We’ll cover selecting and installing 18650 batteries, understanding how battery capacity affects your total runtime, and choosing the right audio interface for data modes like JS8Call, Winlink, and FT8. Whether you’re preparing for field operations, off-grid expeditions, or emergency communications, this post will get your TX-500MP ready for reliable service.

Finally, please read through this entire post before unboxing your radio. It’ll save you lots of time and headaches as you get your radio ready.

First Power-On and Setup

Before operating the TX-500MP in the field, take a few minutes to get the radio set up. This will ensure it powers up safely and is ready to go before you head out.

• Installing the Batteries: You’ll need six flat-top 18650 lithium-ion cells for the BP-550 battery pack. These are very similar to the 18650 cells used in most headlamps or flashlights. Detailed instructions on selecting the correct cells and choosing suitable capacity can be found in the battery section of this post.
• Attach the BP-550: If the BP-550 battery pack was not attached when your radio arrived (mine was attached already), you’ll need to install it. Align the pogo pins on the BP-550 with the matching pogo pad connector on the radio, ensuring proper contact. Secure the pack using the supplied Allen head screws, tightening them to the torque specification listed in the user manual.
• Power On the Radio: To power on the radio with the BP-550 installed, there are two steps. First, locate the power button on the BP-550 itself, found beneath the table leg at the bottom of the BP-550 and radio. Press and hold it for about a second, or until the red LED illuminates. Immediately after, press and hold the radio’s own power button on the front panel until the display lights up. The TX-500MP should start normally within a second or two.
• Check Battery Voltage: From the main screen, scroll to the Voltage I/O menu and activate it. Verify the current battery voltage, and if you’re connected to external power, check both the load and incoming charge values displayed on screen. The radio provides real-time information for monitoring battery and input status. Anything below 10.5 volts indicates the cells need charging.
• Set Time and Date: To adjust the date and time, open the menu, scroll to the “Time” option, and set the clock and date values. This ensures accurate timestamps for manual QSO logging. I set my clock to Zulu time for consistency with standard radio logs.
• Perform a Receive Test: Connect an antenna, then tune to a known broadcast or amateur radio frequency and verify audio reception. FT8 frequencies are excellent for this, as their distinctive tones make them easy to identify and they are active on most HF bands.

Choosing the Correct Battery Type

One of the TX-500MP’s biggest strengths is its standby time. Even with modest 3500 mAh cells, the 3S2P configuration and ultra-low receive current consumption mean it can monitor frequencies, bands, or networks for days at a time without external power. This makes the TX-500MP exceptionally well-suited for field or extended deployments. Its wide DC voltage input also allows recharging from almost any DC source encountered in the field. By combining an ultra-efficient design, flexible charging options, and a generous onboard battery capacity, the radio can remain operational much longer than most operators would expect.

The TX-500MP is integrated with the BP-550 battery pack. The BP-550 uses standard 18650 lithium ion cells. You’ll need to supply these cells yourself, so keep in mind that only flat top cells fit correctly inside the pack. Button top 18650 cells are too long and will not seat properly in the battery bays.

The BP-550 holds six 18650 cells. Use cells of the same brand, capacity, and age to ensure proper balance and safety. Avoid mixing old and new cells, and never use damaged or rewrapped batteries.

Although lower capacity cells may seem like a great deal, their reduced capacity and often lower sustained discharge rating directly affect your radio’s runtime and voltage stability during transmit. Choose high capacity cells in the 3000 to 3500 mAh range for the longest operating time, and select cells with a strong continuous discharge rating, sometimes referred to as a high C rating. This minimizes voltage drop and heat buildup under load. I chose the LG INR18650 MJ1 lithium ion cells in flat top configuration. These cells offer an excellent balance of capacity and discharge performance, making them ideal for long duration field operations. Each cell provides 3500 mAh of capacity with a 10 amp continuous discharge rating, which supports the TX-500MP’s power demands without excessive heat or voltage sag. Their chemistry is well proven in demanding applications such as power tools and e-bikes, giving confidence in both safety and consistency. When installed as a matched set of six, they provide excellent runtime, stable voltage, and predictable behavior under load.table behavior under load.

When used with high capacity flat top cells, the BP-550 can deliver an entire day or more of continuous JS8Call activity, or several days of intermittent voice operation. It transforms the TX-500MP into a very efficient, fully self-contained field radio that can be charged directly from USB-C PD, or solar without adapters or proprietary cables.

Power Management and Charging

The BP-550 can be charged in two ways: through its USB-C PD port or through the DC input on the side of the battery pack. The DC input accepts 13 to 50 volts from a regulated power source or a solar panel.

