The TBST-86/49/45/1 is a shielded tent, designed to suppress interference from ambient noise during EMC pre-compliance measurements. With a size of 86 cm x 49 cm x 45 cm, it can accommodate any Tekbox pre-compliance test equipment such as LISNs or TEM-cells.

The shielded tent is composed of two layers of conductive fabrics. It is supported by rigid aluminium profiles. The filter panel at the side provides a 240V/10A AC filter, two 240V/10A DC filter and four coaxial feed through adapters with screw caps. The access opening is sealed with conductive Velcro tape.
 

Example: Conducted noise measurement

The dark green graph below shows the measured spectrum of a non-powered DUT in a CISPR 25 conducted noise measurement setup. The DUT connects to the TBOH01 5µH LISN with a very short supply cable (10cm). The cable between LISN and DUT and the DUT PCB itself already pick up significant ambient noise from AM and FM broadcast stations.

The light green line shows the results of the same arrangement, with the DUT and LISN placed inside the shielded tent.
 
The graphs below show the conducted noise spectrum of the powered DUT. In the unshielded set up, all emissions, except the first harmonic of the DUT and conducted noise between 40MHz and 50MHz, are hidden under the ambient noise level. An accurate measurement would not be possible without a shielded set up.