Quad Antenna Calculators

Original programs were written in GW Basic. For detailed information, please refer back to the orignal articles:

New Quad studies:

All articles by L. B. Cebik, W4RNL.

Calculated fields left blank don't apply to that type of antenna, or were not studied in the original article. Spreader lengths are adjusted for wire diameter.

Desired frequency: mHz
Wire diameter: AWG size:
Antenna type:

Calculated values:

For best results, -4.5< < -2

Quad Dimensions:
wavelengths inches meters
Wavelength 1
Wire diameter
reflector side
reflector spreader
reflector perimeter
reflector-driver space
driver side
driver spreader
driver perimeter
driver-1 director space
first director side
first director spreader
first director perimeter
1-2 director space
second director side
second director perimeter
total boom length
Approximate Resonant Feedpoint Impedance = Ohms
Approximate Free-Space Gain =
Approximate 2:1 VSWR Bandwidth = % of Design Frequency, mhz
Approximate >20 dB F-B Ratio Bandwidth = % of Design Frequency, mhz
Approximate Rate of Gain Change = dB per 1% of Design Frequency