i still would like to get a good signal am and / or fm up at the pool in our complex which is about 250-300ft away from me. my main transmitters are a Waio BR8000 certified part 15 fm transmitter and a procaster for am.
i have another procaster, some surplus UPS with good batteries i can scrounge, i am sure i have a PLL fm portable somewhere.
i am thinking a fm yagi wired to a fm portable to pick up off the air my part 15 fm and feed that into the procaster and put it all in a weatherproof enclosure with a solar panel on a mast close to the pool area.
it will be conpletely self contained and self sufficient and not reliant on anyones internet or elctric.
it would be nice if i could obtain permission from the complex manager to install it out of the way somewhere close to the pool or find a resident on a second floor close to the pool who would let me munt it on their porch.
just an idea i have been playing with. i still need to find a lockable weatherproof enclosure and a solar panel of sufficient size and a charge controller likely find both cheap at harbor frieght and to either buy or build a fm yagi.
what do you guys think? i think a good sensitive dc powered portable connected to a yagi pointed in the direction of my part 15 fm should make it 300ft even with some obstructions.
You can build a 3 element beam antenna for FM by cutting some aluminum stock and using a fiber glass doll with screw in holes for the middle piece of stock you need to cut in half for the middle radiating element. I think the boom is 16 inches long its been so long when I got the formula from N8DEF when I lived in Michigan. So the middle element has to be 4 feet 9 inches and cut in two. You'll need to cut two holes in it and make them so you can screw in the 75 ohm coax. You could even use this as an FM antenna to transmit your signal too. Now you need to use a lathe and make the pieces so they can be screwed into the fiberglass doll which you'll use as an insulator so the two halves don't actually touch the boom. This is where inductance once again comes into play for transmitting and or receiving. You'll also need to have two holes in the middle of the fiberglass insulator so you can screw the two halves of the boom into it. The 16 inch rod used as a boom has to be cut and made to screw into the insulator. Now at the ends of the boom you'll have a 4 foot 9 inch rod and a 4 foot 6 rod which in the middle will have a hole in them to screw on to the ends of the boom. Now you have a home made FM antenna. I used this a long time ago and when I transmitted from that antenna I got 3 miles and that was under a watt and before I really knew about part 15. For receiving I could pull in WIQB Ann Arbor from the west side of Lansing on Grand River and Francise Road. Ann Arbor was 1 and a half hours from me and there was a Jesus Christ station broadcasting in Grand Rapids which was to my west I had to block to get the Album Rock station in Ann Arbor. Since my house was so close to the airport I didn't want my signal to transmit towards Lansing, but rather I wanted to transmit towards Grand Ledge High School. With that beam I was able to get the job done. Now I'm not saying your transmitter will get 3 miles for part 15 FM today (if we get the rules changed and that field strength at 250 uVm at 90 meters we'd make a mile maybe two Legally). Your receiver would have a better chance of receiving your part 15 FM signal because of the gain of the beam. I'd get a Yamaha Stereo or a good Digital FM tuner. You could even buy a CB power supply and find a junk oldsmobile car and take out the Stereo. Now put the car speakers in a wood case and you have a damn good FM receiver. My uncle done this because he was sick of the crap in house Radio's today. Hell it may work good for AM too. Just use a good AM transmitter. But if you want to have good FM that is what you can do. A Tecsun Radio like the 310 would probably receive AM and FM quite far as it is. Just hook that to an amplifier. We'll see how far I can get my talking house AM transmitter to go when my room mate moves out of the room upstairs. I'll just get an AV transmitter and I'll be able to transmit my signal upstairs. Maybe even use my phone to stream to the AM transmitter and from there its home free to send to the masses. I have a 10 foot window and that is all it will take man. Can't wait to try this.
Hi Robert. Your project description skips over certain details, so I have a question or two.
Once the pool area is blanketed with a good AM signal, how many people hang out at the pool and will they have portable radios?
If people bring radios to the pool will they all want to hear the same station?
Maybe some of the people will switch to FM, that could be a problem.
What programming will you be putting out there?
Technically the idea seems solid.
Did I read that right? The pool area is 300 feet away and you're not getting a good AM signal there with a Procaster? Somthings not right there!
