Here we have a stand alone DTMF Tone Generator. If you do not know what DTMF Tones are, they are the tones that Telephone keypads made back in the day on your landline telephone keypad. This is a stand alone compact single board with a built in speaker and amplifier chip, DTMF chip to generate the tones, and it's own power supply. Simply connect a 12v DC power supply to the + and - terminals on the terminal block and short a wire between the COM and any of the A B C or D terminals to make different audible DTMF tones. Things like this were used a lot in 80's television shows like Airwolf, Knight Rider, and even Back to the Future! These boards can be used to make button panels have a DTMF tone when a button is pressed! This is what they are mainly used for and what I have used them for. I have used these boards to make Stream decks, CAD hot key panels and even a security system! Very useful and versatile! They also use actual DTMF Chips to get screen accurate sound possible, No microcontrollers used here!
There is also a few options on the board already that can be changed by the end user! The pin block by the speaker can be changed around to create different tones as well by moving the supplied jumper to the other selections in the same orientation of course. So one could have 4 of these boards in a project to make up to 16 different tones! There is also an adjustment Potentiometer to adjust the gain of the speaker! The mounting holes are made for M3 screws/standoffs to make it easier to mount inside you project and even stack several of them together. Most Electronics hobbyists already have M3 stand offs laying around in a parts bin! The board measures 6.2mm x 8.2mm
A small tip to make the tones even louder is to set the board back in your project a bit and use something like a Toilet Paper tube or a piece of buying pipe to bring the sound to the front panel. In doing so, this will bring the sound up another 5 - 10 dB.
When ordering this board from me, there are a few options I can give you with it. I can make the COM pin either be a Positive trigger or a Ground trigger. This means that one could use a ground or a positive 12vdc wire to trigger the ABC and D terminals. When ordering, please let me know of what you plan to do with it so I can better set this up for you. I can also ship it without the terminal blocks soldered and give you the option of having a custom connector instead. There is an option of using a 7 pin (2.54mm spacing between pins) Header, Molex KK series, or a JST XH series 7 pin connector. Furthermore I can also ship the board with the speaker not soldered in and have it on a wire harness for you with the use of the other two pin connector used! Please let me know before ordering what you would like. Please do not hesitate to contact me about anything or any questions you may have about this product or any other product.
Disclaimer: If you do not give me any information and just order the board, you will get the board with the terminals soldered and the speaker soldered in place and with a Ground Trigger at the COM terminal! Furthermore, If you have a Ground Trigger board and try to use Positive 12v to trigger the ABC and D terminals, you will destroy the DTMF chip, so please keep in mind of what board you have ordered from me. Keep in mind this is a circuit board with electronic components soldered to it. Care should be taken with ESD and exposure to open electronics components. Furthermore, Revision numbers, components used, board colour, and layout it subject to change without notice. This does not affect the functionality of the device listed!
There are no refunds on this because they are made to order and when you pay, that money goes in to making your product!
Product code: DTMF Tone Generator buying