Full 4-Step Contacts in 60 Seconds
4× Pileup Speed with Single-Carrier (240 vs 60 QSOs/h)
0.0 dB Power Penalty
LQ8 is a next-generation amateur radio weak-signal protocol that re-engineers message packing using variable-length prefix codes over the exact, battle-tested FT8 physical transport layer (8-GFSK, 50 Hz, −21.0 dB SNR). Complete full contacts with bidirectional grid, report, and 73 confirmation in 4 transmissions (60s vs 75–90s) and achieve 240 QSOs/h in pileups (4× over single-carrier FT8, 2 QSOs every 30s) with 0.0 dB RF power penalty (scaling to 480 QSOs/h dual-carrier).
1-on-1 Contacts
Completes full contacts in 4 transmissions (60s vs 90s canonical or 75s with RR73 in FT8) via an optimal 4-step exchange (CQ → CALL → REPORT+73 → 73) at full reference sensitivity.
- 4 transmissions vs 5–6 in FT8
- 60 contacts/hour (vs 40–48 in FT8)
- 0.0 dB power penalty
High-Density Pileups
In continuous pileups, slot 3 overlaps with new callers on split frequencies, completing 2 QSOs every 30 seconds (240 QSOs/h, 4× over single-carrier FT8) on a single carrier with 0.0 dB power penalty (vs 60–120 QSOs/h in FT8 Fox & Hound with severe power split), scaling to 480 QSOs/h dual-carrier!
- 240 QSOs/h (1 carrier, 50 Hz, 0 dB)
- 480 QSOs/h (2 carriers, 100 Hz)
- 0.0 dB power penalty
100% Proven Physical Layer
Identical 8-GFSK modulation and LDPC(174,91) channel coding as FT8. Zero changes required to radios, soundcards, or antennas.
- Exact 8-GFSK 50.0 Hz physical transport
- Standard & 13-char extended callsigns
- Unique Costas sync for protocol isolation
LQ Family (LQ4, LQ2, LQ16)
Seamlessly adapts to high-speed VHF/contesting (LQ4: 30s QSO), ultra-fast bursts (LQ2: 15s QSO), and extreme deep-signal DX (LQ16: −24.0 dB SNR).
- LQ4: 30s 4-step QSO (83.3 Hz)
- LQ2: 15s 4-step QSO (166.7 Hz)
- LQ16: −24.0 dB DX (25.0 Hz)
Operation & Ecosystem
Get on the air with native mobile software, dedicated band plans, and seamless electronic logging compatibility.
qFT8
Native mobile transceiver application supporting LQ8 alongside other existing digital modes. Operate weak-signal digital modes anywhere from your Android device.
Proposed Operating Frequencies (Experimental HF Allocations)
Dedicated 3.0 kHz channel sub-allocations for LQ8 in experimental mode across seven primary HF bands to ensure clean, interference-free weak-signal evaluation.
To evaluate weak-signal performance in clean RF spectrum without interference, on-air operations are conducted on dedicated 3.0 kHz Upper Sideband (USB) channels across seven primary HF bands: 40m, 30m, 20m, 17m, 15m, 12m, and 10m. Each dial frequency represents the base carrier frequency of a standard 3.0 kHz Upper Sideband (USB) channel (e.g., 14.084 MHz spans audio offsets from 14.0840 to 14.0870 MHz). Multiple stations operate simultaneously within each 3.0 kHz window on separate audio subcarrier offsets.
These selected bands provide optimal, noise-free propagation environments: 30m is a narrow-band WARC allocation with no voice phone operation allowed by international law; 17m and 12m offer contest-free WARC spectrum, while 40m, 20m, 15m, and 10m provide expansive, quiet digital allocations well separated from their respective voice phone segments.
| Band | LQ8 (3 kHz USB) | FT8 (Ref) | FT4 (Ref) |
|---|---|---|---|
| 40m (7.0 MHz) | 7.084 MHz | 7.074 MHz | 7.0475 MHz |
| 30m (10.1 MHz) | 10.146 MHz | 10.136 MHz | 10.140 MHz |
| 20m (14.0 MHz) | 14.084 MHz | 14.074 MHz | 14.080 MHz |
| 17m (18.1 MHz) | 18.106 MHz | 18.100 MHz | 18.104 MHz |
| 15m (21.0 MHz) | 21.084 MHz | 21.074 MHz | 21.140 MHz |
| 12m (24.9 MHz) | 24.925 MHz | 24.915 MHz | 24.919 MHz |
| 10m (28.0 MHz) | 28.084 MHz | 28.074 MHz | 28.180 MHz |
Note: Additional allocations (including 80m, 160m, 60m, and VHF/UHF bands) will be officially assigned in upcoming phases as coordinated with international band plans.
