Jim, Ham radio regulations (Part 97) differ quite a bit from unlicensed regulations (Part 15)...
Jim Thompson wrote: <snip> > a) explain how they knocked the side lobes down so they didn't have > unwanted emissions outside the band. Your answer here very likely > has the word "filter" in it, but then I'll just ask you for the > mfg/model # of same, so I can verify its claimed performance. Under part 97.305, amateur radio stations are allowed to use spread spectrum in the 13cm band 2390-2450 MHz. The signal has to be 802.11b, not 802.11g encoded (OFDM is not Spread Spectrum). Amateurs are allowed to use up to 1 watt without automatic power control and up to 100 watts with APC. There is NO limit on antenna gain. The ARRL bandplan is a suggestion, not an FCC requirement. Amateurs can operate on channels 1-6 using part 15 equipment. Typically hams use channel 5 or 2432 MHz as a center frequency to avoid interfering with amateur satellite transmissions near channel 1 or 2400-2410 Mhz. Furthermore, by picking channel 5, you have 18 Mhz above and 42 Mhz below center frequency for the +/- 11 Mhz signal to fall into. Part 97.307 describes the spurious emissions requirements. >From what I can tell, their setup could have met these requirements. > b) explain how they transmitted their HAM call sign (perhaps they set > the ESSID to it, but this wouldn't fulfill the requirements of Part 97) Amateur stations using 802.11b must identify every 10 minutes according to Part 97.119 b(3). ASCII is a recognized code. Setting the SSID to callsign1-callsign2 in the peer-to-peer mode is enough for ID. However, it is also acceptable to send identification in the text of the message, so that anyone with a normal 802.11b card can read the identities of the transmitting stations. I believe that if they followed either of these methods, their setup would have met the regs. > c) send along the call sign(s) used during this experiment, so the > FCC can pull their tickets. Please tell me where you think they broke any regulations? Their setup seems to use the minimum required power required to maintain the link. The high gain dishes minimize interference with others using the same band. But out of curiosity, I too would like to know their callsigns and would be interested in knowing if they met the part 97 logging rule of their contact. <snip> > They deemed it reliable because they wanted to. Did they put any > load on the network? Many people will misinterpret the results, > and clamor for 125 mile links with no other requirements than "line > of sight" and "big ears". For the reasons I've shown, and others, > while you might be able to "show" this in a "demo", its both illegal, > and it doesn't (nee: can't) work correctly. Give these guys a break. These guys are hackers. Who says it has to be stock software. They should have been able to hack the retry timer value in the firmware. For a valid contact on ham radio, they have to exchange callsigns and a signal report. There is no requirement to have a network load to make a contact. <snip> 73, Konrad Roeder, WA4OSH North Bend, WA
