Contents
JG25: speed and evidence #
Website evidence review: 6 September 2026.
JG25 is designed to move useful data efficiently through ordinary FM voice radios, including the microphone/pre-emphasis and receive de-emphasis paths. The current published material supports waveform specifications and scoped decoder results. It does not establish a current-release file-transfer speed across those paths.
Waveform rate is not file throughput #
The JG25 v0.3 specification defines seven raw rates from 1,200 to 2,400 bit/s. JG2400 therefore means 2,400 raw bits per second. Payload framing, acquisition, error correction, turnarounds, acknowledgements and retries reduce the rate of useful file bytes delivered.
The implemented wire format has one bearer envelope per PHY frame, with full acquisition and a protected header on each frame. JSQ services provide their own reliability. The separate compact link layer, 32-frame link ARQ window and multi-frame burst optimization in v0.2 were not adopted; v0.3 preserves them as historical proposals in Appendix C.
What the recorded-audio study reports #
The JG2400/F0 phase-body decoder handoff reports CRC-valid, byte-exact recovery of 37 of 37 complete JG2400/F0 real-radio fixtures: nine held-out August body-CRC failures and 28 existing successes. All passed on the first timing hypothesis.
That result has a specific scope:
- It tests the JG2400/F0 body decoder against a recorded corpus, not a fresh over-the-air delivery campaign.
- The handoff explicitly says this decoder was not yet called by the runtime at that stage.
- One additional fixture had a clipped preamble and was excluded from the 37 complete fixtures. The report separately describes finding and decoding its frame in the untouched continuous recording.
- Other modes, FEC profiles, current-release end-to-end reliability and file goodput are not established by the 37/37 result.
- The document's later integration-gate checklist describes required future tests, not completed results.
This is encouraging decoder research. It should not be advertised as a 100% reception rate or a demonstrated transfer-speed advantage over AX1200.
What would support a microphone-path speed claim #
A publishable comparison should use the same payloads and radio path for JG25 and AX1200, and record:
- Exact app builds, radio models, bandwidth settings and audio interface.
- Transmit entry point (including microphone pre-emphasis) and receive audio exit point.
- Mode, FEC, acquisition settings, drive levels and receiver processing.
- Payload size, successful whole-file verification, elapsed wall-clock time, retries and failed attempts.
- Delivered goodput in useful file bytes per second, plus the number of trials and range of results.
Report ordinary successful runs and failures together. Keep synthesized-audio tests and recorded-audio replay results separate from live radio measurements. No comparable current-release goodput measurement was available in the material reviewed for this website update.
Source provenance #
The protocol snapshots and decoder handoff were read from the OpenJSQ application repository's claude/shared_files_integration branch, pinned at commit 09c350bac83dfec0f8a6245256d9f3ec3f01fb80.
The copied decoder handoff is docs/JG2400_F0_PHASE_HEAD_HANDOFF.md, Git blob a3767d84d9b972f703ef540a5da63a1b60d9135f. Its experiment was based on claude/jg25_fm at 500ceb2; its claims retain that historical scope. The source recording corpus is not included with this website.
The reviewed virtual-audio bench findings for build fde52e7 reported transmit underruns and corrupted cross-station frames. That session verified sender-side and single-instance UI, but could not establish successful inter-station mail, file or relay delivery. Its screenshots remain useful as interface examples only.
The populated Chats, Files, Network and Inbox images on the website are screenshots of the running application, captured during an example net between three test stations linked by a virtual audio cable. The displayed traffic, paths and statistics are captioned as examples and are not presented as performance measurements. The more complete website operator guide is retained because the integration-branch copy lacks its JG25 quick start.