Home made FM Antenna..
- Thread starter Valvetype
- Start date
kf8xo
Puts back the magic smoke
I cheated, but it was just a stellar day to get up on the roof yesterday ...
Most awesome skywire, this is my plan. Feed it into a coax switch...can't be beat.
sKiZo
Hates received: 92644 43.20°N 85.50°W
Long as it's not a Yoda Log ...
There is no try, there is DOO!
That's actually an FM-6 and a Magnum ST2 stacked. No switching - they're both ganged into the same feed down to the system. One vertical, one horizontal, so if anything, the receiver sees any crosstalk as just another reflection to deal with.
The yagidoo thingie is to get my favorite 3kW HD Radio college station from around 30 air miles. The ST2 could just barely see the station and cut out a lot, and fuggedabout the HD feeds, so that's where the yagadagadoo is handy, pointing right at the station tower. The ST2 is in a class by itself for FM DX otherwise. Playing around with it, I can get crystal clear analog stereo from up to around 130 air miles long as there's no local competition. And that's at only 20 feet height. Just chock full of awesome!
Hardest part was figuring out where to put the dang thing ... getting kinda crowded up there!
There is no try, there is DOO!
That's actually an FM-6 and a Magnum ST2 stacked. No switching - they're both ganged into the same feed down to the system. One vertical, one horizontal, so if anything, the receiver sees any crosstalk as just another reflection to deal with.
The yagidoo thingie is to get my favorite 3kW HD Radio college station from around 30 air miles. The ST2 could just barely see the station and cut out a lot, and fuggedabout the HD feeds, so that's where the yagadagadoo is handy, pointing right at the station tower. The ST2 is in a class by itself for FM DX otherwise. Playing around with it, I can get crystal clear analog stereo from up to around 130 air miles long as there's no local competition. And that's at only 20 feet height. Just chock full of awesome!
Hardest part was figuring out where to put the dang thing ... getting kinda crowded up there!
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c.coyle
Fighting the Dunning-Kruger effect.
Not when employing a vertical parasitic, inductively coupled, collinear decoupling stub, as shown in the photo.
loopstick
Lunatic Member
So what you're going for is an omni-directional pattern with some extra grab in the direction of the college station. And once this combo is aimed you tighten it up and you're good to go. Is that right?
sKiZo
Hates received: 92644 43.20°N 85.50°W
Yup ...
Got lucky the first time too. I maybe could get better, but I could also get worse, so I locked it down where it is and plan to leave well enough alone.
Also got lucky that none of the other antennas in the farm were in line with the college station's transmitter tower. I imagine that could have screwed things up some.
Something else you can play with is orientation if there's still signal problems. The ST2 can also be mounted horizontal - any angle really - and you can always tip the FM-6 a bit. Once again, didn't have to play that game here as it works fine as is.
Got lucky the first time too. I maybe could get better, but I could also get worse, so I locked it down where it is and plan to leave well enough alone.
Also got lucky that none of the other antennas in the farm were in line with the college station's transmitter tower. I imagine that could have screwed things up some.
Something else you can play with is orientation if there's still signal problems. The ST2 can also be mounted horizontal - any angle really - and you can always tip the FM-6 a bit. Once again, didn't have to play that game here as it works fine as is.
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sKiZo,
Where is the rotor for your FM-6? Do all the stations you listen too, come from the same direction?
I have an old deep fringe LPA, with a amp in the head. twin lead 300 ohm cable, it works really well.
Br1ck,
I use a Si4735 receiver chip, it has the ability to reduce FM noise considerably, since it is DSP based.
Anyone else use a Si4735 or Si4770 part?
Where is the rotor for your FM-6? Do all the stations you listen too, come from the same direction?
I have an old deep fringe LPA, with a amp in the head. twin lead 300 ohm cable, it works really well.
Br1ck,
I use a Si4735 receiver chip, it has the ability to reduce FM noise considerably, since it is DSP based.
Anyone else use a Si4735 or Si4770 part?
sKiZo
Hates received: 92644 43.20°N 85.50°W
No rotor ... just having a little fun - the one I pictured is for another project. I listen to stations all around me, but the one I really really wanted to hear is SW of here. I'm also getting a bit of a boost from some stations due south of here that were noisy due to a major metro area between me and them. The yagi yagi has a wide enough footprint that it helped those out considerably. Be interesting to see how it works come summer and heat haze season.
All other directions, the ST2 is killer all by itself. Same stations I was getting are still there, and just as strong.
Not to forget, I'm also using a signal amplifier - my trusty old Magnum FM85 ... VERY selective, which helps a LOT.
A pre-selector, "power sleuth" so you need to tune that device as well?
Imagine that, tune the antenna direction, tune the pre-selector, tune receiver to channel, all done manually, so much for seek/tune or remote operations.
I have reversed engineered the Channel Master rotor controller and working on incorporating the antenna rotor controller into my home brew radio. Know of any radios having this rotor controller feature?
Imagine that, tune the antenna direction, tune the pre-selector, tune receiver to channel, all done manually, so much for seek/tune or remote operations.
I have reversed engineered the Channel Master rotor controller and working on incorporating the antenna rotor controller into my home brew radio. Know of any radios having this rotor controller feature?