Usable frequency ranges, depending on the application:
broadband transformers: 1 – 30 MHz
RFI / EMI / CMC suppression: 1 – 20 MHz
An impedance> 1000Ω (for operating frequency) is sufficient for most applications. The coils should be made with very good quality RG-58 coaxial cable. Any high quality RG-58 coaxial cable can allow 1kW power in 160 / 80m. For higher bands> 10MHz, it is recommended to use the additional teflon insulated coaxial cable to keep the losses low.
According to the table below, for Wurth Elektronik 74270191 (our case), between 6 turns (80/40 / 20m) and 10 turns (160m) would be enough to obtain an impedance of at least 800-1000Ω, from 1.8 – 14MHz .
|Dimensions||6.1 × 6.1 × 2 cm|