/diy/ - Do It Yourself

bluetooth can connect to any number of projects, but as the other anon said, you will need an actual microcontroller.

If you develop any sort of proficiency with Android Studio, the visibility you get by connecting any android tablet or phone is awesome when it is warranted. Pic related is the starter voltage and current in my old truck, which would be very hard to obtain by any other method I'm familiar with. This is an old android phone and a nano, along with some sensors I made.

And now let me digress. The monkees who write Android Studio sit there at million dollar workstations with terabytes of ram and disk and think we all do. Until recently, fucking Gradle would save literally dozens of gigabytes of worthless shit on your computer for no reason. I'm not sure they fixed that; I reverted to an obsolete version of Android Studio that can no longer put apps on the play store, but doesn't rape my system every time I load a project.

>>1970375
>It's a 1985 Ford with a straight 6 engine, the cranking amps it needs are about equal to a motorcycle.
Pic related is my 84 Ford F150 with 300 I6. You must have one hell of a motorcycle if it pulls close to 500 amps to start rotating.

>>1962149
>But here's a thought: Skilled mechanics can crank an engine and hear a low compression cylinder by the uneven cranking speed.

When this test is done properly with a scope and you also show pulse from a cylinder, this test tells you which cylinder has low compression. I'm guessing your skilled mechanic is not so good at that.

>>1962193
Correct. People tend to assume everyone has a newish car. Pic related is my 84 ford F150 300 I6 which surges to about 500 amps to get the engine rotating, then is about 170 amps for the peaks later on. When I did this test I had never heard of the relative compression test, but it looks like mine are ok. (Ignore the voltage scale which is the arduino ADC 0-5 volts). This is a home made current probe using an analog hall sensor, arduino nano with bluetooth to send the trace to my phone.

>>1848225

yes. I used a core made from motor laminations to sense the starter current in my truck. You can adjust the air gap to handle pretty much any current.

Got bored so I programmed a nano to monitor the voltage and current at my truck's starter motor. Sensor is linear hall AH3503. I used a few lams from an old starter motor to concentrate the flux. In pic related the voltage scale is misleading because I wanted to see the actual 0-5v from the hall; the green plot is the voltage at the starter and is about 9 volts maximum for most of the plot.