Acom 500S Amplifier Unboxing

It is important to know who we are dealing with. ACOM amplifiers are made in Bulgaria. May I add: proudly made in Bulgaria. Yes, to some still locked in the Cold War mentality, ‘Made in Bulgaria’ may sound worse than made in China. Unfortunately, some prejudices are hard to overcome. But when it comes to technology, engineering and innovation, rest assured that some of the former Communist countries are now on the very forefront of manufacturing.

For a few obvious reasons: they take technical studies seriously. An eastern European engineer is a proper engineer. There are no multiple choice answers at the faculty of engineering. Also, while communism failed to ‘produce prosperity’, manufacturing was always a core state activity. People were poor, but hardworking and skilful. Think of the labour base Australia had in the 50s and 60s.

Today, Bulgaria is part of the European Union. Thanks to foreign capital, affordable industrial real-estate, an abundance of energy resources, and a skilled workforce, it is an ideal manufacturing country with access to almost half a billion consumers in a 2000km radius.

ACOM is a high-tech engineering and production company located in Sofia, a part of a Corporate Group of three integrated companies. The other two group companies are MILARA (metal manufacturing) and VOLACOM (solution provider to avio / industrial users). Since 1988, ACOM develops and produces HF power equipment and short-wave systems for network radio communications. The product portfolio includes power amplifiers, antenna tuners and switches, Ethernet remote control devices, automatic XCVR commutators, and custom-made products.

ACOM products are designed for the amateur radio, commercial, and government markets. With a work force of over one hundred, and thanks to its extensive expertise in developing and manufacturing high-end HF power equipment, ACOM is a profitable business.

And to state the obvious: the amplifier business is a niche business which requires more than just capital, people and manufacturing lines. Today, only a handful of makers in the world are capable of making amplifiers of a commercial quality for the amateur market, and ACOM amps are the very top tier.

Personally, I am very proud to represent ACOM as an authorised Australian dealer. It goes without saying that if you are in the market for a new amplifier, ACOM should be your first choice, and DXing your only choice of supplier.

Over the next couple of weeks, I will do my best to introduce to you the entire ACOM amplifier range, providing the facts from a users perspective – the only perspective that really matters to you.

All the amplifiers and accessories are now in stock, in our Sydney shop, ready for delivery.

If you wish to discuss any particular item straight away, feel free to reach out.

And now the Unboxing…….

The ACOM 500S is a state of the art LDMOS linear power amplifier that covers all amateur bands from 1.8 through 70.5 MHz and puts out 500 Watts (PEP or digital).

It is the smallest amplifier in the range, and also the newest model, released this year.

Weight: just 7.8 kg. 29 x 25 x 14.5 cm.

The Acom 500S comes triple boxed. The first glimpse of what is awaiting in the box is a Quality Inspection Certificate, noting that the amp has passed a 24 hour work test. Reassuring!

Taking the amp out of the plastic wrap, reveals the amazing ‘top grade hi-fi amp (think B&O)’ finishes of the front panel, cover and back plate. The grained jet-black anodized front is simply stunning – immediately, it becomes obvious this is not an amp to be placed in a garden shack or taken on an expedition! Definitely exceeding the expectations of the most pedantic buyer.

The amp comes with a generously long power cable, with a power plug to be installed by the owner. The main switch is located at the back, with the on button on the front, requiring a press-and-hold action. A second later, you are greeted with ‘TEST’ in CW. Love it! (There is also an ‘AR’ on power off).

Again, used to large amplifiers, I am still blown away by its size. Unboxing should not be rushed – so take a moment to admire the high resolution colour display before going further.

On the back, you will find two antenna sockets, key in and key out RCA connectors, and two serial ports for CAT / RS232. Straight forward, no-fuss arrangement. As with all modern radios, the operating manual is a downloadable pdf file. It is obvious: 500S is an amplifier made for a user who expects both looks and performance, no tune, auto band switching amplifier delivering a solid 500 Watts on all modes. Turn it on, use it, have fun.

Is 500 Watts of output power enough for you? If it is, then 500S could be the way to go – especially if you can’t stand noisy fans, heat, high voltage and manual tuning. In stock, ready for delivery. You can email us at for a price and we’ll get back to you immediately.

Article by Nick ( VK2DX ) –