Toroid 2643625002
Ferrite Toroid, type 43 material.
This toroid is ideal for QRP (low power) ununs, e.g. 49/56/64:1 for EFHW antennas.
Outside Diameter= 0.625 in / 15.875 mm +/- 0.375 mm
Inside Diameter = 0.311 in / 7.9mm +/- 0.25 mm
Height = 0.563 in / 14.3 mm +/- 0.35 mm
References:
- Colin MM0OPX's video (https://www.youtube.com/watch?v=nZ-G4hJCTSM)
- Colin MM0OPX's spreadsheet
https://docs.google.com/spreadsheets/d/13kImt_tkezngocXQ5tOBDkTscp5F-RFD/edit#gid=2134716366 - KD7QOW 95% efficient EFHW transformer https://www.youtube.com/watch?v=fNqv0rUlMPU
- https://owenduffy.net/blog/?p=12642
