The balun transforms an unsymmetrical signal at a 50 Ω source impedance into a galvanically isolated symmetrical signal at 120 Ω impedance in a wide frequency range.
Thus measurements on symmetrical quadripoles which have an impedance of 120 Ω can be done using regular measurement devices which work with a 50 Ω impedance usually.
For instance the response characteristic of VDSL2+ lines can be determined with the SYS 9223-120B. Also measurements according to CISPR 17 (resp. DIN EN 55017) can be performed on components or filters.
Besides this 120 Ω model there are broadband baluns available for 100 Ω, 135 Ω and 150 Ω from the SY9223 series.
| Frequency range: | 9 kHz – 60 MHz |
| Insertionloss: | 10 dB |
| Flatness: | <±1 dB |
| Input connector: | BNC |
| Inputimpedance: | 50 Ω unsymmetrical |
| Input impedance matching: | >15 dB @ 9 kHz – 60 MHz |
| Output connectors: | RJ45 Pin 4+5; 4 mm banana female |
| Output impedance: | 120 Ω symm. |
| Max. input power: | 1 W |
| Test voltage primary-secondary: | 200 V DC |
| Groundconnector: | 4 mm socket |
| Dimensions: | 130 x 105 x 48 mm |
| Weight: | 470 g |
| Housing material: | Aluminium |