Quote:
Originally Posted by WM6
Agree. Ferrite toroid can be proper solution. As proposed, depend on amplifier output impedance (usually between 4-8 Ohms) you wind primary first with resistance equal (or a little more) to tech. spec. for speaker driven by amplifier, then test secondary first by 10 turns and measure peek-to-peak voltage at about 50% of amplifier power. Out of results you can calculate total secondary turns to about 50 - 60V pp no more.
As I say, I prefer air cored coil antenna (unshielded of course), but for distances of 10-30m ferrite cored antenna can be usable too.
Proper distance from detecting place is achieved when antenna polarization (changing orientation of antenna in different directions) can give you very clear differences in signal strength on field strength meter (receiver).
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Thanks WM6.
I want to receive the signal with 2 loops with 90 degrees phase shift between them and to measure the phase shift.
