Multimedia without hum

The audio output (2 RCA jacks) my DVB-T tuner (3 pol. Schuko plug with earth) is about a 5 m long stereo cable (4 RCA plug) with an auxiliary input (2 RCA jacks) of my hi-fi amplifier (2 pol. plug without ground). To suppress power Bumm (50 Hz + 1 harmonic 100 Hz) and to protect the devices by galvanic isolation, I bought the "Hum Destroyer" from MicroHD.

Of course I have the silver colored housing (aluminum, sandblasted) using the 4 black Phillips screws immediately screwed to ventilate the Geheiimnisse the circuit. On a rectangular, provided with silkscreen board contains 4 isolated jacks and 2 unshed miniature transformer. The case is not connected to ground. Because of the symmetrical construction of bi-directional operation is also possible. Because of the frequency limit (15 kHz) of transformers is not possible video use.