The following calculations should be helpful for building a magnetic loop antenna. I make no claims to understanding the math and took it straight from the spreadsheet at Steve Yates AA5TB's spreadsheet.
I've tested this against AA5TB's spreadsheet and the values appear to match. Please let me know if you encounter any bugs!
| Parameter | Value | USC Unit | Metric Unit |
|---|---|---|---|
| Design frequency: | MHz | ||
| Loop diameter: | feet | m | |
| Conductor diameter: | inches | mm | |
| Added Loss Resistance: | milliohms | Caused by poor joins, etc. | |
| RF Power: | Watts |
| Parameter | Value | USC Unit | Alt Unit |
|---|---|---|---|
| Wavelength | feet | m | |
| Efficiency | % | dB | |
| Bandwidth | kHz (-3 dB) | ||
| Loop circumference | ft | m | |
| Loop area | ft2 | m2 | |
| Radiation resistance | mΩ | ||
| Loss resistance | mΩ | ||
| Total loss resistance | mΩ | ||
| Loop inductance | microhenries | ||
| Inductive Reactance | Ohms | ||
| Distributed capacitance | picofarads | ||
| Quality factor | |||
| Tuning capacitor | picofarads | ||
| Capacitor potential | Volts | ||
| Minimum plate spacing | inches | mm |
