The QMX+ Internal ATU / Battery / Speaker Mod by AC8L is an all-in-one internal expansion system for the QRP Labs QMX+ that adds a compact automatic antenna tuner, internal lithium battery support, and integrated speaker functionality in a rugged portable format. Originally designed by Sardar AC8L, the project combines portability and field convenience into a single integrated package for QRP operators. Additional technical specifications, firmware information, and open-source project files are available through the AC8L GitHub Repository, with active development discussions and community support found on the QRP Labs Groups.io Community.

These kits are intended for builders with varying soldering experience levels, from complete DIY assembly to nearly fully assembled units. All kits include the PCB set and required components unless otherwise noted.

General Product Overview:

The AC8L ABS V2 system transforms the QMX+ into a highly portable self-contained field radio by integrating:

• Internal automatic antenna tuner (ATU)

• Internal speaker system

• 3-cell 18650 lithium battery support

• Compact integrated form factor

• Open-source hardware and firmware ecosystem

• Community-supported ongoing development

Designed specifically for portable QRP operation, POTA, field deployment, and emergency communications, the ABS V2 provides a clean internal solution without requiring multiple external accessories.

To keep shipping costs down: 18650 batteries are user supplied and not included in the sale.

95% Build Kit – Fully Assembled & Programmed — $235.00

This premium version is nearly ready to install and operate. All SMD and through-hole components are professionally installed, and the PIC controller is pre-programmed and tested.

Features:

• Fully assembled PCB set

• PIC pre-flashed with firmware

• ATU, speaker, and battery boards assembled

• Minimal final assembly required – you will need to solder four headers to your QMX+

• Ideal for operators with limited soldering experience

Perfect for users who want the convenience of a near turnkey solution while still enjoying the flexibility of the open-source ABS platform.

75% Build Kit – Through-Hole Assembly Required — $210.00

All surface-mount components are professionally installed, and the PIC controller is pre-programmed. The builder completes the remaining through-hole component installation.

Features:

• All SMD components installed

• PIC pre-flashed

• Through-hole parts require soldering

• Excellent balance between cost savings and simplified assembly

Recommended for builders comfortable with standard through-hole soldering but who prefer to avoid fine-pitch SMD work.

50% Build Kit – Partial Assembly Required — $195.00

This version is intended for intermediate builders who are comfortable installing larger components and relays.

Features:

• PIC pre-programmed

• Builder installs:

• Through-hole components

• Large SMD capacitors

• 15 Mosfets & 1 Diode

• Relay components

• Lower assembly cost with more hands-on building experience

A great option for hobbyists who enjoy the assembly process while avoiding PIC programming requirements.

0% Build Kit – Complete DIY Kit — $175.00

The full builder experience. All components are included, but no assembly or programming has been completed.

Features:

• Includes all SMD and through-hole components

• PIC requires programming by the builder

• Complete assembly required

• Lowest cost option

• Maximum flexibility for experimentation and customization

Ideal for experienced kit builders and experimenters who want the full hands-on construction experience.

Important Notes

• The ABS V2 project remains in active community development.

• This ATU is based on the ATU-100 architecture and experiences many of the same operational limitations associated with that tuner design.

• Due to tuning performance limitations on the higher HF/VHF spectrum, it is recommended that the ATU be bypassed or taken out of line when operating on the 10 Meter and 6 Meter bands.

• Performance characteristics and firmware improvements continue to evolve through ongoing community testing and experimentation.

• Builders are encouraged to review the AC8L GitHub documentation and QRP Labs Groups.io discussions before assembly and operation.

• The ABS V2 is manufactured for use with an external RF jumper connection between the QMX+ and the ATU assembly using SMA connectors.

• Advanced users may choose to modify the system to internally reroute the RF signal path and bypass the external SMA jumper arrangement; however, components and parts required for internal RF routing modifications are not included with the kit.

• As with many experimental/open-source amateur radio projects, some tuning and operational experimentation may be required depending on antenna type, operating band, and station configuration.