Am broadcasting

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energy105
New registered user
New registered user
Posts: 13
Joined: Thu Jan 20, 2005 10:12 pm

Am broadcasting

Post by energy105 »

Hello there, I have installed many fm radio stations ranging from 1 watt to 4kw. I guess nowdays It don't need much to do that. A huge dummy load. a few antenna anylisers and the knowledge to put on a connector. But even at high power nowdays they make it so easy with technology. But myself a always had an Interest in Am Broadcasting. The thing is I know nothing at all about am since it was completely out of my time ( yea im a young one 20 years old :) ) And its not like there are people around into that from where i am. So I decided since the AM band is completely cleer that it may be to my advantage. (and it was) Didn't take much to get a 1 watt license to operate on am. Ok cool so now im all ready to go.
Problem is when I read up on the antenna I found out that it was more then just a wire. That on am well for my freq of 750khz id have to have an antenna of at lease 314 feet well around there from what I remember. So yea I could see the massive losses with just a few feet of wire and prob blow up the final stage of the transmitter. So i did some more reading up on this and found that they sell from a few places what they call those FCC no liencse antennas that meet this spec. Ok now thats cool. I can go buy an antenna but wait! this ant makes sure that its a certian lenth so it dont voilate the fcc rule by going to far. But for me in my little town the point is to get as good as I can. So id prob be defeting my goal to put one on these on my roof and only go 1/4 mile. So I did some more reading online and found out that you can match just about anything with a loaded coil. So I did more reading up on this. I will be honest I don't understand a thing they meen. They go from one spec to a wire lenth to a inductance and Just on paper expained fast like that. I can't even picture how id make one.

Ok so here is my plan so far. I live on a 1 story apt. I have a pritty big porch. It sits at about 20 feet from the ground. I would like to stand up a 22feet stainless steel pol on there and use that as my vertical antenna. feed my rf to that poll. and then pass the ground to my tower on the other end of the apt. I figured am needs a good ground and my tower is deep in the ground so id be able to easy attatch the ground to my tower.

ok so now somhow i need to make a loaded coil before the antenna. again this is where im stuck. I dont even know of a simple formula to just spit out the readings.

another option I looked at is a antenna tuner. I looked at these on ebay and they are mostly only for cd or that I have no clue if it would work on am. Some have more specs then others ( none say the actual band just specs) again I don't know what specs this would fall into to go look for the right meter. the closest I guess would be 160 meter ant tuner but thats still a few megs up and it might not work or will it?

now suppose all is setup right with what I got. again i have no clue on how range works on am. I know id prob get beat up at night with all the skip but in the daytime on a normal day with 22 feet of verticlal antenna well matched with one watt of carrier.. how far could I get. I'm hopping to get my whole town covered. about 2 miles in all directions. Could it go this far ..less far or even better more then that?

Could any body please give me advice .. do you think my setup will work. if you have any info at all as what im looking for please reply.
thanks :)
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