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View Full Version : Let's talk 5.8ghz FPV camera setups



DresnerRobotics
01-08-2013, 09:11 AM
Alright guys, I've been doing a lot of research on FPV (First-person-video) setups. Currently I'm going to be testing an examining 1.2ghz and 5.8ghz setups. Disclaimer: These will technically require at least one person onsite to have a HAM or Amateur Radio Tech license, which I plan on attaining. If you plan on doing your own personal testing at home, please check local laws, etc etc.

There is a very nice, very powerful 5.8ghz transmitter receiver that I've found and am ordering samples from. I'll also be ordering a couple of camera samples but some are small enough to fit on your fingertip, which will make for fantastic mounting options.

Here's the TX/RX. The TX weighs about 67g or so.

4450

Here's a video with a less powerful transmitter and standard antenna so that you can see what interference/out of range on these systems look like. Keep in mind these are rated for literally kilometers, so at our range any interference will be minimal:


http://www.youtube.com/watch?v=KeLf3CFTPjo

Here's a video with a proper antenna setup & in range, and better camera, and as you can see, much less interference:


http://www.youtube.com/watch?v=em-_p9NsQrU

Cameras make a good difference here. I've found some top-of-the-line Sony 700 TVL resolution cameras that are a bit spendy but otherwise awesome.

The retail on a total transmitter/receiver/hi-res camera will be roughly $250-300. If I could get them for the Trossen Store, would people be interested in pre-ordering to get one?

Overall, here's the breakdown on this type of camera setup. I plan on using it in conjunction with my existing Wifi IP camera for redundancy, possibly eventually moving my IP camera to my rear for an additional camera view.

Pros:

Modular and compact.
Long range (>1km)
Separate camera, choice of camera.
Video output much easier to capture/broadcast/record.
Virtually no interference with 2.4ghz (nothing at RG uses 5.8).
No framerate drops or outright connection drops.
No hassle with router/IP.
Up to 9 channels supported.
Can be used as redundant video feed.
Cons:

High power consumption
More expensive
Untested at RG
Requires either a USB capture device or TV monitors, so more Mech Warfare infrastructure cost.
Thoughts, questions, comments?

jwatte
01-08-2013, 10:58 AM
Those look pretty great in broad daylight! I wonder how they perform in lower light? One of the webcam problems is that they lower their FPS in low light situations. If I remember the 2012 setup, the inside of the arena might have some dusky corners. I wonder if these cameras are higher quality than the webcams for that?

KevinO
01-08-2013, 11:25 AM
I use a similar setup on my octocopter with a GoPro transmitting the SD signal as well as recording in HD. You are right about the camera. I used a cheap camera before the GoPro and was amazed what a decent lens made after I switched. Another feature if you were inclined would be the ability to add a HUD if you were technically skilled.

DresnerRobotics
01-08-2013, 11:52 AM
Those look pretty great in broad daylight! I wonder how they perform in lower light? One of the webcam problems is that they lower their FPS in low light situations. If I remember the 2012 setup, the inside of the arena might have some dusky corners. I wonder if these cameras are higher quality than the webcams for that?

The cameras I'm looking at specifically cite that they work well in low-light conditions. These are much higher quality cameras than the IP-cams in general. We didn't have these so readily available in the first 2 years of Mech Warfare, but thanks to the FPV/Quadcopter/RC Air industry, we now have a ton of options and frequencies at reasonable prices.

Upgrayd
01-08-2013, 05:14 PM
would people be interested in pre-ordering to get one?

I am interested and am willing to pre-order. I would like to have at least a test setup running at Robogames this year for evaluation.

Th232
01-09-2013, 05:20 PM
I'd be interested in the camera at the very least, and a 5.8GHz setup pending a review of the import laws. 1.2GHz requires a license though.

kamondelious
01-09-2013, 06:11 PM
I'd be willing to pre-order.

:)

KevinO
01-09-2013, 10:38 PM
I'd pre order as well

Slugman
01-09-2013, 10:39 PM
After I zapped my camera I have been investigating these as well, & came to the same conclusion. 5.8Ghz is the only one of the options legal for me so I was going to go with the 600mW, but there seems to be difficulty getting some Fatshark / ImmersionRC products down here - Specifically the Uno receiver. I didn't look at trying to combine different systems, as there seems to be limited combinations of products that work together.
Andrew, if you can get packages of complete 5.8Ghz FPV setups that work, then I would also be happy to pre-order.
You might want to clarify if these can be used with goggles etc, & if so, then which goggles are compatable with the FPV setup. I only want to use a screen, but it might be useful for others if they want to upgrade.