Do not connect power to both the radio and the battery pack at the same time. When charging the pack, external power must go into the BP-550, not the DC jack on top of the radio. If you power the radio directly, the BP-550 will not charge.

Use a USB-C PD charger rated at 30 watts or higher for reliable charging through the USB port. For solar or DC input, connect power directly to the BP-550’s DC port. The internal charge controller manages charging and cell balancing automatically.

The USB-C Power Delivery port on the radio is only for recharging the BP-550 battery pack. Do not use this port as a primary power source while transmitting, as doing so can overload the charging circuit if the onboard batteries are not fully charged.

Data Modes and Audio Interfaces

There are two interfaces that I recommend for the TX-500MP. If you are on a budget and do not need the advanced features, the DigiRig is an excellent entry-level option. It has purpose-built cabling for the TX-500MP providing reliable connections for most data modes. The DigiRig does not solve the cable management problem, but it offers a simple and affordable way to get started with JS8Call, Winlink, or other soundcard-based modes. You’ll find the figuring here: https://digirig.net/product/tx-500-cables/ Just remember to use the dropdown box to select TX-500MP!

The second option is the LiNK500MP from DL4KA. The LiNK500MP combines a Robust Packet modem and an audio interface in one device. This means you can switch back and forth between Robust Packet and modes like VARA HF, JS8Call, or Winlink without changing hardware. It supports Robust Packet and HF APRS either through external software or in standalone mode using its internal TNC. The LiNK500MP also includes Bluetooth Low Energy (BLE), allowing a completely wireless connection for its Robust Packet modem across Android, iOS, macOS, Windows, and Linux. It also features an integrated GPS module accessible to the computer’s operating system, providing accurate time synchronization and position data for APRS, message logging, or other geopositioning applications. The LiNK500MP attaches directly to the top of the TX-500MP, and the integration is so seamless that it appears to be part of the original radio design. You’ll find the LiNK500M=1 640 ft 5,0394 in here: https://diy599.net/en/products/link500mp-tnc

CAT Control

The TX-500MP supports two different CAT configurations for computer control and logging software.

Kenwood TS-2000 Protocol (recommended for most software). This is the one you will most likely use for Winlink, WSJT-X, JTDX, or JS8Call. Select “RIG Type: TS-2000” in your logging or control software. Set the baud rate to 9600, data bits to 8, parity to none, and stop bits to 1. The radio uses the standard Kenwood TS-2000 command set including FA, FB, and MD commands.

Lab599 Protocol Option. The TX-500MP also supports the proprietary LAB599 CAT protocol. Enable this mode in the transceiver menu under “Enable the CAT protocol LAB599.”

Both modes provide full CAT control for frequency, mode, and PTT. The TS-2000 option offers the best compatibility with common software, while the LAB599 protocol provides more precise control and tighter integration with Lab599 hardware and accessories.

CAT Control with the DigiRig

The DigiRig enables CAT control and audio connectivity for the TX-500MP through a single USB connection. It’s a simple and affordable way to operate JS8Call, Winlink, or VARA HF without additional hardware. When ordering from the DigiRig website, be sure to select the TX-500MP cable set. It includes the correct GX16 connectors used on this model, which are larger than the GX12 connectors on the original TX-500 and not interchangeable.

The DigiRig setup uses the same CAT configuration described earlier under “CAT Control.” Once connected, select “Kenwood TS-2000” as the rig type in your software, assign the correct COM port, and you’re ready to operate.

CAT Control with the LiNK500MP

The LiNK500MP provides both audio and CAT control through a single USB connection, simplifying digital mode operation. It also supports Bluetooth Low Energy (BLE) for wireless operation on Android, iOS, macOS, Windows, and Linux.

To activate CAT control, power on the TX-500MP and press and hold the VFO knob for about three seconds. This hands control to the LiNK500MP’s USB interface. To return to manual tuning, press and hold the VFO knob again for three seconds.

The LiNK500MP uses the same Kenwood TS-2000 protocol as described earlier, so no additional setup is required. Its integrated design with the TX-500MP makes it ideal for a clean, cable-free field setup.

I have added a few screenshots of CAT configurations with Winlink, JS8Call, & JTDX/WSJT-X.

Internal GPS

Many Operators have asked about configuring the internal GPS of the. TX-500MP. This feature is not a standard feature of the TX-500MP itself. Rather, it is a feature of the LiNK500MP from DL4KA. Like the Icom IC-705, the LiNK500MP brings the GPS, audio interface, Robust Packet TNC, VFO dial, and Bluetooth BLE to the Lab599 TX-500MP. Despite the cost, I highly recommend the investment as it reduces the cable mess, and adds critical functionalities to this field ready radio.