ADIF Electronic Logging & Award Compatibility
Standardized electronic logging format for LoTW, QRZ.com, eQSL, ClubLog, and amateur radio software suites.
Logging and Submitting LQ8 QSOs: Practical Guidelines
Under the ADIF 3.x specification, exporting contacts using standard mode <MODE:4>DATA with <SUBMODE:3>LQ8 allows electronic loggers and signing tools to record and process contacts without mode-rejection issues.
When submitting logs to QRZ.com Logbook, ARRL Logbook of the World (LoTW), eQSL.cc, and Club Log, contacts logged under DATA are recognized under standard digital categories for DXCC, WAS, VUCC, WAC, and WPX award credits (using local software mode mapping if needed).
Formal submission to the ADIF Working Group is underway to establish dedicated native enum tokens and drop-down menu support across all logging applications.
Standard ADIF Specification
All protocols in the LQ digital mode family follow the Amateur Data Interchange Format (ADIF 3.x) guidelines under mode DATA with protocol submode identifiers.
Instant Platform & Award Compatibility
Online logbooks accept contacts under digital mode categories for digital awards with standard submode tracking.
Standard Mode & Submode Tags Reference:
| Protocol | ADIF Mode Tag | ADIF Submode Tag | Standard Comment Tag |
|---|---|---|---|
| LQ8 | <MODE:4>DATA |
<SUBMODE:3>LQ8 |
<COMMENT:34>LQ8 digital mode - https://lq8.org |
Example Standard ADIF QSO Record (.adi):
<STATION_CALLSIGN:6>HB9IPH
<MY_GRIDSQUARE:4>JN47
<CALL:5>TU2TU
<GRIDSQUARE:4>KL22
<QSO_DATE:8>20260815
<TIME_ON:6>002500
<BAND:3>30M
<FREQ:9>10.146000
<MODE:4>DATA
<SUBMODE:3>LQ8
<RST_SENT:3>-03
<RST_RCVD:3>+05
<COMMENT:34>LQ8 digital mode - https://lq8.org
<EOR>
POTA Exception: When exporting logs for the Parks on the Air (POTA) app, contacts must be set to mode <MODE:4>MFSK with no submode tag, as POTA requires MFSK for log acceptance.
How is the 60-Second QSO & Pileup Speed-Up Achieved?
By replacing repetitive rigid exchanges with variable-length prefix codes, 24-bit/16-bit collision-resistant hashing, and multi-station response frames, while guaranteeing full mutual exchange: both Maidenhead locators and signal reports are conveyed, with reciprocal 73 acknowledgments confirming reception.
FT8 Standard
LQ8 Standard
FT8 Pileup
LQ8 Pileup
Strategic Roadmap & Ecosystem Milestones
Our clear trajectory toward global amateur radio standardization, multi-platform applications, reverse beacon reporting, and electronic logbook integration.
Phase 1: Mathematical Specification & Reference Library Completed
Full definition of the variable-length Huffman prefix trees, 104-character Varicode, CRC-14/CRC-24Q algorithms, and the open-source C++20 reference library (lq_lib) with verified test coverage and exhaustive cross-platform validation.
Phase 2: Native Mobile Applications & Field Validation Active / Current
Comprehensive over-the-air field validation. Native mobile implementation in qFT8 for Android (qft8.com) and development of native iPhone / iPad (iOS) transceiver applications for portable and field-day operation.
Phase 3: Adoption by Wide Applications & Spotting Networks Active / In Progress
Adoption by wide applications such as WSJT-X, JTDX, N1MM+, Ham Radio Deluxe, and Log4OM, as well as live reporting through the PSKReporter service, Reverse Beacon Network (RBN), and HamSpots.
