Kenwood TS-590S

A 100-watt HF/6m transceiver - and one that hams still argue about whether it's "discontinued" or "in production."

Overview

The TS-590S is an HF/50 MHz transceiver covering 160 through 6 meters. It arrived after what Kenwood's own development team called "a long interval" since the company's previous HF rig. That phrase comes straight from Kenwood's engineering notes, where the team admitted they "felt desperately sorry each time a customer asked us, at the annual ham fairs, when Kenwood's new HF transceiver would be available." It's a compact base station that transmits at a full 100 watts on SSB, CW, FSK, and FM. AM output is derated to somewhere in the 5-25 W range according to at least one spec sheet.

The power output isn't what makes the TS-590S interesting. 100 watts is table stakes in this class. The receiver architecture is the draw. Kenwood built the TS-590S around an advanced down-conversion design with a narrow first roofing filter and a dedicated first mixer. The company claimed this combination delivers superior dynamic range against adjacent off-frequency signals. Every manufacturer makes that kind of claim, but this one has test data behind it. Rob Sherwood published a full lab test of the radio in December 2010, and the results put it in competitive territory for its price bracket.

The radio also inherits a lot. Kenwood was the first manufacturer in the amateur radio market to deploy DSP-based AGC at the IF stage, starting with the TS-870S. The TS-590S takes that DSP approach to the next level. Owners consistently describe the menu system as straightforward and the display as very clear. They also call the built-in tuner useful, not an afterthought like the tuner in some entry-level rigs.

Production status is a mess to pin down. Universal Radio lists the TS-590S as "Discontinued! Replaced by the TS-590SG," while eHam's product page still says "Product is in production." That contradiction likely reflects a stale database entry. The SG variant is the current model; the S is the original. No exact production start or end dates appear in the available documentation, so the h1 omits a year range rather than guess.

Key Features

Down-Conversion Receiver with Narrow Roofing Filter

Most modern HF transceivers use an up-conversion architecture. They mix the incoming RF up to a high first IF, which makes filtering easy but can degrade dynamic range. The TS-590S goes the other direction. It's an advanced down-conversion receiver with a narrow first roofing filter and a dedicated first mixer. Radioworld UK credits that combination with "superior dynamic range" and effective management of unwanted adjacent off-frequency signals.

This is what separates the TS-590S from lesser rigs on a crowded band. eHam's review page describes the radio as significantly reducing interference from unwanted signals "that would be hidden to lesser rigs." For contesters and DXers working split frequencies in a pileup, that matters.

Advanced DSP and IF AGC

The TS-590S uses advanced DSP technology. Kenwood introduced DSP-based AGC at the IF stage with the TS-870S, and the TS-590S is the next generation of that technology. The practical benefit is cleaner AGC behavior on strong signals. The receiver doesn't pump or breathe the way analog AGC circuits can when a loud station suddenly appears. Combined with the roofing filter, the DSP gives operators a suite of interference-fighting tools that would have cost thousands more a decade earlier.

Built-In Automatic Antenna Tuner

The internal tuner covers a range of 16.7 to 150 ohms. That's wide enough to match most practical HF antennas without an external tuner. Owners on hamradio.co.uk specifically call out the built-in tuner as a strong point, alongside the straightforward menu and clear display. A random wire or a multiband vertical with imperfect resonance on some bands can be a rough load, and a tuner that handles a 3:1 or 4:1 mismatch without complaint is a real convenience. It also saves rack space and cabling in a compact station.

Frequency Stability and the SO-3 Option

Stock frequency stability is rated at ±5 ppm. That's adequate for SSB and CW work in normal conditions. For operators who need tighter stability, such as digital modes, weak-signal work, or operation in wide temperature swings, Kenwood offered the SO-3 TCXO as an option, which tightens stability to 0.5 ppm. That's a meaningful upgrade for JT65 or similar modes where a few Hz of drift can cost you the contact.

USB Connectivity and Computer Control

100 Watts on HF and 6 Meters

Output is a full 100 watts on SSB, CW, FSK, and FM, with AM limited to a range reported as 5-25 W. That AM figure comes from a single source and should be treated as approximate. AM is rarely the primary mode for a radio like this, and Kenwood's documentation doesn't emphasize it. The 100-watt output on 6 meters is worth noting because 6m is a band where every dB helps during sporadic-E openings. Current drain is rated at 20.5 A or less on transmit and 1.5 A or less on receive with no signal, so a reasonably sized 13.8 V supply will handle it without strain.

Historical Context

Kenwood launched the TS-590S after a significant gap in the company's HF transceiver lineup. Loyal customers had been asking pointed questions at hamfests. Kenwood's own development team acknowledged this directly, writing that they felt "desperately sorry" each time someone asked when a new HF rig would arrive. The TS-590S was the answer.

Universal Radio lists the radio as discontinued and replaced by the TS-590SG, though at least one dealer database still shows it as in production. That discrepancy almost certainly reflects a stale listing rather than any ongoing manufacturing. No exact production start or end dates are documented, so treat any specific year range with caution.

Collectibility & Value

The TS-590S is too new to be a true vintage collectible, but old enough that prices have settled into a comfortable range for buyers who want serious HF performance without paying current-model prices. A used example listed on a Russian classified site carried an asking price of 85,000 rubles, and a YouTube seller offered one at $950. That listing is undated, so treat it as a rough reference point rather than a current market value.

Condition matters with a DSP-based radio. Jahnke Electronics, a dealer that specializes in used amateur gear, describes its typical TS-590S stock as "fully checked out and aligned." It notes that units come with a 5-foot power cable, microphone, manuals, and the original double box set. The same dealer claims its radios "transmit at a full 100 watts," which is the kind of claim a buyer should ask to have verified before committing.

Owner sentiment runs warm. One eHam reviewer called the TS-590S "the second best radio I have ever owned," placing it behind only a 32-year-old TS-830S. Another described it as a well-regarded transceiver with a straightforward menu, built-in tuner, and very clear display. The TS-590S has a reputation as a dependable, capable rig that does the fundamentals well without a steep learning curve.