Incidentally Andrew, I only started looking at the FPV stuff after I saw you wearing goggles in a photo of Mech Warfare 2012, so I assumed you were already using it, with head tracking. :)

Th232
01-09-2013, 10:47 PM
Well, if Slugman says that they're fine down here, then definitely chalk me up for the 5.8 GHz setup.

Slugman
01-09-2013, 11:34 PM
Well, that's what I've heard..... :) I got most of my info from FPVLAB.com & RCGroups.com
I have been trying to get a kit from here;
http://www.mongrelgear.com.au/the-mongrels-shop.html?page=shop.product_details&flypage=vmj_color_plus.tpl&product_id=123&category_id=31

but it's been out of stock for ages. He's trying, but can't seem to get the stuff to sell on. There's info on that site re the legalities etc down here. The FPV guys try to get the most distance they can & so they are pushing the limits by using the lower frequency stuff like 1.2Ghz. The 5.8Ghz won't work around corners, but at least it's legal for us to use.

Slugman
02-03-2013, 04:21 PM
Sorry Tybs, I went & ordered a set locally for 5.8Ghz, as it was a fairly decent deal for my use, & I can upgrade to the HoryzonHD V3 camera later.

DresnerRobotics
03-21-2013, 01:32 PM
I realize this is getting late here, but I just now got in 5.8ghz gear. It's fantastic so far, I really see it as a totally viable alternative to 2.4ghz wifi. I'll be posting a full video review, there are some 'catches' to it but overall the benefits vastly outweigh the negatives.

NO LATENCY IS AMAZING FOR PILOTING/AIMING!

DresnerRobotics
03-21-2013, 03:50 PM
http://www.youtube.com/watch?v=1p3CK3hJM3E

Quick video for now.

Pros:

Modular, compact design. Camera + transmitter are separate, making camera mounting MUCH easier and more versatile.
No latency whatsoever.
Image quality is fantastic.
No framerate disruption at all.
12v operation, easily powered from a 3S lipo.
Setup literally takes seconds.
9 channels available, virtually no interference from 2.4ghz.
Video output options such as 7" LCD displays with integrated 5.8ghz receivers are available.
We can easily record all FPV video from mechs running 5.8ghz, also split it out for audience to see.
OSD (on screen display) should be pretty simple to add as well. There are overlay modules everywhere.
Cons:

Breakup/static occurs when moving or just randomly. It's not a deal breaker but it's the biggest flaw of this. See video for example. May be addressed through use of Cloverfield antennas (on their way to me now).
Not quite as 'plug-n-play' in terms of wiring as IP cameras. You'll have to hack apart the supplied cables to get rid of the unneeded RCA plugs.
Cost. This is definitely a more expensive setup. I'd say a high-quality camera/transmitter will run $300 retail, with cheaper options coming in around $200.
Antennas are going to be clunkier/larger.

jwatte
03-21-2013, 04:58 PM
What about camera channels? Is there interference between multiple cameras?

And, if I need the camera input for semi-autonomous operation on the mech, but still want to use the 5 GHz band, can I use wireless-N on the 5 GHz band? How does interference between that and the 5 GHz cameras work?

CogswellCogs
03-21-2013, 05:09 PM
Very intriguing idea. I would love the no latency thing. One more con; there's no easy way to integrate the video into your software. I assume you'd need to digitize it out of the 5.8 Ghz receiver and stream it into your code. With WiFi video, the video is already digital and ready to consume that way.

DresnerRobotics
03-21-2013, 07:44 PM
Very intriguing idea. I would love the no latency thing. One more con; there's no easy way to integrate the video into your software. I assume you'd need to digitize it out of the 5.8 Ghz receiver and stream it into your code. With WiFi video, the video is already digital and ready to consume that way.

It's as easy as a $20 USB adapter. Getting some of those in too.

DresnerRobotics
03-21-2013, 08:00 PM
What about camera channels? Is there interference between multiple cameras?

