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Post by Boomer on Jul 27, 2019 3:09:11 GMT
By Jan Lipski ".. AM radio is still a viable method off reaching out to a broad area of the country. Night-time the listening range can extend to several surrounding states. These stations, especially the 50 kW operators provide continuous signals while driving long distances. In times of an emergency like widespread power outages they could be the only information source available." "I don’t think AM radio should go away. I think the local low-wattage operators should fold up shop. They don’t appear to be good stewards of broadcasting. Many times they are off the air or they have a carrier but no modulation for hours at a time. " More: www.radioworld.com/columns-and-views/readers-forum/letters-am-doesnt-have-to-go-away
For me, I'd like to see some improvement in Part-15 rules, to liberalize them more, and also to have an LPAM service established, enough power to cover your small town, with a simple antenna and ground requirement, but not so much power that it would skip and interfere with other stations at night. Make EAS and all other requirements simple for the few people who will tune in. Boomer |
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Post by thelegacy on Jul 27, 2019 4:10:23 GMT
The IT WONT HAPPEN club continues to stop that from happening. Just when I thought there was some light the end of the tunnel, Michelle Bradley started singing the ever proverbial song we've been hearing for the past few years of any attempt for more power.
She started talking about how the statement could hurt her attempts at lpam or LPFM changes in the future.
If ever there is an LPAM service you can best bet from what I hear from Michelle it'll be just like LPFM which will be so limiting that it makes it impossible for an individual to set up their own radio station and that is not what we want.
Instead there should be a slight increase of power for the hobbyist maybe somewhere between 1 watt and possibly 10 watts I don't see why V Watts whatever be a problem just enough power to cover a 2-mile radius to a decent car radio or a very high-end home radio.
The problem with AM radio is the crappy radio available in the United States and I don't think you're ever going to get millennials to really think about listening to a.m. . Now back in the 70s you might had got a few teenagers to listen it would take quite a bit of non-commercial programming but I'm afraid these days the millennials don't care about anything other than the same old dirge of top 40 rap and maybe this young country stuff which is a mixture of country and rap mix. To me I think AM should be more geared towards the older folks who are open minded and already understand that there might be some static once in awhile but with good programming they will listen anyway knowing the limitations of AM radio with a good radio.
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Rich
Full Member
RF Systems Engr (retired)
Posts: 112
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Post by Rich on Jul 27, 2019 10:26:12 GMT
... I'd like to see some improvement in Part-15 rules, to liberalize them more, and also to have an LPAM service established, enough power to cover your small town, with a simple antenna and ground requirement, but not so much power that it would skip and interfere with other stations at night. ... No matter what their radiated power, AM broadcast stations use vertically-polarized transmit antenna systems. The reason: for other things equal, horizontally-polarized transmit antennas produce much lower groundwave field intensities at/near the surface of the earth around the transmit site.
But the radiation patterns of both horizontally and vertically polarized transmit antennas have significant fields at higher vertical angles above the earth. Those fields can reflect from the ionosphere and return to the earth many miles from the transmit site, which can produce interference to other stations using that frequency.
Unfortunately, there is no way available under the laws of Physics for a vertically-polarized transmit antenna configuration that will not produce a very significant amount of high-angle (skywave) radiation.
Increasing the power radiated by vertically-polarized transmit antennas will improve their skywave fields to the same degree it improves their groundwave fields.
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Post by Boomer on Aug 8, 2019 23:03:09 GMT
When an idea gets some popularity, people will always try to claim it and add their politics. We all do it. Now if Michelle Bradley was part of LPFM, I wouldn't be surprised if she wanted a similar structure for LPAM, going with a model that worked, and with the level of regulation that the NAB and FCC would be comfortable with.
I wrote this to a friend about the long distance Traveler's Service station I got at 150 miles, and why AM might be useful to some community broadcasters.
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That was great reception, those transmitter antennas are on simple poles by
the side of the highway, and the output power is under a watt, going by my
calculations it could be 1/4 of a watt. That shows what can be done with low
power to get 150 miles.
SDR's are digital tuners that people run, and you can tune in by a browser
over the net. It's like a full featured radio right in front of you, all of
the AM bands from longwave to shortwave, that can be heard where the
receiver is located.
There are actually advocates in Part-15 radio who want to use rules based on
TIS to make LPAM available, as there's low power FM. We already have that
model that works, TIS has a local signal for about a mile, and there's been
no known case that can be found of a TIS station interfering with a
commercial broadcast.
Contrast it with FM, the FM band in many areas is getting full or is filled
up in cities already, yet there's still a need for broadcasting space, so
people are saying, why not open up LPAM? It might not be seen to be as good
as FM, but it could fill a community radio need for some, and the local
range of the signal would be about a mile where it's strong.
It's even better as far as transmitter sites are concerned, no expensive
tower rental is needed, it can be a pole in a city lot, or even a 1-story
building roof.
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Boomer
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