LDG AT-100 PRO II – Automatic Antenna Tuner


The LDG AT-100 PRO II covers 1.8-54 MHz and features a two-position antenna switch allowing instant switching between two antennas. It requires just 1 watt for operation but will handle up to 125 watts, making it suitable for everything from QRP to a typical 100-watt transceiver.


Like most LDG tuners the AT-100 PRO II operates automatically, beginning a tuning cycle whenever the SWR exceeds a preset limit. It also features LDG’s advanced memory tuning, providing 2,000 memory locations; when tuning near a previously used frequency it will recall the settings for nearly instant tuning. It learns your favourite frequencies and bands as you use it.

It will match dipoles, verticals, inverted Vees or virtually any coax-fed antenna. With an optional LDG balun, you can also use long wires or antennas fed with a ladder line. It handles 100 watts SSB or 50 watts FM/Digital when used with a solid-state transceiver; vacuum tube transmitters cut the power ratings about in half.

Please Note: When used with radios like the IC-7300, FTDX10 or TS-890 in bypass mode the tuner will pass 70 MHz with minimal loss but will not tune at that frequency.

  • 1 to 125 watt power range (SSB and CW), 100W on 6M
  • Easy to read LED bar graph display for RF power, SWR and status
  • Over 4200 memories for instantaneous band changing
  • Two position antenna switch. Separate memories for each antenna
  • Tuning Time: 0.5 to 6 seconds full tune, 0.2 sec memory
  • Selectable User Parameters: Auto/Semi, 125/12.5 watt scale, power save and more
  • 1.8 to 54.0 MHz coverage. Built-in frequency sensor
  • Tunes 6 to 1000 ohm loads (16 to 150 on 6M)
  • Interfaces with Icom and Yaesu with optional cables
  • Small Size Enclosure: 7.5″ (D) x 5.5″ (W) x 2.0″ (H)
  • Weight: 1.5 lbs

Additional information

Weight 1 kg