And, if I need the camera input for semi-autonomous operation on the mech, but still want to use the 5 GHz band, can I use wireless-N on the 5 GHz band? How does interference between that and the 5 GHz cameras work?

Moved ya over here to keep the camera discussion separate from rules.

You can theoretically run up to 9 cameras at once, there's enough difference between the channels (reportedly, I don't have enough cameras to verify). The 3 setups I have here run simultaneously as far as I can tell- only have one old school TV at the moment, so can only view one at once but it doesn't appear to be affected by the other two transmitter/receiver units.

Wireless-N is still restricted. We're going to keep Wifi at 2.4ghz, and analog video at 5.8ghz. Wireless-N will channel hop and pollute the entire band. I'd rather have 9 analog cameras than 1-2 wireless-n devices available to us.

Slugman
03-21-2013, 10:43 PM
One problem with 5.8ghz is signal loss due to a blocked signal path so 5.8 is usually used line of sight (LOS). Have you tested what interference the M-W buildings will have when the bot is behind them on the far side of the arena?
Not trying to be devils advocate, just not sure if there's gonna be an issue with tx placement for you guys competing.

DresnerRobotics
03-22-2013, 12:05 AM
I think that's a problem with lower power transmitters. The 600w has signal strength all the way to the back of our building and to the end of our parking lot. That's with omnidirectional antennas and through multiple walls and solid doors. Sitting within 20 feet and only going through plastic should not be an issue. Worst case we can mount receivers inside the area and just run the video out.

jwatte
03-22-2013, 01:20 PM
Wireless-N is still restricted. We're going to keep Wifi at 2.4ghz, and analog video at 5.8ghz. Wireless-N will channel hop and pollute the entire band. I'd rather have 9 analog cameras than 1-2 wireless-n devices available to us.

That's unfortunate, as I really do need the video on the actual 'mech. I can stream over 2.4 GHz from the 'mech computer, but as you said that spectrum is iffy at RoboGames, I had hoped that 5 GHz Wireless-N might be an option.

DresnerRobotics
03-22-2013, 03:22 PM
That's unfortunate, as I really do need the video on the actual 'mech. I can stream over 2.4 GHz from the 'mech computer, but as you said that spectrum is iffy at RoboGames, I had hoped that 5 GHz Wireless-N might be an option.

Sorry, I'd nixed it even before the introduction of 5.8ghz analog cameras due to it's channel hopping nature. Honestly the 2.4ghz network equipment is far better than what you would have available with your own 5.8ghz gear, unless of course you're investing in a $1200+ router.

Gausswave
04-05-2013, 02:02 AM
That's one thing analog will always have over digital is " real time ". You might also think about getting real antennas in the arena. You could have it be part of the building models! Do you have any control over the power level? If so you could bring it down into the part 15 range and you wouldn't need a ham license. Also you'll need a way to add the Ham ID to the video to be legal. The other thing to consider is media at the event may be using the same freq. Hams are secondary users on those bands if IIRC. It's been a while since I was tested on that. KB7WNZ.

DresnerRobotics
04-23-2013, 01:59 PM
Well, tested all weekend at Robogames with great success. There is some inherent mild interference and signal quality that comes with using 5.8 indoors, but overall the performance is incredible. The systems are light/compact enough that they can be added to mechs with existing 2.4ghz wifi ip cameras for a redundant video feed (or perhaps a rear-camera?).

We've nailed down the best offerings here and will be stocking them in the store shortly.

fractura_laniatus
04-23-2013, 04:27 PM
It's as easy as a $20 USB adapter. Getting some of those in too.

So if I am reading the crystal ball right we should be able to stream the digital data to our control program similar to the current wi-fi webcam solution. Have you tested the latency on the digitization of the analog signal via USB adapter yet? I can't image it will be worse than the current wi-fi webcam systems in use. The only bottleneck I see is the speed of the adapter and the host computer's USB bus.

DresnerRobotics
04-23-2013, 04:32 PM
So if I am reading the crystal ball right we should be able to stream the digital data to our control program similar to the current wi-fi webcam solution. Have you tested the latency on the digitization of the analog signal via USB adapter yet? I can't image it will be worse than the current wi-fi webcam systems in use. The only bottleneck I see is the speed of the adapter and the host computer's USB bus.

