13.Mar.2003
Carsten Siegner (ANF)
|
Compass Hardware for Amiga (Principle Circuit)
Carsten Siegner has built a principle circuit for a compass. This circuit is unusually sensitive and already detect the north pole
of the Earth's magnetic field.
For the operation here comes a very sensitive KMZ-51 magnetic field sensor. This includes a sensitivity of - 0.2
kA/m to + 0.2kA/m. Built into the chip are magnetic recessive resistances in the form of a Wheatstone bridge. The sensitivity
(uncompensated), relative to measurement setting, carries (16mV/V) /
(kA/m).
Attention: the sensor is circuit broken in an SMD housing and on that account may only be soldered with great
difficulty. The sensor can pick up the electrical field of the computer. So one must compensate for this. One may not
divert a magnetic field greater than 1 kA/m with the sensor, or else the Wheatstone bridge will always keep the exit value.
In order for this not to happen one must use the chip's internal reset coils. The chip ZN424 is unfortunately very difficult to
flush. Unfortunately it is so far the only operation enhancer that can energize the tension variables of the Earth-field
detector. Siegner tested other OPs, but none came close to the strengthening of the ZN424.
Unfortunately the software programming is not as simple a thing as the hardware. The measurement
value fluctuates constantly due to the diverting magnetic fields of the TV or the computer. On account of that one can't
directly recognize the Earth's magnetic field. Of course when one adjusts the circuit slowly then one recognizes that the
measurement value declines further, the more the sensor is turned from the north-south position. Because the sensor
is now polarized, this means that one can differentiate a magnetic field between north and south, and may now recognize
the Earth's magnetic field from the correction measurement value. Only the calculations of the whole thing are going to be
beautifully difficult. Every metallic resistance will cause disturbance to the setting of the measurement values. (nba) (Translation: dm)
[News message: 13. Mar. 2003, 23:43] [Comments: 0]
[Send via e-mail] [Print version] [ASCII version]
|