Antenna Connections and Deployment

N-connectors maintain a constant 50-ohm impedance through the entire connection, reducing signal loss and minimizing VSWR at higher frequencies. They also have a lower insertion loss compared to PL-259 or BNC connectors, making them slightly more efficient for long coax runs or higher-power use. Another key advantage is that N-connectors are completely weatherproof when properly mated, unlike PL or BNC connectors that can allow moisture intrusion and corrosion over time.

For field use, this means you can safely operate in wet or humid conditions without worrying about water ingress affecting your antenna connection. The trade-off is that N-connectors are bulkier and less convenient for quick connect and disconnect, but they offer superior durability and performance in long-term outdoor environments.

I currently use RG-316 with BNC connectors and an N-to-BNC adapter for my TX-500MP. However, I am considering building a dedicated set of coax cables specifically for this radio, 10 to 20 meters of RG-316 with a BNC connector on one end and a right-angle N-connector for RG-316 on the other. I plan to keep the BNC connector on the antenna end because most of my antennas, such as those from N9SAB, are dipoles or off centre fed dipoles that use BNC connections. Since several of my other radios also use these same antennas, it makes sense to keep the antenna side of my coax cables standardized while tailoring the radio side for the TX-500MP’s N-connector. This approach maintains compatibility across all my radios while providing a compact, weatherproof, and purpose built feedline for field use.

Recommended Field Antennas for the TX-500MP

The TX-500MP has a built-in antenna tuner, which makes it possible to use broadband antennas for multi-band operation without external tuning hardware. Depending on how much weight I can carry and the type of stations I’m targeting that day, I usually choose between a few reliable options:

• Chameleon MPAS Broadband Vertical: A rugged and versatile vertical system that covers multiple bands without adjustment. It’s fast to deploy on open ground or beaches and performs well for DX or long-range contacts where low takeoff angles matter.
• N9SAB Off-Centre Fed Dipole: Offers multi-band capability with efficient radiation and minimal need for a tuner on most bands. It’s a great balance between performance and convenience, ideal when you can get the wire elevated in trees or on a mast.
• N9SAB End-Fed Half-Wave: Compact and lightweight, perfect for portable and stealth operations. It’s quick to deploy as a sloper or inverted-V and works efficiently across multiple bands when paired with the radio’s internal tuner.
• N9SAB Linked Dipole: Delivers resonant performance with no tuner required on selected bands. It’s the most efficient option for field operations when you have time and space for setup, offering strong signals and predictable SWR.

Each of these antennas complements the TX-500MP’s low power consumption and integrated tuner, giving a flexible mix of efficiency, coverage, and portability for any field scenario. You’ll find N9SAB antennas here: http://oh8stn.net/n9sab

LiNK500MP Integration and Features

The LiNK500MP from DL4KA is a purpose-built companion for the Lab599 TX-500MP, designed to simplify field communications while adding powerful digital capabilities. It mounts directly to the top of the radio, forming a compact, weather-resistant package that looks and feels like an integrated system.

The LiNK500MP serves as both a Robust Packet modem and a soundcard interface, eliminating the need for separate devices in your digital setup. It supports Robust Packet and HF APRS either through external software or completely standalone, using its internal TNC. This makes it capable of operating as a digipeater, gateway, or direct point-to-point link even without a computer attached.

For other modes such as JS8Call, VARA HF, and Winlink, the LiNK500MP acts as a standard audio interface. It connects to your computer via USB for a wired setup or through Bluetooth Low Energy (BLE) for a completely wireless link. BLE support extends across Android, iOS, macOS, Windows, and Linux, allowing seamless operation with laptops, tablets, and smartphones in the field.

An integrated GPS receiver provides precise time synchronization and position data directly to your computer or software, enabling accurate APRS reports, message timestamps, and geolocation functions.

The LiNK500MP also offers full CAT control of the TX-500MP over USB, allowing your software to manage frequency, mode, and PTT automatically. When CAT control is active, press and hold the radio’s VFO knob for about three seconds to hand control to the LiNK500MP; repeat the same step to return to manual operation.

Together, the TX-500MP and LiNK500MP form a self-contained, low-power digital communications platform that minimizes cables, reduces setup time, and delivers professional-grade reliability in the field.