I haven't tested it explicitly yet (as in trying to get a sense of the mS delay), but have hooked it up to the one I have here and it was not at all even noticeable. I'd imagine it's a few mS at most.

bloftin
06-07-2013, 03:43 PM
How much longer until they are stocked? If we drool much longer the wives will start to complain :)


Well, tested all weekend at Robogames with great success. There is some inherent mild interference and signal quality that comes with using 5.8 indoors, but overall the performance is incredible. The systems are light/compact enough that they can be added to mechs with existing 2.4ghz wifi ip cameras for a redundant video feed (or perhaps a rear-camera?).

We've nailed down the best offerings here and will be stocking them in the store shortly.

DresnerRobotics
06-07-2013, 04:35 PM
Basically, we had some problems with the 7" LCD Receiver performance which held things up. It kept dropping the signal and wouldn't reconnect. Upon speaking with the manufacturer, they confirmed there was a defect with the receiver chipset were using, so it's being completely upgraded and replaced with a higher performance once manufactured by FatShark (who also make goggles, etc). We were waiting to hear a word on when these were going to be available, and as of last night I was told August.

So the current plan is to move ahead with just stocking TX/RX combos that DO work, and some cameras to go along with those. No fancy 7" LCD receivers for now, but we'd rather only stock stuff that we know works well. I'd put it at 2-3 weeks out from this point forward.

In the meantime, I've done some extensive testing on the TX/RX combo units we have along with our buddies at MadLab Industries, and we've come up with an incredibly robust receiver solution that I'll be integrating into the arena much like our existing Wifi setup. We had a quadcopter 350 feet in the air and probably 1000 ft away from our location and had a perfect video signal.

K1LD4R
06-08-2013, 10:46 AM
So for competition we won't need our own receiver, just the transmitter on our robot? The receiver would be necessary for testing of course, but it wouldn't need to travel to Chicago then. I'm coning from the Washington D.C. area, so equipment weight may be a consideration depending on which airline I fly.

DresnerRobotics
06-10-2013, 03:17 PM
The receivers weigh a whopping 2oz, so that's not really the issue. But yes, we'll have our own integrated receiver network much like our existing wifi network.

Edit: unless you're talking about the 7" LCD receivers, in which case these will NOT be provided to competitors. The setup that will be provided will be fed into 27" LCD screens for competitor use.

Xevel
06-13-2013, 06:58 AM
I've been looking around at cheap 5.8GHz FPV stuff on Hobbyking and Alibaba, and sometimes they mention that this or that part is not compatible with Fat Shark products.
So since not everything works together, do you already know what brand/model of receiver you will integrate in the arena, so I can buy equipment that will most probably work with it? I'm working on a Mech with very little room inside and just swapping the emitter at the last minute is not really an option (they don't look like they have a standardised size), I need to integrate it tightly in the design from the beginning.

tosjduenfs
06-13-2013, 11:58 AM
Hello Everyone,

My name is Mike, I live near Chicago. I'm currently designing a Mech for the 2014 competition. I've been flying multirotors FPV for a while now and have some experience with this equipment. I've never used 5.8GHz specifically but I think some of my experience still applies.

As far as Xevel's question goes it might be best to post what frequencies the Rx will be capable of tuning into since most Txs list what frequencies they emit. Also, I assume NTSC will be used but it may be best to specify that as well since most of this equipment comes from China which uses PAL.

The greater power a Tx has the more interference it will have inside of a building leading to more gray outs of the video. I would think that 200mw would be highest you'd want to go considering how close you'll be to the mechs. Also from my experience the higher power transmitters get very hot and are more prone to failure than less powerful ones.

Circularly polarized antennas can help tremendously in interference rejection. The first and strongest reflection off of a wall will have its polarity reversed making it nearly invisible to the Rx. Since every reflection is reversed, CP antennas can reduce interference by more than 50%. The only issue with widespread use of CP antennas is that you would have to specify the use of left or right handed polarization.

I could see a problem with people powering up their mechs when not competing and interfering with a competitor's video feed.

Just a few thoughts.

