Implementation evidence
Results for hfmodem's four modes. RF reception, gateway transfers, independent bench decodes and simulations are identified separately.
PACTOR
Confirmed outbound mail delivery through WS8EOC over PACTOR-3. Four messages received through KB5LZK over PACTOR-1, with a normal session close.
| Result | Evidence and conditions | Record |
|---|---|---|
| PACTOR-3 outbound mail delivered | W9SSJ via WS8EOC; receipt confirmed by the operator | Message 9WQNVWBDLVOY |
| Four messages fetched; session closed normally | KB5LZK; PACTOR-1 throughout the exchange. Message IDs: JWKY65C2OZES, FP8L9JM4Q2L3, YQKB3UDBH1KG, J7VQ9ZYDX9L5 | Station log |
| PACTOR-1 payload delivered byte-exact to the peer's host | Virtual audio with Sailer's (HB9JNX) hf-pactor software; frozen-counter and altered-payload negative controls | Bench record |
| PACTOR-1 rate reduction in both directions | Bench tests cover local fallback and requests for the peer to halve its rate | Test suite |
| PACTOR-2 SL1 entry frame decoded | Independent monitor on the bench | Station bench record |
| PACTOR-3 payload prefixes decoded at all six speed levels | Reference decoder over virtual audio; idle/CR normalization, wider lock search at SL1/2 | Bench record |
| PACTOR-3 grants and entry packets received | Station summary of 68 attempts: four reached a grant and two reached a grant plus a decoded entry packet. Separate 40 m and 80 m records contain banner and packet payload fragments | Station logs |
PACTOR-3 mail delivery is demonstrated through one gateway; speed-level coverage and reliability across gateways remain open. PACTOR-2 evidence is at the bench level. The association between status-byte bits 4–5 and a PACTOR-3 grant is an inference from two gateways; see capability negotiation.
Mode guide · ARQ implementation
VARA
Mail reception through K0SI and confirmed outbound delivery through KB8AY. Multiple deliveries confirmed by the operator.
| Result | Evidence and conditions | Record |
|---|---|---|
| Three complete message files and one partial file saved | K0SI; four mail offers, BW2300, 40 m, 7101.8 kHz center, 10 W; acknowledged close | Station log |
| Secure login accepted and outbound body accepted | KB8AY; BW2750, 40 m. CMS challenge answered, proposal V15F3FF1BAF4 accepted with FS Y, body followed by FF, session closed with FQ | Station log |
| Outbound message delivered to its internet address | KB8AY; BW2300, 40 m, 7101.5 kHz center; gateway acceptance and destination receipt confirmed | Message NL03TXWQ8SGL |
| Multiple outbound deliveries confirmed | Receipt in Gmail confirmed by the operator; gateway and session details unspecified | Operator report |
| All 41 connect tones recovered | Michigan KiwiSDR recording of a KC9GHZ call on 7103.5 kHz | Remote recording |
The secure-login and confirmed-delivery records used the registered third-party SID [Pat-1.0.0-B2FHM$]. They establish the challenge-response and B2F exchange under that client identity. Inbox confirmation establishes delivery of the named message through KB8AY.
Mode guide · Session implementation
ARDOP
The besra implementation has transferred mail in both directions, in separate gateway sessions.
| Result | Evidence and conditions | Record |
|---|---|---|
| Message fetched | WW2MI gateway session | Station log |
| Outbound message delivered | WW2MI gateway session with delivery confirmation | Message 2KX2HWM919HR |
| Three messages fetched in one session | W6IDS gateway session | Station log |
| Bidirectional cross-decode across all 59 frame types | ardopcf reference codec | Bench record |
Reference-codec and recording-dependent tests report skips when those inputs are absent. pytest -rs lists them.
sabir
Sabir is experimental and unfinished. Its protocol and wire format are subject to change. Beacons have been decoded from two remote receivers; session traffic and host integration are exercised through simulated channels.
| Component | Demonstrated behavior | Evidence |
|---|---|---|
| Beacon reception | 40 m transmissions decoded from public receivers 103 and 302 miles away | Remote recordings, decoded with hfmodem |
| ARQ and retransmission | Selective codeword acknowledgement, timeout retry and payload resegmentation without duplicate delivery | State-machine tests and channel simulations |
| Turn-taking | Sender handover, receiver turn requests and turn recovery | State-machine tests; bidirectional Watterson channel simulation |
| Disconnect | Host-requested close, remote close and abort; stale-session controls rejected | State-machine and host-interface tests |
| Host interface | Single framed-CBOR connection per station; bidirectional payload transfer | Paired servers over simulated channels |
| Data profiles and object transfer | OFDM and narrow FSK profiles; connectionless object framing and integrity checks | Error-free and Watterson channel simulations |
The radio entry point transmits beacons and prepared datagrams. Connecting the two-way session engine to live audio and PTT remains incomplete. Carrier groups masked during a session remain masked; re-probing is unfinished.
Mode guide · ARQ implementation · Host interface
Source records
RF transfer results come from station logs and operator receipt confirmations. The delivery references are message 9WQNVWBDLVOY for PACTOR-3 through WS8EOC and message NL03TXWQ8SGL for VARA through KB8AY, plus message 2KX2HWM919HR for ARDOP through WW2MI. Named reference decoders and remote receivers provide the independent observations identified above. Simulation results use two instances of hfmodem.