I'm going to use this thread to explain, to the best of my knowledge, why the HES bounce issue occurs and how it is eliminated by changing the magnetic polarity of the coil (solenoid).
The solenoid is a coil. It has a winding around an iron core. The coil acts as a magnet when energized and creates a magnetic field, which is actually the flux lines traveling from north to south. Of course you can't see this flux, but physically it is emitted from the solenoid and because of the closeness in proximity of the solenoid and the HES, that flux can interfere with the magnetic field produced by the HES. Basically, due to the hysterisis of the HES chip, there is a very small point at which the HES chip is "activated" and when it is not. This is why you have to pull the trigger very slowly and hold it at that defined point to get the HES to bounce. What you're doing is you're holding the magnet at the point at which the HES is telling the gun to fire and then the flux from the solenoid is then interfering and telling the HES to fire again. Since the solenoid pulses for 20ms and at the interval at which you have your MROF set at, it's like a bunch of REALLY fast trigger pulls perfectly spaced apart.
You can check the magnetic polarity of a solenoid by setting a compass next to it. The needle will indicate your north and south poles while the solenoid is not energized. I took a few solenoids and laid them by a compass and the compass would clearly define the magnetic poles. However, when I sat a brand new solenoid next to it, the compass needle barely twitched. I thought about it for a minute and realized that since the coil acts like a magnet, it can have residual magnetisim. Since that new solenoid has not been energized other than maybe going through a test procedure when it was built, it does not have any residual magnetism, thus the compass was not reacting. I put a 9V battery to the two leads to energize the coil and put it next to the compass and it still wouldn't react. Thinking about it for a second and then realizing that I basically didn't put any current through the coil, so it didn't produce any flux, I grabbed a solenoid plunger, held it a ways out of the solenoid and then energized it. The plunger snapped into the solenoid and then I sat it next to the compass and sure enough the compass needle shifted itself quickly to show the magnetic polarity of the solenoid.
Through testing I found that the proper configuration of the solenoid is where, when energized, the south pole of the solenoid is at the TOP of the solenoid. This means the side that the plunger goes in. You can take any solenoid, put the plunger in it and put the two wires on a 9V battery. When you have current flowing through the solenoid and the south pole is facing up, you want to mark the wire that is on the positive lead of the battery and that's the wire you want to wire to the positive lead off of the board.
The polarity of the HES magnet is such that the north pole faces towards the HES chip. I'm assuming that when you pull the trigger and the gun fires, that switches and you have the magnetic field from the HES and from the solenoid repelling each other. Switch the wire leads on the solenoid and you have a flux coming out of the solenoid that moves right through the HES and interferes with the firing process.
That's how I see things. Feel free to comment/question anything I've just said.
The solenoid is a coil. It has a winding around an iron core. The coil acts as a magnet when energized and creates a magnetic field, which is actually the flux lines traveling from north to south. Of course you can't see this flux, but physically it is emitted from the solenoid and because of the closeness in proximity of the solenoid and the HES, that flux can interfere with the magnetic field produced by the HES. Basically, due to the hysterisis of the HES chip, there is a very small point at which the HES chip is "activated" and when it is not. This is why you have to pull the trigger very slowly and hold it at that defined point to get the HES to bounce. What you're doing is you're holding the magnet at the point at which the HES is telling the gun to fire and then the flux from the solenoid is then interfering and telling the HES to fire again. Since the solenoid pulses for 20ms and at the interval at which you have your MROF set at, it's like a bunch of REALLY fast trigger pulls perfectly spaced apart.
You can check the magnetic polarity of a solenoid by setting a compass next to it. The needle will indicate your north and south poles while the solenoid is not energized. I took a few solenoids and laid them by a compass and the compass would clearly define the magnetic poles. However, when I sat a brand new solenoid next to it, the compass needle barely twitched. I thought about it for a minute and realized that since the coil acts like a magnet, it can have residual magnetisim. Since that new solenoid has not been energized other than maybe going through a test procedure when it was built, it does not have any residual magnetism, thus the compass was not reacting. I put a 9V battery to the two leads to energize the coil and put it next to the compass and it still wouldn't react. Thinking about it for a second and then realizing that I basically didn't put any current through the coil, so it didn't produce any flux, I grabbed a solenoid plunger, held it a ways out of the solenoid and then energized it. The plunger snapped into the solenoid and then I sat it next to the compass and sure enough the compass needle shifted itself quickly to show the magnetic polarity of the solenoid.
Through testing I found that the proper configuration of the solenoid is where, when energized, the south pole of the solenoid is at the TOP of the solenoid. This means the side that the plunger goes in. You can take any solenoid, put the plunger in it and put the two wires on a 9V battery. When you have current flowing through the solenoid and the south pole is facing up, you want to mark the wire that is on the positive lead of the battery and that's the wire you want to wire to the positive lead off of the board.
The polarity of the HES magnet is such that the north pole faces towards the HES chip. I'm assuming that when you pull the trigger and the gun fires, that switches and you have the magnetic field from the HES and from the solenoid repelling each other. Switch the wire leads on the solenoid and you have a flux coming out of the solenoid that moves right through the HES and interferes with the firing process.
That's how I see things. Feel free to comment/question anything I've just said.
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