A cyclotron is a type of particle accelerator which repeatedly propels a beam of charged particles (protons) in a circular path. Cyclotron uses electromagnetic fields to propel charged particles to very high speeds and energies and is used to produce radioisotopes for a type of medical drugs called radiopharmaceuticals, which diagnose and treat cancer. There are over 1500 cyclotron facilities around the world according to IAEA.
So a cyclotron repeatedly propels particles in a helical path, (not along a circular guide like the plastic tube in your setup, if you constructed it like in the linked Youtube video) achieved by two opposing electromagnets and varying electrostatic field. Charged particles are accelerated outwards from the centre of a flat cylindrical vacuum chamber along a spiral path until they finally land in the bombardment chamber. So in a cyclotron particles are held to a spiral trajectory by a static magnetic field (two electromagnets) and accelerated by a rapidly varying electric field.
In your setup, two electromagnets are used as accelerators, not as guides for the pellet. So pellet is actually guided by the plastic tube along the circular path. A cyclotron, by contrast, uses a magnetic field to bend the trajectories of particles into spiral paths. So basically the setup in the youtube video accelerates the pellets in a two-dimensional path (if you disregard slight deviations due to non-uniform force and gravity) along a circular plastic guide until the setup is turned off manually while the cyclotron accelerates beams of particles in a 3-dimensional vacuum along a helical path until the particle eventually reach and collide in the bombardment chamber.
In the above diagram from Wikipedia the electromagnet pole pieces are not shown full size; they must be at least as big as the dees in order to create a uniform field"
As you can see in the diagram above there are no tube-like structures but rather two D-shaped metal hollows with a gap in the middle. The whole device is enclosed in a vacuum chamber. Particles, first released into the middle of the Dees are accelerated through this gap repeatedly. Here is a modified excerpt from Wikipedia that better describes the procedure.
"It (the cyclotron)consists of a pair of "D" shaped sheet metal
electrodes called "Dees" placed face to face inside a vacuum chamber,
between the poles of an electromagnet. An oscillating radio frequency
voltage of several thousand volts is applied to the dees. Atomic
particles to be accelerated, such as protons are released in the
center. The magnetic field causes them to travel in a spiral path from
the centre to the rim of the dees, being accelerated each time they
pass from one electrode to the other. When the particles reach the rim
they pass out of the dees through a small gap and strike a target."
The device in the linked youtube video is actually an incorrect model of actual cyclotrons. Such a cyclotron model will be highly inefficient for actual particle acceleration as most of the particles' energy will be dissipated by the collision with the wall of the plastic tube.
Inspired by a paper from Norwegian engineer Rolf Wideroe, Ernest Lawrence (1901 – 1958) invented a unique circular particle accelerator, (which he referred to as his "proton merry-go-round" but became better known as "cyclotron") with a pie-shaped concoction of glass, sealing wax, and bronze. A kitchen chair and a wire-coiled clothes tree were also used to make the device work. Ernest Lawrence won the Nobel Prize in 1939 for the invention of the cyclotron. Cyclotrons were the most powerful particle accelerator technology until the 1950s when the synchrotrons superseded them but are still widely used in the field of nuclear medicine and basic research.
Additional note: Coils in the plastic model (model in the linked Youtube video) draw in ferro-magnetic objects like iron pellets and once the objects are drawn in currents to the electromagnetic coils are turned off via an electrical circuit and as pellets have momentum already achieved by prior attraction to the coil, they continue to travel along guided by the walls of the plastic tube. This process is done repeatedly at both coils in order to keep the pellet propelling along. Technically your plastic tube setup will only need one coil with a strong enough magnetic field or a small enough pellet, but adding more coils give better energy efficiency and fewer kinks to the motion of the pellet. (That is if you disregard the energy costs of additional material)