the Ted transponder antenna is not TSO (certified)
The 104-12 series transponder antenna consists of a unipolar antenna with a sphere at the apex to provide an actually shorter antenna and to create a factor of reliability and safety.
Powered by a 50 ohm coaxial transmission line, the antenna offers a voltage standing wave ratio of 1.2: 1 at 1090 MHz and less than 2: 1 at 1030 MHz.
The antenna features an omnidirectional vertically polarized radiation pattern when mounted on the underside of the aircraft fuselage.
It is readily mounted using an "O-ring", single hole bulkhead sealed with a female BNC type connector.
VSWR standing wave ratio:
1.2: 1 at 1090 MHz
2: 1 at 1030 MHz
In a transmission line, the VSWR (Voltage Standing Wave Ratio) or ROS (Standing Wave Ratio) is a parameter that indicates the ratio between the maximum value and the minimum value of the voltage module along the line.
RG 400 or RG 58 coaxial cables work fine, just make sure you have a BNC connector