Regards,
Mike

ArduTank
06-13-2013, 10:46 PM
Tosjduenfs, a lot of the video capture devices we can get have support for both NTSC and PAL. And a lot of TV's have support for both too.

tosjduenfs
06-14-2013, 05:41 AM
That's true Ardutank, I was more concerned about the protocol used for the community Rx installed at the competition. I've always bought NTSC components so I'm not sure if a PAL Tx will work with an NTSC Rx or if the NTSC/PAL system only comes in at the output of the Rx.

jwatte
06-14-2013, 11:06 AM
All the systems I've seen are "PAL/NTSC compatible." It's pretty easy to make mostly the same circuitry do both, and if you're selling on a world market, there's no reason not to do that. Back in the days of vacuum tubes, not so much, but that's kind-of behind us by now :-)
This is not a guarantee that any particular device you find will work, but the format confusion problem is much diminished compared to twenty years ago.

ArduTank
06-14-2013, 02:37 PM
If they are as compatible as Tyberius is saying, then the NTSC/PAL encoding comes in at the output of the receiver, not before.
A little like this:

Camera, (NTSC or PAL or Other) >>> TX>>> 5.8GHz Spectrum Protocol >>> RX >>> Final Output (NTSC or PAL or Other)

Xevel
06-14-2013, 07:56 PM
Yeah as far as I can tell, between the emitter and the receptor, it's simply a modulated analog signal (hence the limit to one emitter per frequency compared to digital stuff like wifi that can accommodate lots of emitters), so it seems to be completely agnostic to what it's transporting.
The output of a receiver is an analog video signal, the same as the one input in the emitter except for distortions/noise/filtering. So PAL/NTSC is an issue only if the visualization equipment (LCD, VR goggles, USB Analog video adapter(?) ) does not support the one your camera outputs.

And what I understood from Tybs' (http://forums.trossenrobotics.com/showthread.php?5909-Let-s-talk-5.8ghz-FPV-camera-setups&p=58301#post58301) messages (http://forums.trossenrobotics.com/showthread.php?5909-Let-s-talk-5.8ghz-FPV-camera-setups&p=58341#post58341) was that the arena would have a receiver+antenna, and you can put whatever you want at the end of the Analog Video (RCA?) cable. The question is which set of frequencies will be used, and it seems to me that the newly added FrankenCommander article (http://forums.trossenrobotics.com/robots.php?project_id=55#ad-image-0) spills the beans:

RC701 7" LCD 5.8ghz video receiver unit (soon to be stocked in the Trossen Robotics store)
From the product page, this receiver uses the following frequencies (as strange as they may look... :/) EDIT: As Tyberius says below these are NOT the frequencies used!


CH1: 5705Mhz
CH2: 5685Mhz
CH3: 5665Mhz
CH4: 5645Mhz
CH5: 5885Mhz
CH6: 5905Mhz
CH7: 5925Mhz
CH8: 5945Mhz



I'm going to wait for Trossen to stock the stuff before buying anything, but from reading avidly FPV forums in the last few days, I'm not sure I will go with such an overpowered emitter as the ones that have been talked about so far.
600mW? seems a little bit overkill when people get kilometers of range out of a 200mW one, with the proper base station antenna... and all the more when the only CE certified ones that don't require any licence are 25mW. We're going to be meters away from the robots.
Flying Line-of-Sight is a very different thing than having an indoor environment though it seems, and there's a lot less information on that kind of case.


Also from the product page of the receiver:



Can receive 2 different channels at the same time

I smell the "quit looking at my feed!!!" cries coming... that should not we too hard to do to have a quick peek at what the other bot sees! xD (just kidding, we are all playing fair are we?)

DresnerRobotics
06-17-2013, 02:35 PM
Actually those are NOT the frequencies we'll be using. The 'product page' you found could just be anyone reselling these units, and you specify from the manufacturer which of the 4 frequency sets you want. We're using Channel Group #4, which is the same as the Fat Shark headsets.

I have likewise read about the 200-300mW transmitters being ideal, but so far based on my own real-world testing at Robogames the 600mW units had no interference or bouncing issues whatsoever. I'll likely bring in some 200mW units to test with as well, but the 600mW units are staying for use with our upcoming UAV Quadcopter offerings. :)

Xevel
06-17-2013, 03:17 PM
Sorry, my bad!
I made a little too many assumptions, I'll try to refrain from that next time ^^

DresnerRobotics
06-17-2013, 05:12 PM
Sorry, my bad!
I made a little too many assumptions, I'll try to refrain from that next time ^^

Hey no worries.

Again, I mean what I've read about not needing higher power and it actually being somewhat detrimental makes sense... but so far my real world testing hasn't really shown any difference.

