The presented circuit is used to test ordinary fluorescent lamps. This circuit also has a mains voltage indicator that makes it possible to detect any drops in the 110 V and 220 V mains, which can be a cause for the incorrect functioning of a lamp. For lamps with powers other than 20 W, the circuit can be changed by simply changing the ballast and starter. The voltage indicator remains unchanged. The circuit works as follows: connected to the 220 V network, the neon voltage indicator lights come on. With FS2 connected to the base, the fluorescent lamp is connected to the electrical outlets (15/20 W), one fixed to the device and the other to the flexible unit.
