Hello everyone, I have a Spark Core, I’m a bit new to hardware, and I’m trying to hack the wall control box of my climate unit. I read a lot of topics about this, here or on other sites, but I think that I’m missing something so I ask for help.
Opening the box and looking at the manual I found an 8-pin plug, where the #1 is the 12v that powers the board. What I’m trying to do at the moment should be pretty simple: I just want to unplug the 12v cable from the pin, put my spark core serially between the 12v cable and the #1 pin and use it as a remote switch. Using a multimeter, I found that the current between the 12v cable and the pin is 40mA.
As far as I understood, I think that I could achieve this using a transistor, so i’m trying to use the SS9013 (the one bundled with the Spark Core maker kit), with a lot of combinations with resistors and so on. I know that I have to connect a Core digital pin to the base (I used a 1k ohm resistor before the base), the collector to the external 12v cable and the emitter to the input pin, but I really can’t find a way to make it work.
Can you give me an advice, maybe a circuit scheme, and most of all, a step-by-step explanation of whats going on? I’m new to this and I think I’m missing something with voltage or amperage.