Phase 4: Formal ADIF Standardization & Dedicated Logging Ecosystem In Progress
Formal submission of LQ8 enum token to the Amateur Data Interchange Format (ADIF) Working Group (complementing existing 100% compliant <MODE:4>DATA + <SUBMODE> export). Dedicated native drop-downs and 1-click cloud sync integration across third-party logging suites, QRZ.com Logbook API, ARRL Logbook of the World (LoTW / TQSL), eQSL.cc, and Club Log.
Phase 5: Introduction of LQ4 (High-Speed Profile) & Protocol Expansion Future Roadmap
Following broad operational adoption of LQ8, introduction of LQ4 — a high-speed contest and VHF/UHF extension that delivers double the QSO throughput at double the bandwidth (4-GFSK, 83.33 Hz bandwidth, 5.04 s transmission in 7.5 s UTC slots). LQ4 is to LQ8 what FT4 is to FT8: by combining the 4-GFSK 7.5-second physical transport layer with LQ's 4-step Huffman prefix exchange, LQ4 completes full confirmed QSOs in just 30 seconds (versus 45 seconds in FT4) with zero SNR penalty relative to FT4. Phase 5 also encompasses coordinated expansion to additional amateur bands (including 160m, 80m, and 60m) as well as extended speed profiles (LQ16, LQ2).
Technical Specifications & Library
Formal academic specification, open-source reference implementations, interactive physical layer explorer, and bit-level message inspection tools.
Formal Specification Paper
Comprehensive paper covering physical layer modulation, variable-length Huffman prefix codes, Varicode, and protocol state machines.
Open-Source Reference Library (lq_lib) — C++20 & Pure C API
High-performance, zero-allocation C++20 and pure C99/C11 reference implementation supporting all LQ message encodings, GFSK continuous-phase audio synthesis, 2D STFT waterfall Costas synchronization, LDPC(174,91) Normalized Min-Sum codec with >95% automated test coverage and parallel multi-candidate demodulation.
Interactive Physical Mode Comparison
Explore the primary weak-signal standard (LQ8) and extended modes (LQ4, LQ2, LQ16).
Completes full 1-on-1 contacts in 4 transmissions (60s vs 90s in canonical 6-slot FT8 [1.50×] or 75s with RR73 [1.25×]) at full reference sensitivity (-21.0 dB SNR) in identical 50.0 Hz bandwidth, and scales to 240 QSOs/h in continuous pileups (4× over single-carrier FT8, 2 QSOs every 30s, up to 480 QSOs/h dual-carrier).
- 4-Step Full Exchange: 60s vs 75–90s in FT8 (and 240 vs 60 QSOs/h in continuous single-carrier pileups) with complete grid and report delivery.
- Zero SNR Penalty: Exact -21.0 dB sensitivity in 50.0 Hz bandwidth (+3.5 dB over FT4).
- 24-bit Hashes: Full CRC-24/Q (16.7M bins) preventing collisions.
- 13-char Callsigns: Extended compound callsign support (vs 11 chars in FT8).
- 104-char Varicode: ~17.2 chars/frame (+32.3% character throughput gain vs FT8).
Complete Bit-Level Serialization Inspector (All 13 Message Types)
Select any structured message type to inspect its binary bitfield, packed hex, and computed CRC-14 parity.
Physical Channel Tone Modulation
Continuous-phase 8-GFSK frame structure with Costas synchronization arrays and LDPC(174,91) coded data symbols in 50.0 Hz bandwidth.
Community Support, Clubs & DXpeditions
Recognized and supported by amateur radio clubs, DXpeditions, awards programs, and operators worldwide.
Clubs & Organizations
Radio clubs, contesting groups, and emergency communications teams experimenting with and adopting LQ digital modes.
- No entries listed yet — submit yours below!
DXpeditions & Activations
DXpeditions, IOTA, SOTA, and POTA operators leveraging high-throughput multi-station response frames to clear pileups rapidly.
- No entries listed yet — submit yours below!
Operators
Individual radio amateurs featuring LQ8 on their QRZ.com profiles, club rosters, and participating in award tracking.
Get Listed or Contact Us
Are you a club, DXpedition organizer, software developer, award manager, or ham who includes LQ in your QRZ bio? Reach out via our contact form to be featured here or to get in touch with the project team. To report bugs or submit feature requests, visit our GitHub Issues tracker.