"Point blank" reception from the 1200mW vs the 600mW really hasn't shown any difference at all. The 1200mW unit I was testing with on my quad at the last RG wasn't suffering from any interference regardless of how close I was, even in the arena where it should theoretically be bouncing signals off of the walls. 5.8ghz was noisy at RG this year too, as they upgraded their routers to support that frequency.

Dunno, like I said, I acknowledge what people are saying 'in theory' but so far my real world testing has shown no signal degradation or interference with higher power transmitters in close-quarters/short distance.

Xevel
06-17-2013, 06:53 PM
Ok, cool :)
The video quality was indeed amazing at RG, I'll give you that!
Can't wait for these items to be in the TR store!

jwatte
06-17-2013, 07:33 PM
Hmm. What if I make my BBs out of compressed metal strips, that unfold to about 5.5 cm length on target panel hit... ;-)

ArduTank
06-18-2013, 10:15 AM
You'd never hit anything because the bbs would unfold before hitting the target and the larger air contact surface would set them off course/ stop them in midair.

tician
06-18-2013, 11:19 AM
You'd never hit anything because the bbs would unfold before hitting the target and the larger air contact surface would set them off course/ stop them in midair.
Unless you roll them up into cylinders and place them within a somewhat aerodynamic, spring-loaded shell that releases/ruptures upon impact to disperse the strips. Or any of dozens of other designs that seem to be pooping into my head...

K1LD4R
06-18-2013, 05:16 PM
I'm pretty sure dropping things that interfere with a contestant's mech is against the rules. :tongue:

jwatte
06-18-2013, 07:32 PM
But this is ammunition, not chaff! And it's interfering with the radio, not the mech! And rules lawyering is what the competition is all about, right? ;-)
/me ducks before being perma-banned

ArduTank
06-19-2013, 12:44 PM
Tician, then the BBs would end up being the size of a Nerf dart.

And they're pooping into your head??

tician
06-19-2013, 03:22 PM
Tician, then the BBs would end up being the size of a Nerf dart.
Depends on the dimensions and quantity of the metal strips used...

And they're pooping into your head??
It was originally "popping" but first typed "pooping," and upon rapid realization/examination, it seemed far more appropriate than the initially intended word, so let it be.

ArduTank
06-19-2013, 04:32 PM
You'd have to design it like a paintball to make it small enough to shoot out of an airsoft gun. And they'd be very expensive on top of that.

Only reason I said anything about the pooping ideas was because it made me lol.

darkback2
06-20-2013, 12:40 AM
Has anyone else setup one of these cameras? I got all excited and got a boscam RX/TX and a cheap sony camera from god knows where...It is pretty light weight and has a decent range though I think its only 200 mw...It works well enough around the house thought the refrigerator seams to be able to cut the signal to nothing in a heart beat. I was able to move the robot around while it was upstairs and I was downstairs.

The antenna sort of sucks, and in time I will probably order whichever system we find to be the most reliable. In the mean time I will be swapping out the antenna on this guy for a 5.8GHz Circular Polarized spiroNet Antenna to increase the range.

One nice thing is that this guy is A...tiny, and B runs on a 3 cell lipo which makes hooking it up on an AX-12 based bot convenient.

DB

Xevel
06-20-2013, 03:06 AM
Haven't made the step yet for the TX/RX (waiting for TR to put their offering online to get the "official" ones), but I have ordered interesting extra small cameras that I suspect won't be in the TR store anytime soon (quality seems to be a lot lower than what was on Tyberius' quad at RoboGames). Still they will serve their purpose, just not as "main" cams...
I'll test them and start developping things around them (multi-cam switching, maybe a custom OSD) as soon as I get them, since I don't need the TX/RX to do that.

The fact that the fridge kills your signal is exactly what I expected, thanks for the info. I have also been wondering about the problems that the bot itself might create for the signal propagation (reflexion or occlusion from metal/carbon plates of the chassis)... on which bot did you make this test? IIRC your bots are mostly aluminum, aren't they?

darkback2
06-20-2013, 11:57 AM
4827

This is X. The camera lense is poking out of the 3D printed head. There is a bit of a shadow in the display from it which almost looks like a virtical hold error. The camera is a cheap sony that came with the TX/RX setup. The whole thing runs on 12 volts. You can see the streight antenna poking out from underneath the plastic casing by the front right leg.

