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Just got into FPV.

For xmass I got a Spektrum Fat Shark Micro FPV system.

https://www.spektrumrc.com/Products/Default.aspx?ProdId=SPMVS1100

The TX is like 10mW. Uses clover style antennas. I put it on a small heli and can fly out about 200ft. Past that and the video gets patchy.

So I'm thinking about getting a more powerful TX and camera that will give me a range of no more than 600ft. No interest in losing the model.

I might want to fly behind a small tree every once in a while :) .

How powerful of a TX should I get? Alot of guys use a 600mW TX.Is that necessary?

I do realize that I can use a helical style antenna to extend the range but those need to be pointed in the direction of the model.

I like to stand and keep my head still so looking to use a clover style antenna.

Thanks in advance Mike

HI TOM!

post-2682-0-01218800-1420053794_thumb.jp

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Hey Mike, it's fantastic to see you join the FPV revolution. Given what you posted, there's a variety of solutions to consider. But none as slam dunk as you might have imagined.

Your small heli needs a micro sized vTx/camera module like you are currently using. Unfortunately I can't think of any FatShark compatible alternates that have more RF power and the same small size.

Just for reference, your vTx is an FCC approved version that provides less than 2 mW's. That's not a lot, but with an upgraded vRx antenna (I suggest a 7dBi helical) it would be able to achieve 600 feet line-of-sight. The helical is directional, but aim can be somewhat sloppy and still work fine (just point it in the general direction you intend to fly). This is an example: http://www.dpcav.com/xcart/5.8GHz-Circular-Polarized-Helical-Antenna-7dBic-3-Turn.html. You're not too far from me, so if you want to borrow mine for an afternoon then let me know. This would give you a chance to see if a helical is a practical solution for you.

If you want to continue using your CP omni vRx antenna and instead move to higher RF power (200mW would be my recommendation) then the vTx will be much larger. Plus you'll need a separate camera. Do you have a larger e-heli in your fleet to handle the new/bigger components?

BTW, let's see a clear closeup photo of how you mounted the vTx antenna on your heli. It's like the age-old real estate mantra, where the three most important things are location, location, location.

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Yah I think FPV is awesome. Regular heli flying was getting a little stale.

Attached a pic of my current setup. The heli is about as big as a trex 250.

Since the cam is in the front of the heli I wonder how much of the signal is blocked when it is flying

away from me?

So the 3 coil Helical signal beam is pretty broad?

I might buy one to try with this micro spektrum setup.

I want to build a 250 Quad Racer and was not sure how powerful of a TX I should get.

I guess I could get by with a 200mW.

Or I could put this setup on a 450 heli that I have. But a quad racer might be more fun and more crash resistant.

post-2682-0-38255200-1420064217_thumb.jp

Edited by maarset

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Since the cam is in the front of the heli I wonder how much of the signal is blocked when it is flying

away from me?

When tail-in, the model has a significant RF shadow. Expect ~100% signal loss. With your installation location I expect other similar orientations and high altitudes will also experience RF attenuation (signal reduction) from shadowing. Ideally you would install the Cloverleaf antenna under the heli (vertical mount, pointed towards the ground). But your camera is attached to the antenna, so that means your image will be upside down. If you go with a separate vTx / camera system then you can do this sort of thing.

I want to build a 250 Quad Racer and was not sure how powerful of a TX I should get.

I guess I could get by with a 200mW.

From your posted info I agree you can get by with about 200mW; Fatshark offers a 250mW that will work with your goggles. But if you plan to fly behind sparse trees then ImmersionRC's 5G8 600mW would be something to consider.

Or I could put this setup on a 450 heli that I have. But a quad racer might be more fun and more crash resistant.

250 quad racer. Cheap crashes, Priceless fun.

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