Anyone have details on how the Avocet 30 cyclocomputer magnet ring works?

[Dr Dremel]

Proper nerdy in here, never knew I would find cycling computers interesting.

Going from what @novocaine posted, maybe if you half the number of magnets in the 3D printed ring it would help the sensor pick up the changes in the magnetic field more easily? If it´s possible to double the wheel circumference via calibration it should even read the correct speed?

 

[novocaine]

Proper nerdy in here, never knew I would find cycling computers interesting.

Going from what @novocaine posted, maybe if you half the number of magnets in the 3D printed ring it would help the sensor pick up the changes in the magnetic field more easily? If it´s possible to double the wheel circumference via calibration it should even read the correct speed?

I'm not sure that would help as you are still within the interacting fields due to the distance from the sensor head. a weaker magnet would be a better option to flatten the interacting fields.

this is getting silly

 

[Dr Dremel]

this is getting silly

and I love it

 

[dirttorpedo]

So is the goal here to have a functioning head unit or to have the entire unit function as per original design? If the former, can you swap out the magnetic ring for a more traditional avocet sensor and spoke mangnet system?

 

[novocaine]

So is the goal here to have a functioning head unit or to have the entire unit function as per original design? If the former, can you swap out the magnetic ring for a more traditional avocet sensor and spoke mangnet system?

that would entirely depend on what the unit is expecting to see, but I suspect not as there is no voltage output to the sensor (it's passive, a small current is generated by induction as the magnet passes the coil). A more typical reed switch requires a circuit to break.

I think an oscilloscope would be a useful tool here to see what the coil is generating in terms of a wave form. I think a much deeper dive into a head unit to see how it works would also be doable.