Ok folks heres the deal...

I have a PC Gamer's Headset i use for listening to music and gaming on my pc. I wish to build a small device that connects to the phone line and has connections for the headsets headphone and mic plugs and a hook on/off switch so that i can use it to answer incomming calls if it wish. The headset already has its own volume control for the headphone but a gain control for the mic would be handy too. Diagram below to give u an idea of what i mean.



I have also posted this at another electronics forum site too!

__________________
Dave Pusey.
PIC Programming Tutorials: http://www.mstracey.btinternet.co.uk...al/picmain.htm
Brilliant PIC Simulator: http://www.oshonsoft.com/pic.html

 

Hi Dave,

As you are in the UK I should mention that this is seriously frowned upon, any device connected to the UK telephone network has to pass strict approval tests - penalties can be severe, as I understand it fines can be unlimited!.

You can buy devices to do what you require, most call centres use something similar - far safer to do that.

__________________
PIC programmer software, and PIC Tutorials at:
http://www.winpicprog.co.uk

 

err, the easiest thing is probably to find a phone where the handset connects to the main bit of the phone through a socket, on the side or back of the phone usually. Connect the headset to this socket.

Two things to consider. One is that the mic on ur headset is probably the electret type, and requires power. The second is that the headphones are stereo, whereas the phone is mono.

Tim

 

I seriously doubt that a headset adaptor is gonna cause a problem. I would prefer to build my own because it works out cheaper and a hell of a lot more fun.

Never been able to find any phones like that. Perhaps ebay?

Well it plugs directly into soundcard so probably not.

That doesnt matter. I'll just connect left and right together to send signal to both ears.

__________________
Dave Pusey.
PIC Programming Tutorials: http://www.mstracey.btinternet.co.uk...al/picmain.htm
Brilliant PIC Simulator: http://www.oshonsoft.com/pic.html

 

If i cant find a phone with an unplugable handset perhaps i could get a permentantly corded one and connect a 3.5mm jack socket in place of the speaker, and another socket in place of the mic. Then replace the hook switch assembly with a simple toggle switch.

Would that do it?

__________________
Dave Pusey.
PIC Programming Tutorials: http://www.mstracey.btinternet.co.uk...al/picmain.htm
Brilliant PIC Simulator: http://www.oshonsoft.com/pic.html

 

computer mics that plug directly into your soundcard have three connections (look at the plug on it), one is ground, one is signal, one is power.

I imagin that the hook is simply a push switch, so a toggle would probably work.

errr, sort of. The connections on the cord between the phone and the handset should be ground and signal for the speaker, ground and signal for the mic (you may want to check that first - look in google). You may have to take the handset apart to find out which wires are which.

The only reason i suggested a phone with an un-pluggable handset was because you could switch between your headset, and the handset at will, but this doesn't matter too much if your not bothered about the phone.

I would check very carefully first (Nigel knows what he's talking about...)

Hope it helps.

Tim

 

How do i find out which connection is which? (tip,ring,body)
There is a pinout here (scroll down to Microphones). Is that image (see below) correct?


I'm gonna have to do that because i dont have any spare phones with unplugable handsets.

Dont care about rest of the phone. When it rings i just put on headset and flick the hook switch to the "Connect" position. When call is complete, flick it back to "Disconnect" position. If i need to use a handset (which i probably wont) i will just pick up my cordless.

The purpose of all this is so that i've got both my hands free for operating my pc whilst conversing on the phone as i often have to look up stuff on google when helping person on phone with a pc problem.[/img]

__________________
Dave Pusey.
PIC Programming Tutorials: http://www.mstracey.btinternet.co.uk...al/picmain.htm
Brilliant PIC Simulator: http://www.oshonsoft.com/pic.html

 

yep, thats right.

that atitude is always helpful when building stuff!!

try building it all, see what happens, but check out the rules first, fines are not nice.

Any other questions, just ask.

Tim

 

Ok. I've just had a word with my dad and he has an old one-piece (every thing the handset - see here) phone that i can butcher. I'm gonna replace the speaker and mic with sockets and the hook assembly with a toggle switch as discussed earlier. I'm mount all the phone's boards into a project box to cheap it nice and neat. The problem i now have is can i use something like a 78L05 to power the electrec mic from the phone line. If i can, how?

__________________
Dave Pusey.
PIC Programming Tutorials: http://www.mstracey.btinternet.co.uk...al/picmain.htm
Brilliant PIC Simulator: http://www.oshonsoft.com/pic.html

 

How about a speaker phone?? you could connect your earphones to it if you want privacy...

__________________
gerty

 

The headphones (if you look at the diagram at the top of this topic) is always connected. There will be no speakers.

__________________
Dave Pusey.
PIC Programming Tutorials: http://www.mstracey.btinternet.co.uk...al/picmain.htm
Brilliant PIC Simulator: http://www.oshonsoft.com/pic.html

 

Here is a scan of the mic currently in the phone. As you can see it has two wires. How to i convert this for connection to my electrec mic headset as we discussed earlier. Also, can i use a 78L05 to power the electrec mic from the phone line. If i can do this, how do i do this?

Attached Images

phone3.jpg (9.6 KB, 279 views)

__________________
Dave Pusey.
PIC Programming Tutorials: http://www.mstracey.btinternet.co.uk...al/picmain.htm
Brilliant PIC Simulator: http://www.oshonsoft.com/pic.html

 

hmm, the two wires connected to the mic in the picture will be ground and signal. err, not sure how you find out which is which - maybe someone else knows?. (see if you can look at the circuit board, and work out which wire is connected to ground).

as for power, i'm not sure what power the mic will need. It will probably be +5v, although I suspect that it will be fairly tolerant of a range of values. Again, i'm not really sure on that one. (if you want to check the voltage on the power connection on your computer, put a 3.5mm plug into the mic socket, and measure the voltage on the power connection)

am I right in thinking that a 78L05 gives 5v from a 9v input? I can't remeber - a 78L05 type IC will be perfect, but the question is where to get the power from? Maybe you can get some power from the phone? For the third time, I don't really know the answer!!

Sorry for being completly un-helpful, maybe someone else can help out here.

Tim

 

The 78L05 gives 5V ±4% at a max of 100mA from an input of 7V to 30V. I was hoping to connect the 78L05 somehow to phone line to get the 5V the mic needs.

__________________
Dave Pusey.
PIC Programming Tutorials: http://www.mstracey.btinternet.co.uk...al/picmain.htm
Brilliant PIC Simulator: http://www.oshonsoft.com/pic.html

 

hmm, not usre where you would get the 7v to 30v from, my only suggestion is a battery. In the mean time, take a look at this site. its a wealth of information on phones

http://web.ukonline.co.uk/freshwater/

Tim