Electric Brake Booster and Blue Tooth.

Mudeblue

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Setting the stage: I installed an electric brake booster in my 65 SF and a RediRad AM Adapter along with Bluetooth as part of my restoration. Both work fine BUT incompatible. When I am using the blue tooth and I tap the brakes, the blue tooth on my i-phone quits working and I have to reconnect. I am not an electronics expert or a physicist but my expertise in finance tells me that the electric booster must send out an electric magnetic field the conflicts with the the field created by my i-phone. Any thoughts of wisdom someone can share?
 
Electric brake booster? That is current model Ford technology. Not sure how yours works but on a modern Ford you have a brake pedal simulator with a force sensor, and an angle sensor. There is an ABS module and HCU that do all the braking.

The simulator is connected to a pushrod and a small isolated chamber of brake fluid. The ABS module reads the force and angle sensors and controls the force applied to the wheels by the HCU.

That seems extremely complicated and unnecessary for a classic car. There must be some kind of electronic interference as you state. Bluetooth devices are required to accept signals, even those that cause undesired operation. Without a theory of operation on the particular EBB you have, this is speculation.
 
Setting the stage: I installed an electric brake booster in my 65 SF and a RediRad AM Adapter along with Bluetooth as part of my restoration. Both work fine BUT incompatible. When I am using the blue tooth and I tap the brakes, the blue tooth on my i-phone quits working and I have to reconnect. I am not an electronics expert or a physicist but my expertise in finance tells me that the electric booster must send out an electric magnetic field the conflicts with the the field created by my i-phone. Any thoughts of wisdom someone can share?
I've looked at a couple of these systems that the street rod guys are using. Looks like there's an aftermarket version with a electric motor that drives a hydraulic pump and there's a Tesla/Honda based system that works mechanically with the motor driving a gear that helps push the MC. I'm curious which one you have.... The Tesla version looks real simple.

Either one has a DC motor that probably has a pretty big electric draw when it starts. So... While I'm no expert here.... I think I would look at how the power supply for the motor runs and make sure it doesn't share any connections with the radio. If this is an aftermarket setup, I'd call the company and ask for recommendations.

You're probably going to have to come up with some shielding for the electric motor... and maybe look at putting a capacitor in the wiring. Not my field of expertise so someone else may have an idea here.

In a coincidence, I just read the other day about the manufacturers phasing out AM radios because of all the electrical interference from the new electric cars.
 
Electric brake booster? That is current model Ford technology. Not sure how yours works but on a modern Ford you have a brake pedal simulator with a force sensor, and an angle sensor. There is an ABS module and HCU that do all the braking.

The simulator is connected to a pushrod and a small isolated chamber of brake fluid. The ABS module reads the force and angle sensors and controls the force applied to the wheels by the HCU.

That seems extremely complicated and unnecessary for a classic car. There must be some kind of electronic interference as you state. Bluetooth devices are required to accept signals, even those that cause undesired operation. Without a theory of operation on the particular EBB you have, this is speculation.
"That seems extremely complicated and unnecessary for a classic car." Actually when it comes to restoring a classic car, that whole statement applies but it sure cleaned things up under the hood and not having power brakes it sure was an improvement and then there is the installation of disc brakes all around which also could be argued was not necessary! Given the market value of the car vs. the cost of restoration, somebody should have hit be along side of the head when I started this venture! What's the old cliche, "I wish I knew then what I know now" but in reality I would probably do it all over again. I went from feeling like the owner to now feeling like the caretaker!
 
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I've looked at a couple of these systems that the street rod guys are using. Looks like there's an aftermarket version with a electric motor that drives a hydraulic pump and there's a Tesla/Honda based system that works mechanically with the motor driving a gear that helps push the MC. I'm curious which one you have.... The Tesla version looks real simple.

Either one has a DC motor that probably has a pretty big electric draw when it starts. So... While I'm no expert here.... I think I would look at how the power supply for the motor runs and make sure it doesn't share any connections with the radio. If this is an aftermarket setup, I'd call the company and ask for recommendations.

You're probably going to have to come up with some shielding for the electric motor... and maybe look at putting a capacitor in the wiring. Not my field of expertise so someone else may have an idea here.

In a coincidence, I just read the other day about the manufacturers phasing out AM radios because of all the electrical interference from the new electric cars.
If it can't be readily identified and rectified, the easiest solution would be to disconnect the AM Adapter from the blue tooth and plug that directly into the old i-phone which I am using. My GTO is set up that way and isn't as convenient by it works, Thanks for the input.
 
Disc brakes are not unnecessary on a classic car, but they are appreciated. My first hand experience with EBB brakes is that they are great until they are not.

You also offered no explanation of how the part you installed works, but you answered your own question.
 
Disc brakes are not unnecessary on a classic car, but they are appreciated. My first hand experience with EBB brakes is that they are great until they are not.

