Hello, I'm looking for a DAA module to use with an arduino to connect to a telephone line. I've read a few guides that point to ebay sellers for DAA resellers. Does anyone know of a DAA module on mouser or some place with reasonable prices and preferably able to connect to a bread board?
Well if you want to try a real cheap hack, just look for an old Hayes modem at thrift stores or E-bay. Also old PC modem cards have DAA sections on them that you can hack into.
Thanks for the info richard! I'm trying to make an alarm system people can use with their sump pumps. We recently had our house flooded because the water detector alarm was inaudible from upstairs. I'm going to create a little device that will instead of alarming call a bunch of preprogrammed phone numbers and alert the owner of the house. This won't be a "huge" sales venture, probably just to people in my neighborhood. I'd probably want to stay on the safe side with a certified DAA. Do you know of any that I could plug into a bread board I could get from a legit supplier (read: non-ebay)?
Here's a telephone dialer and receiver project I did using a DAA. A source for a cheap Cermetek DAA module is included . . .
Thanks for the reply BroHogan. I've got the Cermetek DAA plugged in to my arduino, and hooked up to the phone line. It successfully takes the phone off the hook, but the DTMF codes coming out of it are barely audible, and the CO can't hear them. I've got pins 11 and 12 generating the tones using the Tone library, and when I plug them into speakers they are very audible, but not through the DAA.
I currently have the 5 volts, ground, hook line, the audio input, and the two wires running to the telephone jack plugged in. I don't have the audio output (coming from the DAA to the arduino) connected. Any advice?
I’ve already got the DTMF codes generating fine though. When I plug them into a Bose 301 speaker I can hear them loud and proud.
The two tones are generated on two separate wires (11 + 12) then merged and pushed into the DAA. Off hook line is 7, 5v is red ground is black.
Sorry I added the picture to the post before yours as you were posting yourself.
@mlapaglia As you can see from my project I used a 70¢ Holtek HT9200B DTMF generator chip (from Futurlec) instead of the tone() lib for DTMF.
However, I'm still a bit surprised your not getting enough output from tone(). I think it way cool that the tone lib can generate DTMF and it should be accurate enough. So you might be loading the output.
Try this - add a .1uf cap in series with the tone() output and pin 8 of the DAA. See http://dl.dropbox.com/u/3572198/Nex10%20Dialer%201.5.png
Oh wow, I just re-read the Cermetek spec sheet, I'm supposed to have a cap in the line before it reaches the DAA. Sorry I'll post back once I've got it fixed.
EDIT: Thanks Richard, I'll also do that.
Looks like I need to type faster!
Yep, added the capacitor now it's nice and loud. Thanks everyone for the support :)