MK120 use to trigger a MP3 player

Kits Mini Kits Range
1

Is it possible to use this kit to trigger a mp3 player (such as the sparkfun mp3)

My idea was to leave the buzzer out of the circuit and to use it as a trigger to play MP3’s. I would like to connect the + and - (where the buzzer should normally be) to the + and - trigger input of the mp3 player but I do not know the output VA of the + and -.

These kits would be useful in our museum ie if someone passes the MK120 than een audiofile on the MP3 player would start to play. Can I change the frequency so multible MK120 could be used (the sparkfun MP3 can be triggered 18 times via different “IR eyes” or something like that. I would make it myself to cut costs (as we are a starting young museum without loads of cash)

Good or bad idea? Any other sugestions are obvious more than welcome.

Thanx

Steve

2

Most likely, the MP3 player needs a contact that closes as a trigger.
You can replace the buzzer with a small relay. Make sure to put an 1N4148 diode over the relay coil.
No need to change the frequency of the MK120, as the IR beam is extremely narrow.

3

I’ve got this wired up via a 12v relay too to trigger a talking pumpkin for halloween … what is the purpose of the diode? Does it matter which diode? Will a 1N4007 work also?

4

Yes, an 1N4007 will do too.
It protects the transistor.