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Old Apr 12, 2011, 05:36 PM
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You can use CL + Helical thou right with the LM vrx right?
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Old Apr 15, 2011, 05:43 AM
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Joined Sep 2010
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Is this: http://www.securitycamera2000.com/pr...5CH-700MW.html

the same as this: http://www.dinodirect.com/1-2ghz-700...R.html?cur=USD


What about the losses frequency lock at 8,75V, if I would power the vtx with a 3S lipo, that would mean 2,9V per cell, which would mean the lipo is already discharged, so this info is not a problem right? Regarding duration of flight.
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Old Apr 15, 2011, 01:59 PM
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NORWAY
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Quote:
Originally Posted by iacei View Post
LAST UPDATE: 13 04 2011

Latest News:

- Again: New jitter free servo found! And cheaper then the previous new one, Made the Test myself, not a single glitch (only if you make the antenna touch the metal tip of the gears)


DISCLAIMER: FOR US CITIZENS PLEASE REMEMBER THAT THE ONLY LEGAL CHANNEL FOR THIS SORT OF ACTIVITY IN USA IS 1280 Mhz

For Those who don't want to read it all:

Regarding the analysis the RC community made, the current suggestion of the chef is: Fox-800 (see 2nd Post) or the 1 W Lawmate if you want the best available and if you have 120USD to spend.

Here a small chart to help you choose:




Chart containing the available frequencies

For a small aircraft you can choose the lawmate 500mW too but beware, it is fragile, expensive and does NOT have 1280Mhz.

Alternative: use the small Tx from readymaderc.

GENERAL INFOS

Antennas

Stock Antennas give good results but here are some better ones

Tx: Go for IBcrazy's inverted Vee, better results and lighter



Even Better: Skew-Planar Wheel circular polarized omni antenna



or Cloverleaf (apparenty the best for omnidirectionnal)



But Wayyyyy more complicated to DIY and not compatible with the lawmate Rx!!!!



Rx:
- Goof Proof Antenna from RC CAM or IBCrazy's FAST Patch

- DIY Bi-Quad Best One for an Antenna Tracker.
- Moxon Rectangle or other Yagi (Easier to build - Cheapest)

- The Helical Antenna, IBCrazy's favorite





- For long Range Buy 1.2Ghz Yagi 21USD Do not Forget pigtail 5.5USD. Results: 17km on 1280Mhz


- Buy 1.2Ghz Patch (Expensive 45USD i.sh. - tuned for 1160Mhz you have to open it and trim the small plate to tune it to higher frequencies)



For Example: My Bob Tx/Rx was giving me 600m usable Video Stock and 1.4km with a Vee and a Homemade Fast Patch. Now my RC link is the weak link.

Servos

Some Servos do jitter a lot near a 1.2Ghz Vtx , the more you get close to 900Mhz the more you can have this Problem.

Here an example: 1080Mhz + HXT900

http://www.vimeo.com/19322275

Solutions:

- Try ferrite Cores and braided wires on your servos.
- Change frequency to go near 1.3Ghz (does not work with the HXT 900)
- Change your servos to one of these (If you do not agree please give feedback):

NEW: D933MG from HK
NEW: Cheaper just tested and still Metal Geared!: DS-929MG
Esky EK2-0508
HS-5085MG
HS45, HS56, HS65MG, HS82 + all the Hyperion Atlas models
The EMAX servos @ 1280Mhz.
hs -5065mg and 5485hb's

Avoid those:

9g blue ones do (rctimer, hextronic, turnigy, towerpro), Hitec HS82MG (Metal Gear), TPro MG90s and MG16R

General Tips / Tricks:

- Remove heatsink and place the Tx in the airflow on your plane, you won't need extra heatsink (not True for the lawmate).
- If your new Rx antenna needs an SMA connector you have 2 solutions:

Add an SMA port
Buy an F to Sma Adapter

- You accidentely crossed-over + and - and the Tx fried? Here one solution

- Would a Lawmate Rx perform better with this Tx? Not so sure, I did not see any big difference and this thread confirms it too. But more testing would be appreciated,

- If you are using only one battery and/or having interferences use this LC Sander DIY filter

or

12 V Regulator

Here

Watch out for RFI though, but it's a good tool for most of the Tx who loose power with voltage drop (NOT the lawmate)



FOX-700 aka the BOB Tx

One of the most popular in the 1.2Ghz FPV Community



Price (incl. ship.): 57.9USD
Buy
Manual (watch out some infos are wrong see beyond)
Real Tx configuration:


PCB pictures

Hints:
- has 1280Mhz (legal for the US)
- Works better (more power) when tuned on the lowest channels

- Kills 2.4Ghz RC range in some situations.
To solve the problem: use 1080Mhz (helps a bit), if not use a low pass filter:
900Mhz (if you are on 1080) or 1.2-1.3Ghz 42USD i.sh.

NEW Cheaper Filter

20 USD Including shipping

Other solutions: Change your 2.4Ghz RC antenna to a 8Dbi Patch and/or use a Wifi booster.

Auto Scan Mode

Quickly press and release either control button (up or down) till you get to the first channel that you want to monitor. Then press and hold either control button until you see the dot, like "6." instead of just "6". Repeat with other channels that you want to monitor until you have selected all the channels you want to monitor.

