Simple inertia dyno Arduino shield, need more eyes on my pcb/circuit.

[adegnes]

Hi, I'm new here! (and fairly new to electronics)

Here's a arduino shield for a motorcycle inertia dynamometer I've built.
 I've got the dyno up and running with just the roller pickup wired into the arduino with a pull up, but I also need engine rpm.

I'm using this software: (works great BTW, and is free) https://sites.google.com/site/simpledyno/home

My rpm pickup circuit is based on/copied from this site:
http://www.sportdevices.co.uk/rpm_readings/index.htm

The connector labeled with the lightning is from the spark plug wire pickup, wich is just a coax cable coiled two turns around the plug wire. "-" is connected to the coax shielding. The signal is entering the board on the top layer and is transmitted to the bottom layer by capacitive coupling before it enters the 100p cap.
 
The connector labeled with the "wheel" is the roller pickup, a Honeywell 1gt101dc.


It would be great if someone could comment on my pcb layout and the circuit;
Anything obviously wrong?
What could be done better?
Right choice of component values?

Thanks!

[pmbrunelle]

What is the Arduino for?

Do the sensor inputs go to the Arduino, and then the data is sent to the computer program by UART?

Because the SimpleDyno website shows that the data acquisition is by the computer sound card... but I don't think you want to blast the sound card input with a 5V square wave from the 555.

[adegnes]

What is the Arduino for?

Do the sensor inputs go to the Arduino, and then the data is sent to the computer program by UART?

Because the SimpleDyno website shows that the data acquisition is by the computer sound card... but I don't think you want to blast the sound card input with a 5V square wave from the 555.

You've just overlooked it...
from their front page:
"SimpleDyno 6.3 expands your data acquisition options by introducing support for microcontrollers such as the Arduino UNO."

Digital pin 2 is rpm1 - dyno roler, pin3 is rpm2 - engine rpm.
Analog pin 0-6 is used for logging analog signals from temp sensors etc.

[rickey1990]

Hope this helps https://www.reddit.com/r/arduino/comments/2o4vxp/reading_engine_ignition_pulses/ and nice looking board

[adegnes]

Thanks!

[alexanderbrevig]

Looks good to me Good job!
Velkommen

[adegnes]

Takk takk!