As for the idea of using a yagi as an FM transmitting antenna -- technically sound, but probably illegal. If you focus the output of a legal Part 15 transmitter odds are that the field strength in that focused signal will be over the legal limit.
Tim in Bovey
i live in a first floor apartment opposite side of building from the pool within a major metro area. the building have some sort of chicken wire reinforced siding on the buildings in cobination with brick. my procaster is mounted horizontal on porch with no ground since it's 8ft off the ground. my waio fm does better than the am does. wasn't going to put the yagi on the transmitter was going to put it on the translators reciever to dig out the part 15 fm signal. to a very good all band portable the part 15 fm makes it to the pool if the radio is positioned right and in the right spot. so i want to stick either another part 15 fm and / or am right out at the pool to put a good strong signal over pool and office where the excercise room is.
Now, THAT makes sense! I believe TheLegacy mentioned using a yagi to transmit, which of course technically you could, but legally I doubt.
I was using a loop antenna at city hall (about half a block + a street width away) to get my AM signal to the office when I first started. I have my audio on the cable TV system on the public access channel and it came in there rock solid during the day on AM, but at night too much interference -- a loop antenna pretty much solved the problem. Since then the cable company set me up with a computer in the studio (some sort of rack mount computing device) that streams my audio right to them and into the channel, so no longer a concern.
Tim in Bovey
Man if cable FM still existed I'd be in luck because I could have had my station on Cable FM like they use to allow some hobby broadcasters to do back in the day on some cahle systems. As for as the beam antenna you can also use the same antenna build for just receiving if you want. I just pointed out that a long time ago when I had my FM station in Michigan that was what I did. Too bad you can't use AM where you are to achieve a good signal to a mile or two. I've heard so much about how under the right conditions a part 15 AM transmitter can get 2 to 3 miles. Here is a link to have some fun with although I am sure you won't put your antenna up quite that high:
Gotta Love AM Stereo!!!
if the managers allowed me to put the am up on the roof i would probably cover most of the complex and definitely the pool with a good signal from a single location, but it's not a private landlord it's corporate owned and anything that doesn't fit their little box the lawyers drew up for them isn't allowed.
You say you have no ground and the procaster is mounted horizontal?
The procaster works on 12 volts?.....using a computer(brick) style power supply(12V) with 3 PRONG....not just two, with power cord 3 PRONG will give you earth ground through the power cord. Also vertical is better...if horizontal there are dead spots where no signal gets out from the ends of the antenna. Even a 45 degree angle is better than horizontal.
Howdy kc8gpd & Others: Just so you know i own 22 am transmitters and have done various test on each units.
This is what i can tell you from my stand point.
I own a procaster tx and i can tell you when i did the set up test i did it in a vertical and horizontal position to get results.
Place in a vertical position.
DO NOT PUT IN HORIZONAL OR ANGLE in any shape of form your range will be very poor !
My drive test in truck & also a pocket radio comfirmed that the vertical antenna did better for range.
Also make sure your antenna is not near any metal objects so it dosen't detune and it will also cause range issue as well.
But you can have metal object below transmitter at a distance away and it will help reflect your signal to give you some range.
If part 15 am transmitter is installed right you will get out farther then part 15 fm.
Hope this help
station 8
unfortunately i rent and have to keep the antennas somewhat hidden from view due to lease restrictions
just scrapped the computer ups stuff i had, looked like i got 3x 12V 7.0A/hr batteries that looked in good shape, have to stick a charge on them and see how long they last, see if they are still good, there were 4x 12V 17A/hr's that didn't look good at all (cracked casing) sucks that they werent in good shape. two of those would certainly be plenty to run a remote site but i suspect the 3 7.0 a/hr ones should be just as good provided all 3 are good.
remember i need plenty of backup for days that we get no sunlight in additon to the night times.
Maybe you could try newer battery tech like Nimh or lithium cells as used in laptops and electric cars. Smaller and more power than lead batteries. That's a good idea for a remote AM station, rather than running wires for power. Maybe you could use a wifi link, or look up FPV on Ebay for transmitters and receivers.