imdacrocker
Newbie level 6
I posted some years ago about this project, and am finally coming back to it after 3 years.
I participate in a low budget automotive racing endurance series, and I am looking for a solution to a unique communication problem.
Rather than purchase expensive radio equipment for our car, we simply use a cell phone and headset with mic for communication between our driver and pit. This works great for the most part, but we have run into a few problems.
1. Answering a call in the middle of a race is difficult. Arranging the headset button/mic carefully usually allows for the driver to be able to answer a call, but that is not always the case. The cell phones we purchased basically have no hope of an auto-answer program or feature. We also have found that occasionally the volume buttons are pressed on the phone between pit stops, making it rather difficult to hear. Therefore, I would like a remote cell phone control panel easily available to a driver who is strapped in tightly with a 6 point harness.
2. Certain helmet mounted headsets that the majority of my team have purchased are not quite loud enough in a race car going 120mph with no windows to hear the pit clearly. A signal amplifier has been bench tested proving these headsets can be heard quite well with a little extra amplification.
3. The microphone on the helmet mounted headset appears to be a little too sensitive, causing clipping during the call. Microphone attenuation is needed.
To add to this, I have been inspired by a company that makes a box that intercepts the radio communications and inputs them into the Gopro via a 3.5mm audio cable, as well as mixing it with an external microphone signal. Its can be found here:
**broken link removed**
I have done some research into the headset controls, and it seems that they use a short to ground on the microphone circuit to answer/end calls, and a low resistance signal for volume up/down.
I have successfully tested this amplifier design with my headset:
https://www.circuitbasics.com/build-a-great-sounding-audio-amplifier-with-bass-boost-from-the-lm386/
What I am struggling with is the mixing of the signals of 2 eclectic mics and the call audio from the phone into the Gopro. I have researched microphone preamps, but I am pretty sure both the Gopro and the phone supply voltage to operate the eclectic microphone, and both are looking for a specific resistance value to trigger the device to listen to microphone.
Here is a diagram of the devices and where I would like their signal to go:
broken link removed
The picture says iPhone, but we are using an android now.
So how do I control, distribute and mix all of these signals, while keeping the proper resistance values to trigger the devices?
I participate in a low budget automotive racing endurance series, and I am looking for a solution to a unique communication problem.
Rather than purchase expensive radio equipment for our car, we simply use a cell phone and headset with mic for communication between our driver and pit. This works great for the most part, but we have run into a few problems.
1. Answering a call in the middle of a race is difficult. Arranging the headset button/mic carefully usually allows for the driver to be able to answer a call, but that is not always the case. The cell phones we purchased basically have no hope of an auto-answer program or feature. We also have found that occasionally the volume buttons are pressed on the phone between pit stops, making it rather difficult to hear. Therefore, I would like a remote cell phone control panel easily available to a driver who is strapped in tightly with a 6 point harness.
2. Certain helmet mounted headsets that the majority of my team have purchased are not quite loud enough in a race car going 120mph with no windows to hear the pit clearly. A signal amplifier has been bench tested proving these headsets can be heard quite well with a little extra amplification.
3. The microphone on the helmet mounted headset appears to be a little too sensitive, causing clipping during the call. Microphone attenuation is needed.
To add to this, I have been inspired by a company that makes a box that intercepts the radio communications and inputs them into the Gopro via a 3.5mm audio cable, as well as mixing it with an external microphone signal. Its can be found here:
**broken link removed**
I have done some research into the headset controls, and it seems that they use a short to ground on the microphone circuit to answer/end calls, and a low resistance signal for volume up/down.
I have successfully tested this amplifier design with my headset:
https://www.circuitbasics.com/build-a-great-sounding-audio-amplifier-with-bass-boost-from-the-lm386/
What I am struggling with is the mixing of the signals of 2 eclectic mics and the call audio from the phone into the Gopro. I have researched microphone preamps, but I am pretty sure both the Gopro and the phone supply voltage to operate the eclectic microphone, and both are looking for a specific resistance value to trigger the device to listen to microphone.
Here is a diagram of the devices and where I would like their signal to go:
broken link removed
The picture says iPhone, but we are using an android now.
So how do I control, distribute and mix all of these signals, while keeping the proper resistance values to trigger the devices?
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