Hi- I am VERY new, and I've been dying to find this forum. I mean, who can you really talk to? I belong to a couple of other forums, and when I talked about transmitting outside the legal limit, I got shot down. I'm getting ready to broadcast at 10 watts. I have a Free radio Berkley transmitter, stereo generator and filter. I have an extensive background both on the air and technical. I'm going to broadcast music, old radio shows, and local interest around my neighborhood. i don't expect to have any complaints because I'm 4mhz away from adjacent stations, and all of the radio and TV services in my area are digital. Any suggestions or comments? Terry
What kind of antenna you plan on using? With 10 watts and a good aerial on the FM broadcast band you can easily cover a small town of 5 miles radius or more. After all that's 1/3 the power of what most larger legal FM stations run. Maybe get a few of your friends to do shows on your station? BTW welcome to the forums. There are people on here but there is a lot of lurkers and people who only post replies if it's something they know how to reply on or interested in.
Ah, a live body. Yeah, I've been working on this for months. I had built a ground plane, but went ahead and bought one off of eBay. I have the 10 watt PPL from Stephen at Free Radio Berkley, plus the 7 band filter and stereo generator. There's a guy here in town that went to school with Stephen and builds linear amps for CB's. He has all of the equipment to tune the transmitter and antenna, and test everything for harmonics, distortion and stability. He's got my stuff and we're waiting for the new antenna. I'm pretty sure I'll be able to stay under the radar. I only need to cover a good square mile, so I might even back off the power. I live in one of those "Old Town" areas, Old Louisville, centered around a court and park. I'm a photographer and have a very cool dog, so I'm pretty well known in the area. There are a lot of people who want to be involved. There'll be local shows, old time radio programs, original music-stuff like that. I was a local radio personality for several years, so the station will be very professional. The good thing is that it's harder to cause interference since everything, including emergency channels, are digital. Without an interference complaint, who's going to know, right? Terry (non compos mentis)
Okay- if anybody's paying attention- I got a new ground plane off of eBay and I've dropped everthing off at Stephen Dunifer's old snip buddy name. He has a shop here in town. He's going to play with everything-the 10 watt transmitter, stereo generator and 7 band filter to make sure it all works. Hopefully I'll be picking up a working radio station next week. I'm SO EXCITED!! More later. T
20 miles with a jpole and 700mw?!?!? you live on a mountain?
i built a copper jpole and got it tuned flat for my fm freq. ran a 5 watt hlli and got a solid 2 miles. i live in one of the flat states. theres more pirates than you can shake a stick at here though. my freq was reasonably clear.
must be band pollution here then. i tuned my antenna using an mfj antenna analyzer with the antenna mounted on a 3 foot test mast on open land. i know that was working right. my coax is less than 40ft of 9913.
Post by HighMountainRadio on Jan 12, 2018 15:51:58 GMT -6
Welcome Terry ! Glad to hear that free radio is alive and well in that part of the country ! Good antennas are quite easy to build for CHEAP ! There is a local scrapyard near me where I shop for all of my aluminum tubing which is quite prolific at this particular scrapyard so basically it can be purchased for the sake of the cost of scrap aluminum ! It may pay you to explore salvage yards in your area as well ! I build and have built all of my antennas and they work terrific ! One thing you didn't mention is using a 'balun' at the antenna feed point to keep the coaxial cable from radiating and causing high VSWR (Reflected Power) back to your transmitter. I HIGHLY recommend making and using one ! With 10 watts output here I was getting 3 watts reflected power, NOT a good thing at all ! In order to make a balun all you have to do is use a length of whatever coaxial cable you are using (9913) and wind 6 turns into a 6 inch circumference keeping each turn next to the previous loop (you DON'T want 'scramble' windings) Keep it all nice and tidy. You may utilize small pieces of wood furring strips to keep the turns of cable uniformly adjacent to one another. Then use simple electrical tape to hold it all together. Use the wood furring strips on both top and bottom of windings secured by wood furring strips or something similar (plexiglas), etc.. Use whatever connectors are proper for your 9913 cable, One connector goes to the antenna feedpoint and the other end goes to your feedline. RF adapters will be required unless you simply wind the balun at the end of your feedline, thus incorporating it into the feedline itself, an integral part in the feedline.. That will keep your coaxial cable from radiating along it's length and will give you a nice flat VSWR if you tune the antenna to proper length for your intended transmitting frequency. This is a VERY important part and not to be sacrificed ! It will keep your transmitter final output MOSFET or transistor very happy and maximize your power to the antenna feedpoint where you want it and not wasting it along the length of your feedline.. Keep us posted on your progress ! I am pretty new here myself and really enjoy being part of the group, it's a great bunch of like minded individuals !
Best regards, Spooky... (High Mountain Radio) - "Broadcasting From Somewhere High In The Remote Appalachian Mountains"
"Knowledge Is Always Made More Valuable By Sharing It With Others !" Always Remember To Be Kind ! True Greatness Often Has Very Humble Beginnings ! Help A Kid Out Today ! *** High Mountain Radio *** "Broadcasting From Somewhere High In The Remote Appalachian Mountains"
Post by "Skidmark" Fred Douglas on Aug 6, 2018 16:51:57 GMT -6
I'm new to all this too. Since it's not cool to name drop, fine by me, and being that I'm not really on Tulagi I'd be interested to get your opinions on additions, boosters, ETC. The FCC has been spazing out on the scalawags down in my neck of the woods.
I'm actually thinking about going mobile as my "small RF maker" is PLL. Antenna is really the problem I'm having. Funny thing is I get the vertical dipole ETC, but "on the fly" I'd like to know what your thoughts might be.
I'm very new here but thought I would jump right in and ask some questions.
Thanks for reading and I guess this is the paddles to the chest on this thread.
I'm new to all this too. Since it's not cool to name drop, fine by me, and being that I'm not really on Tulagi I'd be interested to get your opinions on additions, boosters, ETC. The FCC has been spazing out on the scalawags down in my neck of the woods.
I'm actually thinking about going mobile as my "small RF maker" is PLL. Antenna is really the problem I'm having. Funny thing is I get the vertical dipole ETC, but "on the fly" I'd like to know what your thoughts might be.
I'm very new here but thought I would jump right in and ask some questions.
Thanks for reading and I guess this is the paddles to the chest on this thread.
I don't know about mobile dipoles. I don't think they exist. There are mag-mount type antennas that will stick on the top of your vehicle. They even make some specifically for FM broadcasting. You should be able to find them on ebay. I think the name of the company is fmuser. The top of the car acts as the groundplane I think, so the radiation will be similar to a ground plane antenna. If you can't find one for broadcasting, you could always buy a ham one (6 meter band) would be optimal because it's a little longer. Then you can just cut it to the correct length for FM.
If you're talking about non-vehicle mobile, then you might get a pair of rabbit ears (the telescoping antennas that used to be on TVs). They are basically a retracting dipole with adjustable length. Just record the length you need to extend them to with an SWR meter and then you can easily deploy them at the right length. Might not handle too much power, but should be fine for a watt or so. You may also want to replace the coax with some 50 ohm instead of the 75 they come with. Not sure how well a 50 ohm TX will work at 75 ohm. Never experienced that.
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