Note
QST, Jan 1982, p, 100.
The Icom IC-AT100 and IC-AT500 are fully automatic antenna tuners designed to provide rapid and precise impedance matching across the HF amateur radio bands.
Key Characteristics:
– Fully Automatic Operation: When connected to a compatible Icom transceiver (such as the IC-740 or IC-751), the tuner automatically selects the correct frequency band via the transceiver's band-selection signals.
– Rapid Tuning: The units utilize an advanced motor-driven system to adjust variable capacitors and inductors, typically achieving a match in under 3 seconds.
– Multiple Antenna Ports: Both models feature four separate antenna connectors on the rear panel. These can be preset to specific bands, allowing for automatic antenna switching when the radio's band is changed.
– Safety & Protection: The tuners include a "Wait" circuit that prevents the transceiver from transmitting while the tuner is in motion, protecting both the radio's final transistors and the tuner's internal components.
– Versatile Matching: Designed to handle an SWR of up to 3:1, they ensure that the transmitter always sees a stable 50-ohm load.
– Through/Auto Modes: A front-panel switch allows the user to bypass the tuning circuit ("THRU") or engage the automatic matching system ("AUTO").
Specifications
Note: Specifications below apply to both models unless otherwise (noted.)
– Frequency Coverage: 3.5, 7, 10, 14, 18, 21, 24.5, and 28 MHz
– Input Impedance: 50 Ω
– Matching Range: 16.7 Ω to 150 Ω (SWR 1:3)
– Input Power Capacity: 100 (500) watts PEP (Continuous)
– Minimum Tuning Power 10 (50) watts
– Tuning Accuracy: SWR 1.5:1 or less
– Tuning Time: Approx. 3 seconds (Max 7 seconds)
– Insertion Loss: Less than 0.5 dB (after tuning)
– Antenna Connectors: Input: SO-239 / Output: SO-239 x 4
– Operating Temp: −10∘C to +60∘C
Power Requirement: 13.8V DC ±15% (Negative ground), 117V or 230V AC
Power Consumption: Max 1.0A (at 13.8V DC), Max 30VA (at AC operation)
Cost:
IC-AT100, $350.00
IC-AT500, $550.00