Quickly press and release either control button (up or down) till you get to the "A" channel and leave it there. Soon it will change to the first selected channel and then the second... On mine, with no antenna, and no signal, it plays each channel about 6 seconds and then jumps to the next channel.
hello
can you help me with a very good combo off all i need to go fpv with my octo
i have today the 5,8 ghz fvp gear,but i get alot off noise in the camera,i have ferit on all off my esc and have placed it so fare away from everything so i get it,but i need a better system how penetrate better then the5,8
i am flying in the forest and stuff liek that and want a good system for it,can you help me with links to everything that a need 1,2 og 1,3ghz??

thanks
kjetil tønnesen
norway
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Old Apr 15, 2011, 03:59 PM
RC pilot by soul
Israel
Joined Apr 2005
2,494 Posts
Hey guys,

my first FPV model is a Funjet with a BOB 800mW 1.2Ghz set.
i test flew it this morning in a deserted field and flew 4 gret flights with 0 problems. so i went home, installed my DVR on the Rx tripod (next to Rx) and went out to the local RC flying field.
This time i had a problem where the picture freezes sometimes for 3-4 seconds as can be seen on the video i recorded:
My first attempt at FPV - Multiplex Funjet (10 min 56 sec)


What do you guys think can cause this and how do i avoid is ?
is it related to the DVR being close to the Rx or to the fact that the video signal is now passing through the DVR ?
or could it be related to outside interference of some sort which i didnt have at the deserted field i did the test flight in ?

thanks for your comments.

PS - it cause a small carsh on flight #2 when the video froze in the middle of a low altitude roll.. hehe !
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Old Apr 15, 2011, 04:59 PM
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Luxembourg
Joined May 2009
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do not pass the video to the dvr, split the video instead with an onvon video splitter or just splice the video cable (can be only made for 2 outputs)

kjella: just read.... Regarding the analysis the RC community made, the current suggestion of the chef is: Fox-800 (see 2nd Post)

so buy the fox 800 combo and get yourself some good antennas
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Old Apr 15, 2011, 05:36 PM
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Lakewood, Colorado
Joined Aug 2002
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And just so it's clear, the signal coming from the camera through the Tx to the Rx itself
cannot freeze. It's pure analog so always displays in realtime.
It had to be happening in the DVR. Looks like it doesn't like more than a little static.

ian
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Old Apr 15, 2011, 06:17 PM
RC pilot by soul
Israel
Joined Apr 2005
2,494 Posts
Quote:
Originally Posted by Daemon View Post
And just so it's clear, the signal coming from the camera through the Tx to the Rx itself
cannot freeze. It's pure analog so always displays in realtime.
It had to be happening in the DVR. Looks like it doesn't like more than a little static.

ian
that makes sense ! i will change the video connection to parallel instead of passing through the DVR.

any chance the DVR is interfering with the Rx ?
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Old Apr 15, 2011, 06:29 PM
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Lakewood, Colorado
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Quote:
Originally Posted by i3dm View Post
any chance the DVR is interfering with the Rx ?
No. Even if it was, it wouldn't make the picture freeze. That's why I posted what I did.
Your video and link quality are really quite good. Your DVR just isn't suited to FPV.

ian
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Old Apr 15, 2011, 06:37 PM
RC pilot by soul
Israel
Joined Apr 2005
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Quote:
Originally Posted by Daemon View Post
Your DVR just isn't suited to FPV.

ian
What makes it not suited ? and can you recommend a different one ?
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Old Apr 15, 2011, 06:53 PM
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Lakewood, Colorado
Joined Aug 2002
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It freezes up when it sees noise. I thought that was pretty obvious by now.
The problem is, it's likely to do it when you need it the most, say you have a problem
and your plane goes down far away. Edge of range, poor LoS, bad antenna orientation
will produce noise, and then your recorder freezes up and you have no idea
where the plane goes down.

There's a HUGE recorder thread with lots of usable options. My choice is the most
expensive one, so I'm not going to offer it here.

ian
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Old Apr 15, 2011, 06:56 PM
RC pilot by soul
Israel
Joined Apr 2005
2,494 Posts
Quote:
Originally Posted by Daemon View Post
It freezes up when it sees noise. I thought that was pretty obvious by now.
The problem is, it's likely to do it when you need it the most, say you have a problem
and your plane goes down far away. Edge of range, poor LoS, bad antenna orientation
will produce noise, and then your recorder freezes up and you have no idea
where the plane goes down.

There's a HUGE recorder thread with lots of usable options. My choice is the most
expensive one, so I'm not going to offer it here.

ian


Thank you. again, that does make sense.
the strange thing is that usually when i fly overhead (with omni antenna) there is a little noise thats visible in the video, and its still visible through the DVR with no freezing.
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Old Apr 15, 2011, 07:00 PM
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Lakewood, Colorado
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It's a matter of degrees. Test it around your house with the Rx antenna removed,
and it'll happen all the time.

ian
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Old Apr 15, 2011, 07:04 PM
RC pilot by soul
Israel
Joined Apr 2005
2,494 Posts
Will try that. thanks !

either way sounds like the safer way is to parallel the videos and not feed through so i will change that.
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Old Apr 16, 2011, 02:15 PM
RC pilot by soul
Israel
Joined Apr 2005
2,494 Posts
Quote:
Originally Posted by Daemon View Post
It's a matter of degrees. Test it around your house with the Rx antenna removed,
and it'll happen all the time.

ian
Ian,

just to inform you that you were 100% right - we varified today that the problem is in the DVR.

Thank you for your help !
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Old Apr 17, 2011, 08:18 AM
DragonLINK UHF only!!!!
Joined Feb 2011
1,218 Posts
concerning the LawMate VidTx 1.3ghz ....is 1000mW too much/overkill?????

http://www.dpcav.com/xcart/product.p...cat=279&page=1

or should I just go with the 1.3ghz 700mW ?

http://www.readymaderc.com/store/ind...roducts_id=324


What ones have worked out great without any issues?
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