The ACC server itself must be started on a computer or laptop. In addition to this laptop, additional hardware is needed, such as the monitors for displaying the traffic light. There are many different combinations of components that are dependent on your needs. Therefore, no general statement can be made about which hardware components you need exactly. If necessary, I am happy to advise you.
On a computer or laptop, the ACC server must be started, which provides the controller and the clients. This can be run on all common Windows and Linux systems. Basically, no more computers are needed now.
Usually, you can connect multiple monitors to one computer. You can configure the display to show the control on the first monitor and the client on the second monitor.
If you would like to use multiple clients, it is recommended to use a second computer that is only responsible for these clients. This second computer must be connected to the first computer via a network. This is possible via cable, or otherwise via WLAN.
External speakers might be required to provide the shooter with loud enough horn sounds.
Instead of a computer or a laptop you can use a Single-board computer. This offers all functions of a computer but "slimmed down", however it is more than sufficient for the ACC Archerytimer. I recommend the Raspberry Pi, which is relatively cheap to buy (about € 35.00).
It should be noted that while most of the hardware is splash-proof, heavy rain is relatively probable in outdoor tournaments. Therefore, it makes sense to have a deployable umbrella ready.
I also offer compilation and configuration of a complete hardware setup for you - individually according to your requirements.