Good day.
I am quadriplegic and I am connected to a ventilator. the alarm is active
for two seconds and off for two seconds, successively until it is deactivated.
I found your “MK139.”
My question is would it be possible to use “MK139” to detect other sound than
hand claps. I can’t use my hands but if it could detect for example tongue claps,
whistling or whistle.
My idea would be to connect “MK139” to a switch that activates a wireless buzzer
in order to increase the distance of the alarm.
I appreciate your attention.
Yours sincerely,
Inacio Moreira
Hello again.
I was thinking, if I used a more sensitive microphone exchanging the original one.
Or even use these (LM386 Low Voltage Audio Power Amplifier) or (Analog Sound Sensor (SKU: DFR0034)) or (Microfone Electret BOB-09964 )) in the place of the microphone, would it work increasing the sound gain?
Then I think the MK139 will be capable of detecting whistles or other sounds made with the mouth.
Do you think it could work?
I appreciate your attention.
Yours sincerely,
Inacio Moreira
The mk139 is assembled and in operation.
But only 50% of the claps (more or less) activate the relay.
The whistles and tongue claps, dont activate the relay.
What can I do to improve the operation of the relay, as the microphone works well, the LED flashes when detects sound.
The only change I made was to use LEDs in mk139 4mm, but I think it does not interfere in the functioning.
Please note that the clap sequence must be 100% correct:
Period of silence - clap - silence - clap - period of silence -> relay activates.
Make sure ‘clap’ is not too long or too short.
Any deviation will restart the unit and the relay will not activate (to avoid undesired turn-on)
The gain is already quite high. If you increase it further, the unit will be more susceptible to noise and interference which will affect performance.
Bringing the microphone closer to the source of sound is a better solution.
Please experiment.
Also: Make sure the power supply for the MK139 devlivers a clean 12V DC.