Size Comparison

In the following image you can see the size comparison between the Lab599 TX-500MP and the Icom IC-705, Xiegu X6100, and Yaesu FT-817/818. The TX-500MP sits roughly in the middle of the group in height and width but stands out for its exceptionally slim design. The Yaesu FT-817/818 on the far left is the most compact in height but also one of the thickest, following a traditional brick-style form factor. The Xiegu X6100, positioned next to it, has a smaller front profile but a noticeably deeper body that makes it appear bulkier despite its compact face.

The TX-500MP, even with the LiNK500MP module attached, remains the thinnest radio of the group. Its flat, rugged chassis minimizes depth and bulk, making it easy to store and transport in a field pack. On the far right, the Icom IC-705 is the largest and deepest overall, offering a full-featured interface at the expense of portability.

Taken together, these comparisons highlight how the TX-500MP achieves a uniquely balanced design which is narrower, lighter, and more streamlined than the others, yet maintaining full HF capability and rugged durability. It delivers the best ratio of performance to portability among all four radios, making it an ideal choice for serious field operations.

Go Bag

I store the TX-500MP system in a Helikon Service Case from Helikon-Tex. Inside the bag I carry the TX-500MP with the LiNK500MP installed, a dipole or end-fed half-wave antenna, 10 metres of RG-316 coax, two common-mode chokes, and a few adapters. The Helikon bag features durable Cordura construction, padded compartments and a fold-out layout that makes it easy to carry a complete field station—everything stays organized and ready for deployment.

TX-500MP Videos

https://youtu.be/oQKY1BZIOwY

https://youtu.be/8B5sGxHY7tY?si=hFuGziRkfBMlI8cX

3 Days Off-Grid

This video is special as it demonstrates the true strengths of the TX-500MP. We spent three days out in Puolanka Finland at a cabin. The TX-500MP was operational the entire time, acting as our HF link to its world. There were three things setting it apart from more popular portable radios.

1. 18650 Lithium ion batteries as standard: The 18650 batteries are an excellent choice, rarely if ever seen utilised in the Ham Radio world. No proprietary batteries needed!.
2. 10 watts output without needing an external battery: As far as I know, there are no other portable HF radios which can run full duty cycle at their highest output setting, without requiring an external battery or power supply. The TX-500MP does this whether or not an external power supply is connected to the radio. This means a fully self-contained radio which doesn’t require we carry additional supporting gear (e.g., extra batteries) to the field.
3. TX and RX efficiency: At 100ma RX current draw, the TX-500MP is at or near the top of the low current consumption game. What most reviewers fail to mention is the TX-500MP is extremely efficient on TX as well. This combination of RX/TX efficiency allows this radio to operate actively for roughly a full day of data mode operation. If you’re focused on standby time, the 18650 batteries and the radios standby current consumption, helps this radio remain ready when you need it to be.

Final Thoughts

From a field operator’s perspective, the TX-500MP stands out as one of the most robust HF/6M transceivers, designed for real-world deployment. It is not just about its size or rugged construction; it’s about a mindset missing from other ham radio manufacturers, a mindset translating into operational efficiency in extreme environments.

The TX-500MP feels engineered for operators who move and deploy in unpredictable terrain. Its fully sealed aluminum chassis keeps out dust, moisture, and cold that would cripple other radios. The lack of unnecessary protrusions means it packs neatly into any ruck or go-bag. Its low current draw and generous battery storage lets you monitor the bands for days on modest battery power.

From a practical standpoint, its ergonomics are also deliberate. The front-mounted controls are easy to manipulate while the radio lies flat on a surface or hangs from a strap. The large, sunlight-readable display is visible even under Arctic glare or desert sun. Combined with the integrated BP-550 power pack, this radio behaves less like a “portable rig” and more like a self-contained communications toolset.

When paired with the LiNK500MP, the TX-500MP evolves into a complete data comms package capable of JS8Call, Winlink, Robust Packet, APRS, and voice without a tangle of cables or power adapters. It’s the closest thing to a tactical HF Radio in the civilian market, by balancing low power consumption, modular expandability, and field survivability.

For off-grid communicators, SAR teams, or expedition operators, the TX-500MP delivers a blend of endurance and capability that few radios can match. It was clearly designed by people who understand what it means for your life depends on your radio.

Alright guys: That wraps up this guide to the Lab599 TX-500MP. We’ve covered everything from powering up the radio for the first time, installing and choosing the right 18650 cells, power management and charging, CAT control setup, and digital interfaces like the DigiRig and LiNK500MP, to antenna connections, recommended field antennas, and portable storage options. My goal was to give you a practical, field-ready understanding of how to get the most from this radio.

If I missed something or you have a tip of your own, leave a comment below and I’ll do my best to update the post.