7
loosen the knurled screw (left) counterclockwise, [3] tighten the knurled screw (right) clockwise as far as you can, and
then [4] tighten the screw knob to lock the barrel again.
Launch the projectile again to check if the projectile hits the string. If not, repeat above procedure.
6.
Only after making sure the projectile constantly hits the string, move to the next step to adjust the launching angle in the
vertical direction.
2-1. How to adjust the launching angle in vertical direction:
1. Remove MRP from BRU.
2. Set the output voltages of the power supply to DC 3V.
3.
Grasp the knob of SFP and slowly take SFP from the barrel. This automatically alters the built-in micro switch from the
off state to on state, which starts the power supply to the coil of BRU. The iron core of BRU becomes magnetized.
4. Latch SFP at one of its four equally spaced shallow cuts (grooves) and stick the “Free-falling Object” to the iron core of
BRU.
5. Lower the voltage of the power supplied to BRU and detect a threshold voltage value at which BRU can no longer
suspend the plastic ball electromagnetically (the threshold should be somewhere between1.2V and 2.5V).
6. Repeat above step 1 to 5 until determining the threshold out-put voltage. Once determining it, do not change the setting
of the power supply.
7. Check if launched projectile hits the free-falling object. If not, observe whether the projectile trajectory travels over the
free-falling object or beneath it.
8. If beneath, slightly lower the out-put voltage, so that BRU would bear less remanent magnetization* and the free-falling
object would be released more synchronously.
9. Launch the projectile again. If the projectile rarely hits the free-falling object, nevertheless, move to the next step below.
* Remanent magnetization of BRU may defer the releasing timing of the free-falling object.
2-2. How to adjust the launching angle in vertical direction:
Consider the following procedure as the last resort for a successful demonstration. If this procedure does not work, do not
adjust the product further and contact the distributor.
a) To adjust the launching angle upward: Slowly rotate a screw with a built-in knob (1) counterclockwise little by
little to increase the elevation angle of the barrel against the lower boom.
