TV-Transmitting Antenna 490MHz

[bravodenisu]

Good day friends!
I have in the village a small TV-sender (analog) half a watt of power running at 490MHz. More than 3 years I transmit a picture of my camera showing how the weather is outside, and some music in the background all OK but I have a range of only 400 meters. I would at least 800-900 meters! I want to make a better antenna, however, because of all that I tried some of them probably did not made exactly the best that I knew ... - - So I asked you if you want to help me to understand because, after all, about antennas, signals ... but to me it is a wish already long but just can not make it ... I do not know the precise dimensions of 490MHz.

A little problem is that my house is in the middle of the village should send a signal (in all directions OMNI) Horizontal polarization because all the TV antennas are horizontal.:'(
http://prntscr.com/aqte6s
If you can vertical polarization, made to a GP (Ground Plane) or J-Pole ... but you probably can not. Changing the polarity is losing a lot!
- Which dish do best?

From TV-sender to Antenna 5 meters by cable (H1000) 50ohm!
http://prntscr.com/aqtsg4
- Is this good? Dipoles turn 90 degrees, or what do you think, maybe another dish to do to be a good and precise at 490MHz ???
http://prntscr.com/aqttdy

THANK YOU !

 

[Red Squirrel]

From my understanding the watt to distance ratio is logarithmic. So if you raise to 1 watt instead of 1/2 watt it will increase range a bit but not double it. I'm not familiar enough with all the calculations involved but my guess is you'd want to maybe transmit at like 5w or so. You can also look at more directional antennas and have multiple sectors. This would mean you can shoot the waves further as less energy is used to shoot in directions you don't need like the sky.

 

[bravodenisu]

The power of 0.6 Watts maximum power is mine. Stronger can not because it's A-Class for video signals. That's why I do not want a big range. I want to just 800-900 meters or (900yd).
Thank you!

 

[Born2bwire]

If you want an omnidirectional transmission there isn't much you can do. Any antenna you find is only going to give you better range by directing the signal. Instead, I would make sure you have matched impedances and a proper balun (if needed) to maximize the power delivered by your source. If you have been using a horizontal antenna, then are you ok with directed transmission? You would have had to point the null at somebody I would think.

 

[bravodenisu]

I do not understand completely because of the translation ...
I do not know if I would have been completely right this antenna, or not?
http://prntscr.com/aqttdy something should be changed?
- Or if we propose another antenna that worked correctly in the 490MHz Horizontal.
- Or maybe 2 antenna somehow to cover almost the entire circle?
I want to thank you for help!

 

[AD5MB]

there is one kind of omnidirectional horizontal antenna: the turnstile array. two dipoles with a 90 degree phasing harness

there are a few vertical omnidirectional antennas with gain. the one that might be useful for you would be a collinear array

four collinear arrays arranged as two dipoles, 90 degrees apart, may function as a turnstile with omnidirectional gain.

find an amateur radio operator to help you design, build and test this thing.

 

[bravodenisu]

there is one kind of omnidirectional horizontal antenna: the turnstile array. two dipoles with a 90 degree phasing harness

there are a few vertical omnidirectional antennas with gain. the one that might be useful for you would be a collinear array

four collinear arrays arranged as two dipoles, 90 degrees apart, may function as a turnstile with omnidirectional gain.

find an amateur radio operator to help you design, build and test this thing.

-------------------
Only if you have some pictures or ... to see how it looks.
If I could do it slowly to 490MHz Horizontal!