Toroidal cores are used in a wide variety of applications such as common- mode chokes , broadband transformers and baluns.
 
Type 61 mix toroid’s are suitable for the creation of a transformer for CobWeb antennas and other radio amateur applications.
 
Dimensions
35.55mm Wide
12.7mm Thick
23mm Hole
 
The type 61 ferrite is specifically useful as a common mode choke at the higher end of the HF bands.