T-Rex 450 se V2 fpv build and set up

[aaronredbaron]

yeah, the anyvolt spews rf like crazy, make sure you use a filter if you use one!

[l14m]

I thought that was the case and so for safety I'm switching back to a two battery system. Flight pack being a 4s 2450 and fpv gear running from a 3s 460. This gives me about 8-9 mins flying time and about 45 mins fpv gear run time.
Liam

[gitcho]

this thread may have changed my mind about installing my first FPV system in my plane. My biggest concern is obviously losing my plane/heli, but I figured RVOSD5 with RTH (properly configured) would save my plane in the event of signal loss. I've got a Trex 550e + SK720 that I would much rather fpv with, but have 1.2ghz 1W vtx, and would likely lose RC before video .... sounds like <1.5 miles is the useable range people are flying on 2.4, but not sure how one *knows* you're about to lose RC control.

There's no fpv-heli-4-n00bs section, so I'll ask here: am I correct in understanding that most of you are judging your FPV range limits with the RSSI indicator? Is it also true that my spektrum Dx8 + AR7010 receiver cannot display RSSI with my RVOSD5?

[l14m]

Hi not sure about rvosd5 as haven't used it but a friend has it on his wing and has said it's great. There are a few ways to see if you are at the limit of your Rc range. Firstly and in my opinion the best is RSSI and the second is to put your camera on a pan or tilt and have it so if you get any glitches it will either centre or go to a preset position. Also I never had much luck with 2.4 or 35 for Rc control and so switched to a UHF long range system. It's very hard to get a heli well set up for fpv, the biggest problem is the Rc range as the video is a lot easy to get 1-2 miles. You shouldn't need more than 500mw for that distance and I'd say 1000mw is over kill. I used 1000mw for awhile and found it reduced Rc range because the electronic noise it omitted when close to other electronics (Rc tx).
One thing I would say though is although it's hard and takes time to get a good set up with a heli. The rewards are well worth the time.
Regards Liam

[gitcho]

yeah - saving the pennies for UHF. Was hoping to get a bit of short-range practice first with 2.4 for RC and 1.2 (on a diff channel) for vtx. If there's no way to get RSSI from my DX8 + AR7010, it's useless to me ...

[l14m]

I'm sure you will be ok for short range fpv but make sure you don't step outside about 400 m.

[l14m]

After setting my heli up for a two battery system and having every thing working! I went to a meet today and switched everything on only to find no picture. Vtx was working but some things either happened to the cam or osd. Back to the drawing board.
Liam

[l14m]

Right after drawing a quick schematic I found that switching from a single batt system to a 2 batt system left me without a ground from vtx (cam side) to the osd, thus the osd and cam wouldn't work. It's a lot easier to fault find on the bench at home, than the grass at a flying field lol.
Liam

[l14m]

Hi all work has been manic over the last couple of months but over the last few weeks I have been working on a new project.........

[ame]http://www.youtube.com/watch?v=LjNg8NwkdGE&list=UU2gz8-CBraw0APislx84tRA&index=1&feature=plcp[/ame]

Regards Liam

[Tomstoy2]

Nice! Where did you pick it up at?

[l14m]

Not picked up, hand made lol. The tracking is done with the ez tracker and the servos are from servocity. The base plate ect was hand made.
Regards Liam

[jeremy cooksey]

Originally Posted by l14m

Not picked up, hand made lol. The tracking is done with the ez tracker and the servos are from servocity. The base plate ect was hand made.
Regards Liam

You DA MAN!

[l14m]

Cheers, not really that hard to make just a lot of cutting and soldering of wires relays ect. Relays were needed to run the servos 8 amps and a mini one for the vrx. The vandle resistant switches are only rated at 50ma. I might even buy an fpvjapan dvr which has a small screen. I can plugmy goggles straight in the side of the tracker which makes it a self contained unit. Cost was approx £400 + , got hit with £59 customs charge.
Regards Liam

[l14m]

Went out to test my newly built antenna tracker at the weekend and found it would freeze after about 600 m. The reason for this is the lawmate tx audio sub carrier drifts to much and subsequently produces to much distortion for the ez tracker to read the data carried along the audio Chanel. Oh well more research and tinkering, the good news was I managed 3k easily with my wing but need some better weather before the heli goes up again. Once I get the tracker worker I'm going for 2.5 k and back and then 3k, should now be able to manage this distance quite easily with some fast forward flight.
Liam

[SENTRY 62]

did you try adjusting the audio pot? Have you performed the cooling mods?

[l14m]

Hi Sentry, yeh I've played about with the pot but its the lawmate audio sub carrier which drifts. I need to grab a favour from a friend who has an oscilloscope so I can either put the correct size resistor on the audio line or change the sub carrier in the tx. It's beyond my skills but my friends an electronics genius. I would have switched from lawmate gear and bought the new 2.4 duo but several of my friends who have the old version and bought the new one, arnt pleased with the results. So I will hold of switching brands and frequencies for the moment.
Liam

Also what cooling mods were you talking about ?

[SENTRY 62]

A lot of times the LM only drifts due to heat - that's why i was asking if there are cooling mods done to the vTx.

[l14m]

No but I have been In touch with Dpcav as they do in house calibrating and sort the audio issues out with Lawmate vtx's. $99 for 1.2 ghz 1000mw so may give it a go and see if it resolves the audio.
Liam

[SENTRY 62]

The 300mw units (seem to be actually about 400mw) are rock solid. And they don't get as hot as the 1w units - might be something to consider - especially since long-range is really not achievable on a heli.

Let me know how it works out.

Sentry : FPVLAB.COM

[l14m]

In all fairness the heli is running 500 mw 1.2 at the moment but I'm waiting for funds to swap the osd from Eagletree to ez so as to run the tracking on it. It's my wing that's running 1000mw and has the audio drift problem. I'm going to swap them over tomorrow and test to see if it works better and if the results are better then I will buy another 500 mw lawmate vtx.
Sanders has replied to a 1.3ghz thread over on fpvlab with some soon to be work arounds hopefully or even better he will hopefully add 1.2 to the immersion range.
Cheers Liam