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blutooth telephone Answered

Hi people who are smarter than me! I have been searching the great Google for the past while and I cannot find something that does this.
I love the portability of cellphones and i love the look an feel of landlines (you cannot beat the look of a phone on a a desk. What I want is a device that connects to my cellular telephone wirelessly and that a landline can plug into. This means that it must supply about 40 - 60 VDC to power an old phone that DOES NOT HAVE EXTERNAL POWER SUPPLY so it could operate a touch tone phone from the 80's and 90's. When I get a call on my phone I want it to ring the phone. When I pick up the handset I want it to answer the call and allow me to talk to the person. When I place a call I want to be able to pick up the handset and then dial a 10 digit number and then it place the call through my cell phone. During the call I want to be able to press a number on the landline and for it to press that number on my phones keypad. when i put the handset down i want it to hang up. Is this even possible? can it be done? let me know!



1 year ago

AFAIK these old phones already work fine with 9V DC - at least the ones with the round, interrupter style dial.
I think what could work almost for your purpose is a normal BT hands free kit as a salvage object.
This can pair to your phone and you can replace the phones speaker and mic with the ones from the BT kit.
And a button from the phone can be rewired to answer a call - or simply use the one for the handset as per original design.
If you do need the original ringer to work it is a bit more difficult though...
Most proper BT kits, apart from a button to answer a call, also have some sort of visible indicators for incoming calls - usually a LED.
You can utilise the signal for this particular LED as an input for a little circuit that activates the original ringer.
Or course the how to depends on the type of ringer and standard ringtone for the phone in question.
You could also use a little audio module to play an oldschool ring through a speaker - this way all can be powered from a standard USB adapter or a 12V power supply.


1 year ago

Hey Scott!

I am currently working on the same kind of project. I bought this bluetooth adapter from ebay (from China) for 2.50€.

I then replaced the old phone mic with it to use the mic from the adaptor and hooked the phones "speaker" to the line. Since the phone has 4 wires from the base to the "handle" (sorry, I am from Germany and don't know exactly how you name all the things) I used 2 of them, soldered a micro USB connector to it and use it as power supply. Inside the base I removed the old electronics and added a USB port to provide 5v from an external source.

This works fine so far, BUT: the phone is not ringing, the dial is not used and it doesn't pick up a call when you pick it up.

So I just ordered two additional bluetooth modules (CSR-A64215) to play with them from ali express (also china, so it will take another 4 weeks for them to arrive)

How about to team up and share our findings? I am quite good with atmel controllers and arduino, but bluetooth is new to me and I am still not sure how exactly the whole thing will work. My open questions are:

- which bluetooth-profiles need to be supported

- how does a cellphone informs a bluetooth module about an incoming call

- how does a bluetooth module pick up a call

- how does a bluetooth module dial a number and start a call

Kind regards,



Reply 1 year ago

Oh, and maybe it is worth saying that I want my old landline phone "just as a repeater" for my regular mobile. I don't want to add an gsm module and an additional sim... Like a monster headset with dial buttons :-)


1 year ago


Just so you know I am clueless about how you would do what you have said directly - however if you removed the combined landline functionality for one second I feel there is definitely suggestions as to how you could start to think about this from a purely - cellphone & pretty looking receiver perspective:

Just as a suggestion a quick solution could be to buy an iPhone retro handset like this - https://www.amazon.com/gp/product/B001O7VZMK/ and pair the handset with a similar looking base unit. This way you could empty the contents of obsolete base unit and have it as a shell - thread 3.5mm cable from the handset peice to the base unit (perhaps even empty the contents of the sprial cord and thread it through it) and use the base unit as a housing for some sort of bluetooth receiver for your iPhone. This would be receiver only

My ideas would be more code-oriented in terms of using the landline unit to dial out after that - if you had an Arduino or something similar you could look into software that sends requests to your iPhone through interfacing programs. I have been looking at ways to try and do the exact same thing for a different purpose, but it is difficult to find a way that would transit data from Arduino input to iPhone - I have been looking at Jubito which looks like it might be able to but I don't understand it. Here's the link regardless: http://jubito.org/


Reply 1 year ago

Thanks. I like that idea. The 3.5mm jack could be replaced with a phone cord.the coding and Arduino is above my head but that is an excellent idea. Thanks.


Reply 1 year ago

No worries - also my original suggestion used an Arduino with a bluetooth receiver so that you could communicate with the phone - this would be the most ideal as it could be programmed specifically for your purpose - but Arduino programming is something I know little about also -

Instead you could hack this: https://www.amazon.co.uk/Bluetooth-Transmitter-TaoTronics-Portable-Wireless/dp/B00Q2EGQQU/ref=pd_sbs_23_1?_encoding=UTF8&psc=1&refRID=F8CV0Q5F4WDWKGEQRPJM

Or a version similar: put a female- female adapter on the end to receive the lead from the handset and solder a constant power source to it's circuit (so that it stays on, would not be receiving power otherwise) and that would be your bluetooth transmitter. They might even make battery versions tbh, just depends what you want to do