11. They are all topologically equivalent to toroids . 12. Baluns can be made using ferrite toroid cores or even from the coax feedline itself. 13. This design is based on a toroid ( the same shape as a doughnut ). 14. The toroid should be repositioned or covered with tape or something to blunt its edge. 15. The output stage is top left, the output chokes are the two yellow toroids underneath. 16. In this context a toroid need not be circular and may have any number of holes. 17. The first three categories are all convex, whereas Stewart toroids have polygonal-faced tunnels. 18. They source toroids from Nuvotem Talema in Ireland since H & F ceased trading in 1993. 19. Many other lower symmetry toroids can also be constructed by removing a subset of these dissected components. 20. Supercoiled DNA forms two structures; a plectoneme or a toroid , or a combination of both.
