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Comet Antenna Analyzer


CAA-500MARKII SWR/Impedance Analyzer

Highly accurate analog cross needles display SWR and impedance simultaneously.

Full color TFT LCD display screen provides graphic and numerical SWR along with total impedance with R and X values.



Automatically graphs the SWR on the LCD display.   Choose any one of the pre-set amateur band frequency ranges and press the sweep button…in about 30 seconds the SWR graph is completed.


Choose the band,  manually set the band-width you desire, then manually sweep the chosen frequency range.


Should you want to make an adjustment to the antenna length, the position, height above ground, a gamma match adjustment, etc… you can overlay multiple manual sweep results in 5 different colors!  Instantly graph and see exactly what happened after each adjustment!


Range: 1.8 – 500MHz (including 222MHz band)

  • RF output level:  0dBm 1 mW

  • Measured SWR Range:  Analog meter 1.0 – 6.0:1 , LCD display 1.0 – 9.9:1

  • Impedance measurements: 12.5-300 ohms

  • Reactance range:  0 – 500 Ohms (absolute value) 1.8 -190MHz

  • Battery indicator and selectable Auto-Power-Off timer

  • Operates up to 9 hours continuous using six AA Alkaline or NiMH cells (not included) or use an external 8-16VDC 200ma power source (DC cable included)

  • Internal trickle charger option when using NiMH batteries

  • Size: 3.5 x 7.75 x 2.65 inches (overall)

  • Weight: 2 lbs 2 oz with alkaline batteries installed

  • Available from all major Ham Radio Dealers in the US

The CAA-500MarkII is the primary tool for any antenna adjustment or diagnostic project.

Specifications subject to change without notice

CAA-500 manual sweep mode


Press the “Sweep Center” button and the analyzer automatically sweeps the entire pre-set band that you have selected, in this case the 2M band.

CAA-500MarkII manual sweep mode


In the manual sweep mode, the center frequency (in this case 146MHz) and the bandwidth (in this case +/- 3MHz) 143-149MHz have been set manually.

The SWR is graphed by manually turning the frequency knob.

Adjustments to the element length, gamma match, height above ground, location, etc… can then be made, and by turning the frequency knob a new SWR graph in a new color, is overlaid onto the original graph to illustrate the change to SWR.

Each adjustment can then be graphed as may times as desired, in up to 5 different colors.


Padded nylon soft case protects the CAA-500 or CAA-500MarkII  SWR/Impedance analyzer from damage.

  • 1/4″ foam padding
  • Nylon Tricot fabric resists tearing
  • Front panel protective panel Velcros in place (not shown)
  • Shoulder strap and belt loop included

The CAA-500/CAA-500MarkII are sensitive test instruments, the CAA-5SC protects the case and meter lens from damage caused by accidents or everyday wear and tear.