Transponder Address...What is the difference between "H" and "V" in FTA

Hi Folks;

I'm wondering what "H" versus "V" designates in a FTA Transponder address....

Thanks in Advance,

Mike


H means Horizontal polarization while V means Vertical polarization.
 
I'm wondering what "H" versus "V" designates in a FTA Transponder address...

H means Horizontal polarization while V means Vertical polarization.

Can this affect my set-up or is there nothing to be concerned about?

Pmow,


Hi Mike, very glad to have you along here!

This item, the polarization of the signal, is very important to you.

Allow me to give you a very simple analogy about linear polarization (H vs V) or Horizontal vs Vertical.

Consider shooting a rifle with a scope at a target on a barn wall 500 yards away. You want to hit dead center in the middle of that "+". I am sure you have looked through a rifle scope before and seen the crosshairs in the site. One crosshair is vertically orientated up and down and the other is horizontally orientated side to side. If you twist or rotate your rifle, you will see how the crosshairs in the scope move into and out of alignment with the "+" target on the barn.

Next consider that the satellite transponder transmitting a signal uses two antennas, one set horizonatally and one set vertically. Then consider that the LNBF on your dish antenna to receive that satellite signal has two probes or receiving antennas, just like wires, with one set in a horizontal orientation and one set with a vertical orientation. Very much the same as the crosshairs in your rifle's scope.

In order to get the optimum signal strength from the transmitted satellite signal, you must align the crosshairs of your LNBF with the crosshairs (or the "+") of the satellite transponder's antenna.
This is called your "polarization" angle.

If the horizontal transponder signal has a frequency of "X" MHz and the vertical transponder signal has a frequency of "Y" MHz, then in your receiver menu, you must program this accordingly. If you reverse it, then your receiver will not identify either signal at all. Not just incorrectly, it absolutely won't see either in the remotest way. Because it will be looking for "Y" MHz on the horizontal transmission and "X" frequency on the vertical transmission, and both would be incorrect. So it is highly important to get the polarity correct.

Proper polarity is important, just like when jump starting your car. You wouldn't hook your jumper cables up incorrectly (+ to - and - to +). Of course, with satellite stuff, if you reverse the polarity accidentally, you won't cause any damage or blow something up, it just won't do anything. It just won't work and won't provide you with a signal.

Dish Network satellites (the majority of them if not 100%) use circular polarity. This is much different than linear polarity. Here, the signals are transmitted down from the satellite like a corkscrew. The signals are L and R or Left Hand and Right Hand polarized. So one signal corkscrews to the left and one to the right. The LNBF that you use for DN and circular satellite transmissions is much different than that for linear transmissions. The LNBF for circular signals would need to be like a funnel, but with a guide or channel like a threaded bolt hole. One threaded for right handed threading and the other for left handed threading.

It is pretty easy to visualize all these scenarios of polarization if you think of them in these terms. It doesn't explain how they accomplish it in tchnical terms, but we don't need to know that specific information just to use the technology. You just need to comprehend the difference.

I hope that my examples and analogies explain these differences sufficiently to paint a good mental picture so that you may understand the theory well enough to use it. If you want to get into the nitty gritty of engineering such things and how it truly is accomplished, then you better do a lot of research onyour own, because I cannot explain all this stuff in technical manners. :)

RADAR
 

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