ACOM 2000A
$$$$$
| Frequency | 1.8-30 MHz: 160 through 10 meters (incl. WARC), fully automatic |
| Bands | 160m, 80m, 40m, 30m, 20m, 17m, 15m, 12m, 10m |
| TX power | 1500 W (1500 W PEP AND 1500 W continuous carrier - flagship honesty (the '2000' in the name reflects the design's reserve)) |
| Modes | all |
| Weight | 36.5 kg (80.5 lb) |
| rf in | SO-239 |
| rf out | SO-239 |
| amp keying | relay to ground (solid-state safe) |
| rs232 | RS-232 for remote control and diagnostics |
| rcu | Remote Control Unit connects up to 3m (10 ft) from main unit |
| ac power | multi-voltage 90-264V AC. Ships without plug (AOM-2000A) or with NEMA 6-15P 240V (AOM-2000A-240). No plug installed on base model. |
| power req | 90-132 / 180-264 VAC, taps 100-240 V, 50-60 Hz single phase; up to 3500 VA at rated output (from 200-240 VAC; low-tap mains cap output near 1000 W to hold 20 A) |
The tube amplifier with the convenience argument solid-state thought it owned: full legal limit continuously, automatic everything (band, segment, match) faster than you can look at it, and the 3:1-VSWR full-power tolerance that forgives antenna systems mid-storm. The detached control pod is the best ergonomic idea in amplifier history, and two affordable tetrodes split the workload and the retubing bill.
Flagship price for tube-era running costs: warm-up, fan noise, eventual retubing, and real mains demands travel with the wattage. 6 m is absent (the HF design predates the band's amplifier fashion), the automation's complexity is itself a service surface, and the step-start/protection sophistication demands the manual actually be read.
Still the reference automatic tube amplifier: a quarter-century after it invented the category, the 2000A's combination of continuous legal limit, sub-second automation, and mismatch tolerance keeps it on contest desks that could afford anything. Buy the 1000 to learn amplifiers; buy this to stop thinking about them.
The ACOM 2000A invented its own category: the fully automatic tube amplifier. Before it, kilowatt tetrodes meant a tune-up ritual at every band change; the 2000A's digital control system reduced the entire practice to nothing - band changes follow your transceiver in under a second, segment changes in a fifth of one, and a full impedance match completes in under three. The operator presses no switches and turns no knobs; the amplifier simply keeps up. A quarter-century later, that remains the category's defining demonstration.
The RF underneath is as considered as the automation: two 4CX800A tetrodes, grid-driven (ACOM's own in-house tubes since the 2024 sourcing switch), delivering 1500 watts PEP and - the flagship distinction - 1500 continuous, 'no mode limit' in the maker's own words, with measured intermodulation typically 40 dB down. The auto-tuner's deeper gift is mismatch tolerance: full rated power into 3:1 VSWR (2:1 on 160), which converts 'the antenna iced up mid-contest' from an emergency into a log entry. And the detached RCU - the entire user interface in a desktop pod the size of a paperback, the 36-kilogram RF deck banished up to three meters away on the standard cable (twenty with the extension) - remains the best ergonomic idea any amplifier maker has had. Contest stations have built operating positions around it since the late 1990s.
The honest bill: flagship money - the last confirmed US retail was $6,499, with the US channel currently in transition while UK supply runs normally - tube-technology running costs (warm-up, fans, eventual retubing - though the GU-74B's surplus pedigree keeps that civilized), real mains requirements, and no 6 meters, the design predating that band's amplifier fashion. It was, remarkably, the Sofia family firm's FIRST amplifier product, launched 1998; its junior sibling the ACOM 1000 delivers two-thirds the capability at a third the price for those willing to turn their own knobs - which is precisely the choice the 2000A exists to make unnecessary. The contest world's verdict is visible in its station-tour photographs: the little RCU pod, everywhere.