Evaluation of 28MHz Inverted V Antenna

Smith Chart Evaluation

• The dots on the Smith chart are close to the center, confirming a good match.
• It is located near the center at 28.080 MHz, the best matching point.
• It shifts to the upper right (inductive) when going to 28.5 MHz and to the lower left (capacitive) at 27.99 MHz.

Evaluation of 28MHz Inverted V Dipole Antenna

VSWR and return loss

• Marker 1 (28.080MHz):.
  • VSWR: 1.298 → Very good
  • Return Loss: -17.753 dB → good matching
• Marker 2 (28.500MHz):.
  • VSWR: 1.440 → Slight increase, but within practical range
  • Return Loss: -14.886 dB → Acceptable
• Marker 3 (27.990MHz):.
  • VSWR: 1.300 → Good
  • Return Loss: -17.683 dB → good matching

Rating
The VSWR is low throughout the entire 28 MHz band and the return loss is sufficiently low to provide good matching.
The best matching is at 28.08 MHz in particular.

• 28.080MHz (Marker 1): 28.080MHz (Marker 2): 28.080MHz (Marker 3)
  • Impedance: 1.0 to 2.038.7 - j1.86Ω(almost resistant)
  • A little low for 50 ohms, but good matching
• 28.500MHz (Marker 2): 28.500MHz (Marker 2): 28.500MHz (Marker 2)
  • Impedance: 1.0 to 2.050.6 + j18.4Ω(reactance increased)
  • Close to 50Ω, but slightly inductive (inductive)
• 27.990MHz (Marker 3):.
  • Impedance: 1.0 to 2.040.1 - j6.44 ohms(slightly capacitive)
  • Low, but can be adjusted to get closer to 50 ohms.

Rating
The frequency is adjusted close to 50 Ω near the center frequency.
The frequency range is slightly inductive at high frequencies and slightly capacitive at low frequencies.