Took a look inside the control unit of a crosstrainer. Was on the search for some longer cables and switches. Kind of a dumbster dive.
Front of the unit. Nothing interesting going on. Big LC-Display (or LCD for short), knobs, buttons and a USB port.
However the internals are quite interesting:
A few things to note:
Plugs everywhere! The whole thing basically is plugged together! No idea why anyone would do that, no consumer would ever take a look in here or service anything. Note that all components are through-hole making them easier to solder by hand.
And all the chips are name brand, all TI (texas instruments) or IR (international rectifier).
Now it turns from interesting to confusing:
The black blob covers a microcontroller on the PCB making it cheap and easy to connect to the board. However someone seems to have been desperate and put it in a socket of sorts. So there are 4 bars of pins serving as a “cpu socket”.
Remember the USB connector? It is physically a USB connector, electrically, it is not.
Took a look into the “USB”-dongles…
The top one is a real USB stick. The two below that are NOT! The 4 lines in there end in solder pads. In the one I turned over, GND and +5V (the two outer pins in USB2.0 connectores) are connected together. Plugging that into any computer will probably render that USB port unuseable.
Here is a close up shot. I marked the two rails. The lower most soldering pad is barely connected (checked by probing it). Would probably allow for 3 A or more to flow.
I got about 3m of “rainbow cable” wich I will put connectors on and use in some project:
2x 3.5mm "mono audio jacks"
And a bunch of wires plus some things from the controller.