When using ball machines to train students one must also be able to understand the different ball machine parts that make up the ball machines for tennis as this is also a good training ground for them in understanding how the machine works for them. It will help develop the students’ eye for detail recognition and help him improve his technical skills. Furthermore, it will also help being knowledgeable in the different ball machine parts so that when there is a need to purchase certain parts for the tennis ball machines, distinguishing them will be very easy. Below are some of the common parts of a tennis ball machine that one must be accustomed to.
The Feed Control. The feed control is a built-in specification of the tennis ball machine. It basically controls the speed of the ball feeding that enhances the ball recognition skill of the students who are taking the drill. The feed control is one of the most important parts of the ball machine as without it, getting the drill to work will prove to be difficult.
The Battery Pack. While it may seem pretty shallow, the battery pack of the tennis ball machine happens to be one of the most essential parts of the whole machine especially if one purchases the portable types of tennis ball machines. 
There are certain ball machines for tennis that do not include extra battery packs in their packages so it is suggested that before purchasing a tennis ball machine to do check whether the package can include an extra battery pack, especially if the one that is already attached to the machine is not rechargeable. That way you get the best deal for your money.
Controling the Remote. Majority of the tennis ball machines that are now available in the market come with remote controls to make using the ball machines easier and coming up with drills for the students easier. These remote controls however also have a lifespan and are very sensitive to damage. 
So do make sure that when purchasing a tennis ball machine, the remote control that comes along with it is also part of the warranty of the whole machine or at least has spare parts that can easily be bought in tennis stores should it be damaged. If not, do ask the store where you plan to buy the machine from if they also have repair shops that can look into damaged remote controls of ball machines for tennis. It is very important to take care of the remote controls as much of the functioning of the ball machines will depend on the buttons and controls of this small device.
When purchasing tennis ball machines, be sure to check out the different ball machine parts first. Especially when you plan to buy used tennis ball machines. It is important to make sure that each part is still functioning very well or is still in good condition as you would want to be able to get a good deal for your money and at the same time make full use of the product that you are buying for your tennis training needs. When you are knowledgeable in the different ball machine parts for tennis, getting a good ball machine that will work for you will be easier to find.