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CBU's 6160 khz SW relay not effective at all.
A 50 kw shortwave transmitter (running DRM, backward compatable AM + DRM modulation) and a Horizontal Log Periodic antenna could serve 50% (potentally 75%) of Canada's landmass. http://cbc.am/cbc.htm Canada's rural and northern populations are for the most part not fully served by AM & FM radio stations during daytime hours. Although CBC North runs an extensive AM / FM and TV network for northern Canadian residents -- there are still millions of square kilometres that the CBC-SRC will never be able to reach with its current broadcast network. The lack of daytime information radio network service does not help northern and rural residents in their day to day lives. It goes without saying that the lack of access to an information radio service in Canada's remote regions increases the demands on expensive to deliver federal and provincial services. Poor delivery of basic government services has led to a negative relationship between northern and rural residents and Canada's southern urban population. In a matter of speaking CBC-SRC has pretty much failed to meet fully the news and information needs of all northern and rural residents, since these residents fell into the revised CBC-SRC mandate in the 1970s. This mandate is providing a basic information radio service to all of Canada's regions. Most of Canada's populated remote areas can be reached cost effectively with two shortwave transmission sites. Shortwave is an ideal media for delivering radio programming to remote regions during morning, daytime and evening hours. The proposal before you is for a transmitter site in British Columbia that could serve western and northern Canada and a transmitter site in Newfoundland that can reach Labrador, Northern Quebec and regions in the high arctic that are poorly reached by the BC transmitter site. Technical Notes This proposal is for a two frequency network in the 49 meter & 41 meter bands shortwave (in the ITU band allocation system) using four fixed frequency 50 kw transmitters. It is possible that higher powered transmitters could be used to combat shortwave fading. Current calculations suggest that a slightly higher powered transmitter will be needed to reach listeners in eastern Canada, as there are more severe ionospheric distortions due to Quebec being situated over the magnetic North Pole. The two transmitters would be expected to run in parallel around 16 hours a day, out of a shortened 112 hour week transmission schedule. It is assumed that the shortwave transmitters would be fully DRM (Digital Radio Mondiale) compatible. DRM allows for FM radio quality digital audio over very long distances. DRM is fully backward compatible with existing consumer and professional shortwave receivers. I expect a new frequency allocation for this shortwave service, as the CBC-SRC is already using two shortwave frequencies (http://www.cbc.ca/frequency/shortwave.html). The CBC-SRC needs to make a uniform allocation of 40 khz for domestic shortwave broadcasting within the 49 m and 41 m bands. This allocation would be made for use by all domestic shortwave broadcasters. These area coverage computations do not represent full optimization. The frequency and antenna types may need to be altered to achieve the goal of covering 95% of Canada's land mass with a reliable shortwave service. |
#2
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![]() "http://CBC.am/" wrote in message ... CBU's 6160 khz SW relay not effective at all. A 50 kw shortwave transmitter (running DRM, backward compatable AM + DRM modulation) and a Horizontal Log Periodic antenna could serve 50% (potentally 75%) of Canada's landmass. As much as I used to enjoy shortwave listening, the times have changed. Much of the unserved land mass you mentioned is now covered by Canada's domestic satellite radio and TV services. You're worrying about one shortwave signal while rural families are snuggled in their homes tuning in CBC radio and TV, CTV and even TV Land. |
#3
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http://CBC.am/ wrote:
. DRM allows for FM radio quality digital audio over very long distances. Really? FM quality means a S/N ratio of at least 65dB and and no more than 1% peak distortion, most of it low harmonic. This requires even with the best digital codecs at least 96 kb/sec, and probably a bit more (for stereo, of course .... for mono the FM S/N level should be set at more like 75 dB.) What is the bandwidth of these digital signals that get 96 kb/sec? Doug McDonald |
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