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let's solve the bluetooth problem


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In a recent post I asked for help designing bluetooth earbuds that still have the option to be plugged in through an aux cord. After taking polls and doing some research I've come to the conclusion that there are many people suffer from the same problem and I know we can come up with a way to add a 3.5mm input to bluetooth earbuds. I have created a circuit that can do this but you have to manually use a switch to change the path of the incoming signals so that they dont get sent into the receiving circuit itself, that would permanently destroy it. But that has to be done every time and it could easily be forgotten. Does anyone else have a better solution?


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Does anyone else have a better solution?
Self-discipline? Training yourself to use the toilet before leaving the house. Training yourself to pay your bills on time. Training yourself to charge your phone on a daily basis. Training yourself to charge your earbuds on a regular basis. For that matter, maybe train yourself to use your earbuds on a regular basis so you remember to pull them out of your backpack at the end of the day and charge them because they are important to you.

Ian Rogers

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Personally... If its a problem, just buy wired ear buds... I use the wired type with no issues at all... Assuming the Bluetooth device is dead ( requires recharge ) .. You would need to disconnect the internal amp and redirect to the jack... A lot of messing.. AND! for the price of these things!! Is it worth the hassle???


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Electrically it is extremely simple - most jack socket sizes are available with internal "break" contacts, eg. as used to disconnect internal speakers when headphones are connected.

Those break contacts could equally be used to disconnect the internal amp.

In practice, that needs significant extra space in the bluetooth receiver, for earbuds that are wired to a single receiver unit.

For wire-free earbuds it would make each unit far larger, likely to the point of complete impracticality.

There are simple off-the-shelf alternates to all that.

Carry a a pair of conventional wired ones and swap to them.
Or, use a wired pair all the time, normally plugged in to a separate bluetooth adapter (many types of which are readily available).
If the battery in that fails, just move the plug to the actual audio source.


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Training yourself to charge your earbuds on a regular basis.
this is one reason the OP might have a shot at a "million dollar idea". i've seen a trend from the pre-internet days of home computing until the present where there's an undercurrent of "i just want something that works with no effort." the reason not many people these days have any kind of online privacy or security is because "one extra mouse click is too hard". for internet security to work, it has to be completely transparent to the average user. it needs a very high "lazy quotient" to be successful.
i was kinda skeptical about the OP's idea, but it does hit on the "lazy quotient", and those kind of ideas do tend to sell. combining two features that are more often mutually exclusive? yeah, that could work.

use a bluetooth module that provides a line level (1V rms or so) output, and attach a 3.5mm connection parallel to the analog output of the bluetooth.... isolate the output of the bluetooth and the 3.5mm plug using 1k resistors


Just had a 10 million dollar idea - and I am willing to give it away for free....

Design buds where the rechargeable batteries can be easily swapped out, and provide an off-line charger that can charge at least two flat batteries at a time.

Just buy as many batteries as you need to get you through the day.

Some early mobile phones used to work this way. You could buy a second battery to swap out and charge it in a cradle. I miss that system :(


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Some early mobile phones used to work this way. You could buy a second battery to swap out and charge it in a cradle. I miss that system :(
Mitsubishi MT-5 with a spare standard battery, plus an extended battery for camping and/or fishing.


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The zinc-air button battery cells for my hearing aids last for 10 to 12 days and are inexpensive. New hearing aids have rechargeable battery cells that must be charged every night, a nuisance.

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