You also offered no explanation of how the part you installed works, but you answered your own question.
Not sure what part you refer? They all work good except the blue tooth until I step on the brakes.
 
@Mudeblue it would help if you provide some pics of your electric brake booster install. Maybe a brand and part number even. Those might aid in finding a solution for your magnetic interference.

In a coincidence, I just read the other day about the manufacturers phasing out AM radios because of all the electrical interference from the new electric cars.
The things you learn from the RockAuto newsletter trivia question haha.
 
I've looked at a couple of these systems that the street rod guys are using. Looks like there's an aftermarket version with a electric motor that drives a hydraulic pump and there's a Tesla/Honda based system that works mechanically with the motor driving a gear that helps push the MC. I'm curious which one you have.... The Tesla version looks real simple.

Either one has a DC motor that probably has a pretty big electric draw when it starts. So... While I'm no expert here.... I think I would look at how the power supply for the motor runs and make sure it doesn't share any connections with the radio. If this is an aftermarket setup, I'd call the company and ask for recommendations.

You're probably going to have to come up with some shielding for the electric motor... and maybe look at putting a capacitor in the wiring. Not my field of expertise so someone else may have an idea here.

In a coincidence, I just read the other day about the manufacturers phasing out AM radios because of all the electrical interference from the new electric cars.
What @Big_John says may be true.
DC motors can create a mess on power lines (large current draw and distortion of the power form - with alternators onboard, the ‘DC power bus’ is already messy with spikes and distortions due to the alternator rectifying the alternating current to kinda DC).
I worked with heavy dynamic loads in radar and we installed huge capacitors to smooth out the DC power to the radar antenna as well as prevent spikes running back to the generator control system in the aircraft. The generator control unit in that situation was actually tripping offline before the conditioning system was added.

My suspicion is that when the DC Brake booster motor is turning on, it’s distorting the power and/or dropping the voltage to a point that is causing issues with the Bluetooth transmitter.

Unfortunately, solving this may become quite a task.

A different solution like referenced to connect the phone to the audio system with a cable may be the most pragmatic way, without looking at the dc Brake booster’s behavior or even modeling the entire circuit in a simulation program,similar to PSpice.
 
Since you issue involves a disconnection and not just noise in your music I'm not really sure but I'm guessing noisy power is the problem. If you have your phone plugged in (lighter/other 12v) try unplugging it and just use phone battery. Does that fix it? If not then you need to try powering the entire redirad system with an external 12v battery (drill, another car battery) or wall wart that puts out 12v. If that fixes it you need an isolated power supply. They are not that common. It will take a while from china. There are plenty of small isolated DC-DC 12v isolated power supplies but they usually are only outputting milliamps...not enough for your needs. If you search ground loops and power supplies especially related to digital signal processors, you will see some familiar issues. Why don't you call Redirad. Old cars have all kinds of noise, they probably have heard of it.

I bought the second one for my Bluetooth project but have not used it yet - avoiding 12v noise is the goal.

DC-DC Isolated Step-Down Power Suply Module 12V-90V to 9V 12V 19V 24V 4A 3A | eBay

https://www.aliexpress.us/item/3256...2i3EP1w&gatewayAdapt=glo2usa&_randl_shipto=US
 
Also I wanted to try one of these optocoupler relays. They should work. Trigger would be 12v ignition switched. But I havnt thought it out yet. These would be at your door much faster with some to share!

Amazon product ASIN B08C7HJK9H
 
Since you issue involves a disconnection and not just noise in your music I'm not really sure but I'm guessing noisy power is the problem. If you have your phone plugged in (lighter/other 12v) try unplugging it and just use phone battery. Does that fix it? If not then you need to try powering the entire redirad system with an external 12v battery (drill, another car battery) or wall wart that puts out 12v. If that fixes it you need an isolated power supply. They are not that common. It will take a while from china. There are plenty of small isolated DC-DC 12v isolated power supplies but they usually are only outputting milliamps...not enough for your needs. If you search ground loops and power supplies especially related to digital signal processors, you will see some familiar issues. Why don't you call Redirad. Old cars have all kinds of noise, they probably have heard of it.

I bought the second one for my Bluetooth project but have not used it yet - avoiding 12v noise is the goal.

DC-DC Isolated Step-Down Power Suply Module 12V-90V to 9V 12V 19V 24V 4A 3A | eBay

https://www.aliexpress.us/item/3256...2i3EP1w&gatewayAdapt=glo2usa&_randl_shipto=US
Phone not plugged into car but it is the phone which disconnects and quits transmitting via blue tooth. Therefore, logic would be it is not a power supply issue from the "transmitter" At the same time, if it is a drop in the power to the Blue Tooth Receiver in the car which then of course has nothing to do with the phone, I would suspect that I would see a drop or flicker in the Volt Meter which I don't. Has to be interference which the phone is reacting and since it is the phone, it cannot be the Adapter or the Blue Tooth Receiver.
 
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