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celeste

FPV 35MHZ range problem

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I'm looking from some advice how to improve transmitter range using 35mhz. At present I can confidently travel out 200m (reported by EZOSD OSD) at multiple location but roughly beyond this point I start seeing signs of a poor signal such as the pan camera glitching and delayed servo response.

Here's my setup

easystar_fpv_layout.jpg

Radio TX Futaba 7cap 35mhz

RX Corona RP8d1 ppm

Vid TX 10mw

RC plane Easystar with ailerons brushless

When I performed futaba's recommended ground test with aerial down and managed 60 feet. I get the same results using a futaba R138DP pcm receiver, also the same results when I only connect a single servo. Using different Futaba crystals or synthesized receiver also produces roughly 60ft test.

Is this the maximum distance I should expect from 35mhz, could the radio tx be faulty, perhaps local interference or possibly a combination of all three.

I would be grateful if someone could kindly share there setup and range they can comfortably fly out to without concern with using standard kit.

Recent vid showing EZOSD and RSSI percent falling as I near 200m.

http://www.youtube.com/watch?v=OdDnG7INnGY

Edited by celeste

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When I performed futaba's recommended ground test with aerial down and managed 60 feet.

It seems to me that something is wrong. The 60 Ft aerial down range is what I would expect from a low cost park fly'er receiver.

Comments:

(1) Do the ground range results improve when you test with ALL the video equipment turned off?

(2) Have your borrowed another Tx to see if it solves the problem?

(3) Your R/C antenna is routed directly under the video Tx. That could reduce range when the video Tx is operating.

(4) Post some clear photos of the installation. They may help someone identify ways to improve your range.

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I'd try removing/putting the OSD far away from the receiver. I've already seen strong interference from the MCU clock from another OSD in the past. Apparently your RX is OK if the 138DP gives similar results, so after that I'd suspect the TX is faulty.

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Thanks for the suggestions. I have a feeling it's radio TX related as the range check didn't improve when the video gear was switched off. With just a powered esc and servo and still only get a 60 feet check. The issue is I don't have a good range check to compare with for my location. Once I have a benchmark I can start adding the other devices and measure any lost.

I'm going to try another TX and I'll post the results.

Cheers,

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Thanks for the suggestions. I have a feeling it's radio TX related as the range check didn't improve when the video gear was switched off. With just a powered esc and servo and still only get a 60 feet check. The issue is I don't have a good range check to compare with for my location. Once I have a benchmark I can start adding the other devices and measure any lost.

I'm going to try another TX and I'll post the results.

Cheers,

Hello!

How did it go? Did you find out what the problem was?

I have the same problem on my plane now. Same corona reciever.

The strange thing is, that on my old plane I could fly nearly 5km with rssi showing 60% - 70%

But now in my new plane it is just like on your video. Just cant figure out whats wrong.

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