![]() It’s doable from an experimental point of view, but not practical even with modern radio equipment.įor those wondering what D-Dial is, you can check out magviz.ca or. If D-Dial were to run over radio, you would need 7 full duplex connections. Now with large ISP’s like Comcast, TCP/IP has long surpassed 300 baud-56k. AOL came into being and got the internet more exposure. When Bill Basham wrote D-Ddial, it was because a nurse lamented to him about the price of the hourly rates the big services like Compuserve and GEnie were charging at the time. When D-Dial first came on the scene back in 1984, Schools still used Apple ][ computers in the classroom. Nowadays, with robust networks, and the technical innovations of the last 40 years, it’s definitely time to update the protocols. Well, when those protocols were adopted in 1980, the internet, most of the large ISP’s of the time, and even D-Dial didn’t exist. Limiting it artificially wasn’t the idea, originally.Īs long as amateurs don’t cause interference, a deviation from the norm should be possible here and now. PS: Let’s don’t forget that certain things on the band plan have the nature of a recommendation.Īmateur radio is an experimental service, too. On the road, a broader FM signal is lesser prone to the doppler-effect, too. The old 25 KHz channel spacing allowed for more bandwidth, less interference and better signal/noise ratio. On 2m/70cm, the 12,5 KHz channel spacing did more harm than good. Why must channel spacing be reduced over and over again ? Unused repeaters are being enough there, already. The ham bands are being more and more abandoned, anyway. It’s just puzzles me why quantity always wins over quality for apparently no good reason. For native English speakers, at least.įoreign radio buddies may have trouble here, because of extreme lo-fi quality on shortwave.Īlas, the individuals in charge of those regulations were older men and either didn’t care or didn’t know. The reason we can still decipher things is because of the “error correction” of the human brain. ![]() So a single side band would make use of those ~5 KHz to improve audio quality.īecause, actual information of human speech lies within the higher frequencies.Įspecially with women and children being affected here. Rather than reducing the channel bandwidth, it would have been more appropriate to use these ~5 KHz for SSB. That new ~3 KHz channel limitation of the SSB era wasn’t very wise to begin with.īack in the AM days, ~5 KHz were being used (carrier+two side bands). Posted in News, Radio Hacks Tagged digital modes, fcc, ham radio, vlf Post navigation You know, just in case Thomas Dolby tells us that one of our submarines is missing. The 2200 meter band isn’t even 2.8 kHz wide to start with!Īll this talk makes us want to build something for the 2200 meter band. For the VLF bands, they are asking for suggestions. What’s the bandwidth? For the common bands, it sounds like 2.8 kHz is the answer. However, modern techniques often squeeze more into less and the FCC will finally recognize that by converting the limit to signal bandwidth, not baud rate. No one wants to have an entire band consumed by a 10 Gb RF network. However, the FCC currently limits the baud rate to 300 baud or less, ostensibly to restrict signal bandwidth. Besides that, cheap computer soundcards make it easier than ever and sophisticated digital modulation techniques have long left the old, clunky TeleType in the dust. Ham radio operators have long used digital modes like radio teletype and with restrictions on antennas and increasing interference from wireless networking to solar panels and more, digital has become even more popular than in the past. We’ll save you from grabbing the calculator. It appears the relaxed rules would apply only to some bands, notably some VHF and UHF bands along with the 630 meter and 2200 meter bands, which - we think - are lightly used so far. In particular, they want to remove certain baud rate restrictions that have been in place since 1980. The FCC is circulating a proposal for new rules pertaining to amateur radio in the United States.
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