[TowerTalk] Baluns! Ack!
g3rzp at g3rzp.wanadoo.co.uk
Wed Nov 9 09:16:36 EST 2005
Further to K9YC's comments on ferrite toroids..
They would probably do OK as chokes with the coax wound around them. I've used old TV line output tranformer cores as 'line isolators' quite successfully, winding the coax around the ferrite. About 10 turns of RG58 at well below its bend radius (naughty!)
gave a series impedance of around 500ohms resistive over the HF band. I suppose a transmission line balun could be made with these rings, but you would need to be careful at any power and check the losses first. But as for acting as a true transformer where the energy is transferred through the magnetic field, then they would probably be OK at the proposed world wide 135kHz band.....but not above.
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