The MFJ 266C HF/VHF/UHF antenna analyzer is a versatile and powerful tool for RF diagnostics and measurements. Some of its key features and specifications include:

Frequency coverage: Covers HF and VHF/UHF amateur and commercial frequencies, from 160 meters through 6 meters, the aircraft band, 2 meters, 1-1/4 meters, 70 cm, plus VHF/UHF commercial 2-way frequencies. Does not cover frequencies between 65 and 108 MHz or 230-308 Megahertz.
SWR, impedance, and complex impedance measurement: Displays SWR 1:1 to 9.9:1, impedance magnitude, and complex impedance (resistance and reactance) simultaneously with the operating frequency.
Capacitance and inductance measurement: Can quickly find values for unknown capacitance in pF or unknown inductance in uH at RF frequencies.
Frequency measurement and field strength readings: Accurate 500 MHz counters with a choice of 1 kHz or 100 Hz resolution, and high-resolution digital field-strength meter for measuring the relative intensity of incoming signals.
Built-in interference detection: Can detect the presence of an offending signal, display its severity, and identify the operating frequency.
Powerful tunable signal source: Generates a +2 dBm CW carrier (about 2 mW) across nearly the entire tuning range for driving mixers, low-power amplifier stages, or filters, and checking antenna patterns.
User-friendly layout: Ergonomic design with the Type N antenna connector positioned on top of the case and everything else clearly marked on the front panel.
Rugged construction: Made with a solid aluminum case, solid-state band switching, robust internal construction, and solid-state LCD display for minor bump and drop protection.
Battery or adapter power: Can be powered by four internal AA alkaline batteries or optional 12 V DC/110 V AC adapter.