jaw@ames.UUCP (James A. Woods) (07/26/85)
# fools speed ahead that amazing telebit/dca 10kbit modem sure seemed like a minor miracle (infoworld, 7/22), so i called telebit for the technical dope. if the literature is to be believed, bad lines don't really faze the thing. i'm sure a few usenet sites with $2300 would jump for it. is it time to ring the death knell for CCITT modems, which, because of noise and gross fallback strategies, never reach their max throughput? hmm ... "packetized ensemble coding...inventor lists airport metal detector, invention of packet switching in 1964, and co-founding of equatorial communications (your friendly neighborhood spread spectrum service) among his credits". no slouch here. dca stock (telebit is private, but marketer dca is public) has risen to around $30 of late, from about $22 a few weeks back. oh, the dope -- - 512 carrier freqs. each modulated with either 6-bit or 4-bit QAM, or 2-bit QPSK, depending on SNR. - adaptive duplexing, to take advantage of the one-way burst nature of most traffic. - fallback in decrements of < 100 bps. (successive rate halving of the v22 standard is the real killer on dialups.) - bell 103, 212a, and hayes command language compatibility - call (800) telebit ames!jaw