobbled together a lot of junk that looks bad, but is good enough for a test. 18V milwaukee battery provided the power needed (reads at 20 volts full charge)
With everything wired up and my son walking around outside in the yard, everything functioned how it was supposed to. The only thing to get used to about it is the H250 is "noise cancelling" to the point where you are practically eating the mic portion in order to be heard on the other end. Multiple websites I visited mentioned that in order to use it it has to be touching your lip when talking.
The loudspeaker portion of it was extremely loud when turned up, so I have no doubts that I will be able to hear it when driving.
I wanted to be able to use a GMRS radio in the HMMWV while moving, as I do off road driving and sometimes help recover stuck vehicles out on the trails. The radios I have just aren't loud enough for me to hear, and there is so much noise in the truck nobody else can understand me when driving.
I finally got around to thinking about possible solutions, and saw on facecrook where someone is turning LS-671 units into bluetooth speakers. Looking at some pages, I figured it wouldn't be too hard to wire a stock unit to work with an external radio.
So here is the website that gave me the most information about the LS-671, including ( and especially important) the wiring diagram and connector pinout.
I'm not going to link all of their images here as they show each function operating, but here is the overall diagram
I ordered just a cut off end from what was listed as a CX-13292 cable. I used a multimeter to figure out what wire went to which pin, and apparently the cable end I received was for a different application or the opposite end from the LS-671 because it was missing a wire for pin J the Push To Talk (PTT) circuit. A little soldering iron and random wire later, I had all the wires I needed.
The specific radio I'm using is a Baofeng. Cheap, but functional and if I destroy it I won't be terribly upset. It uses a Kenwood type connector (commonly called a "K1" connector) for it's external audio, which is basically just a 2.5mm and 3.5mm plug. Cheap enough to buy a 2.5mm to 3.5mm adapter cable and cut it in half to get both cable ends needed.
Here is the diagram of what pins do what job, and what pins they go to on the connector:
(image borrowed from https://www.wildtalk.com/knowledge-base/kenwood-2-pin-wiring-data/)
I don't normally work with wires this small, so don't have the correct connectors for splicing them. For testing purposes I cobbled together a lot of junk that looks bad, but is good enough for a test. 18V milwaukee battery provided the power needed (reads at 20 volts full charge)
With everything wired up and my son walking around outside in the yard, everything functioned how it was supposed to. The only thing to get used to about it is the H250 is "noise cancelling" to the point where you are practically eating the mic portion in order to be heard on the other end. Multiple websites I visited mentioned that in order to use it it has to be touching your lip when talking.
The loudspeaker portion of it was extremely loud when turned up, so I have no doubts that I will be able to hear it when driving.
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