Ferrite rods can be used on TX as long as the ferrite does not saturate. This means low power. I like to think of the high permeability as a "shrinking of space". Indeed this is how I visualise ferrites work on RX.
Being a loop, they can be very narrowband, but will work when frequency is fixed such as with WSPR or FT8.
I have no idea what the "gain" is, nor have I any idea of the ferrite material that I used. It is some years since these experiments were carried out. The results astounded me.
See https://sites.google.com/site/g3xbmqrp3/antennas/ferrite_tx
See also https://en.wikipedia.org/wiki/Permeability_(electromagnetism)
No comments:
Post a Comment