"See the Quality,
    Feel the Power" 

These Alpha/Power (ETO) amplifiers contributed the expressions brick-on-the-key maximum legal-power and all modes, no time limit to the lexicon of amateur radio. They pioneered the no-compromise desk top amplifier, hands-off no-tune-up operation, full break-in (QSK), standard 160 meter coverage, and microprocessor-controlled automatic bandswitching, tuneup and remote control.

Alpha/Power (ETO) also has pioneered realistic buyer protection with long term limited warranties (never prorated and now an unequaled four years), and the money-back guarantee.

Alpha/Power (ETO) has been the performance, innovation, and quality leader for 31 years. Would-be competitors have flattered us by imitation time and again. But they never catch up, because Alpha/Power's amateur radio linears share the advanced technology, manufacturing capability, and commitment to customer satisfaction that have made us a leading worldwide supplier of RF power amplifiers to billion-dollar corporate leaders in industry, science and medicine.

  The Products

power in less than one second. It can be fully remote controlled by a terminal or small computer, even by radio or wire modem from hundreds of miles away.

You'll find the Alpha/Power 99 hard to believe.  You may think that a heavy-duty linear specified, designed, tested and fully backed by Alpha/Power for less than $4000 is a misprint. Other amplifiers of comparable power do sell for more, but none beat the 99 's brute ruggedness.

Facts & Caveats for Amplifier Buyers
A high performance amplifier is a significant investment. But while foresight is the only sure cure for buyer's remorse, it's often hard to get accurate information.

The capabilities of an RF power amplifier can be specified accurately and thoroughly. Most of the manufacturers we know are honorable people, but we nevertheless see some ads and promotional literature containing claims and implications that range from ambiguous to absurd.

It is our intention to continually update this pamphlet, offering suggestions and information to help you make informed amplifier comparisons and a satisfying buying decision.

EVALUATING & COMPARING POWER AMPLIFIERS
Manufacturers' literature generally reveals most of what you need to know-through what it does and doesn't say. You sometimes need to read between the lines.

POWER RATINGS: RF output is the key parameter defining amplifier capability. The output power rating should be stated unequivocal (References to DC or PEP input are irrelevant and serve only to confuse.) Since the FCC's power rules are based on peak RF output, we believe that every amplifier ought to incorporate a  respectable peak-reading RF wattmeter.

An amplifier's robustness-its ability to tolerate hard use and even abuse - is best indicated by a precise duty cycle specification. After all, surprisingly flimsy components can deliver 1.5 kW if the duty cycle is low enough.

Beware of ambiguous terms like heavy duty. Even continuous duty is misleading when modified by phrases like for 'x" minutes (which inherently defines intermittent duty) or in amateur service (which may imply 30% or even lower full-power duty cycle). Contrast that with the ALPHA 87A's simple, clear specifications: 1.5 kW PEP or carrier output, no time limit.

TRANSFORMER DESIGN AND WEIGHT provide a credibility check on power claims. Using as a reference a conventional transformer with E-I core laminations of common transformer steel, power output per pound of weight may be improved significantly by using a core grain-oriented silicon steel such as Hipersil® or Unisil®.  Further improvement results if the core is actually wound from a continuous strip of such steel. The following examples illustrate the difference.

Example #1: The ALPHA 76PA transformer uses a conventional, E-I steel core and weighs 45 pounds we rate it conservatively to power a well-designed grounded-grid amplifier to about 750 watts continuous carrier output (1.2 kW DC plate input).

Example #2: The ALPHA 87A and 99 transformers use much more expensive
construction - a core of tape-wound Hipersil® or Unisil® with triple-insulated windings for superb reliability. They weigh under 40 pounds, but are capable of delivering more than twice as much power as the 45 pound '76PA transformer: over 2.5 kW DC input for 1.5+ kW amplifier RF output with no time or duty cycle limit.  A conventional 76PA-type transformer capable of equivalent power would weigh roughly 65 pounds. These two examples should help evaluate other manufacturers' ratings.

FREQUENCY COVERAGE: If you're interested in the 10, 18, 24 and/or 28 MHz bands, be cautious. The FCC doesn't allow U.S. amplifiers to be operational on 24-29.7 MHz as shipped.  How convenient will it be to use a particular amplifier on these bands? Any manufacturer should be willing to tell you how complex it is to activate 24-28 MHz, and what performance is possible in each band. E.g., are full power, gain, and convenience available on 18 and 24 MHz? Unlike our 87A and 99 , some amplifiers require inconvenient and time-consuming re-tuning of input circuit to achieve full power when moving to and from the 18 and/or 24 MHz bands.