4828
In this pic I removed the head, plastics, and metal plate that sit over the transmitter. I put a ruler next to it for scale. I probably could have tucked this into the body if I wanted to given that there is plenty of room, but I had different purposes for putting it where I did. As soon as possible I will be swapping out the antenna.

Currently the video works if the robot is upstairs and the receiver is downstairs. Again, if I put the robot in the kitchen which is closer the refrigerator kills the signal. Moving away from the refrigerator brings the signal back. I haven't done a range test outdoors or with direct line of site, but I would imagine it would be greatly improved. I also expect using an omni directional antenna to make quite a difference.

Again, I will probably end up getting the trossen setup for my other robots, I just really wanted to get a move on on this project.

Xevel
06-20-2013, 03:14 PM
Cool, thanks darkback2 :)

On a side note about 12V cameras : today I learned some of them are really 5V cams with a shitty 5V linear regulator (http://www.dealextreme.com/customerphotos/quarantined/201108/44679-ced1b9c0-40a7-4eef-950f-97d7059d8225.jpg).

darkback2
06-20-2013, 09:06 PM
yeah...that is probably the case for this one. There were some other issues like the video plug on the camera was installed backwards switching the video and negative wires. I think I payed about $60 for the whole package on sale online...Shipping took about a month...I know you get what you pay for so I am not expecting much.

K1LD4R
06-21-2013, 02:49 PM
This unit is pretty darn pricey, but it at least appears to be extremely small and high quality. I think I'm going to use it for my mech.

https://www.sparkfun.com/products/11418

darkback2
06-21-2013, 08:39 PM
The cool part about that is you could record HD video from your mech's point of view.

ArduTank
06-21-2013, 09:57 PM
Nice. Little pricey though.

jwatte
06-22-2013, 12:03 AM
The cool part about that is you could record HD video from your mech's point of view.

You can do that with a Microsoft HD 3000, too, as long as your WiFi is Wireless-N :-) (Which can run in the same band as the analog 5 GHz video)

Xevel
06-22-2013, 01:25 AM
The cool part about that is you could record HD video from your mech's point of view.

Or you could do it with a GoPro (using it as the FPV cam at the same time as recording), for even more money! ^^
And if it's a Hero 3 Black, you could even have yet another feed in wifi, with this time a free 2s of lag!

tosjduenfs
06-22-2013, 02:30 AM
This unit is pretty darn pricey, but it at least appears to be extremely small and high quality. I think I'm going to use it for my mech.

https://www.sparkfun.com/products/11418

Does the spec sheet say what the latency is for the composite output? I didn't see it. I had issues trying to use my GoPro as my FPV camera for my multicopter because there is a noticeable lag on the video output. If the hackHD has any lag on the video output it will not be good for remote piloting.

jwatte
06-22-2013, 12:48 PM
I would expect that the composite output is taken straight from the analog sensor, so lag is on the order of one scanline.
However, if the camera has to re-generate that signal from digital framebuffer, then lag could be a frame.
For embedded electronics, keeping more than one framebuffer in RAM is an unnecessary cost, so I'd expect it to be no more than that from an engineering point of view.
I'd also expect the lag on the GoPro to be almost entirely in encoding, as it probably uses a deeply pipelined video encoder, and if it uses bi-directional frame prediction, it can need a lot of buffering for that. Was that 2s of lag using H.264 or MPEG-4 by any chance?

Xevel
06-22-2013, 05:16 PM
Was that 2s of lag using H.264 or MPEG-4 by any chance?

2s of lag is what I get when I look at the video output of the cam with the official GoPro Android app on my phone (it has a dual core 1.2GHz proc and theoretically some hardware decoding capabilities).
I didn't look into the details, VLC has some problems reading the feed (only reads a second then stops), so I stopped playing with it pretty fast., and just used the cam for its intended purpose. This functionality is more of a preview so you can adjust the position/orientation of the cam, not intended for monitoring/fpv.
Haven't tried the AV output (I don't have any connector to access it yet, you need either a 10pin mini USB B or the 30 pin ipod-like proprietary connector), but it seems that some people use the GoPro for FPV so I would expect the delay through this channel to be reasonable. This guy (http://www.youtube.com/watch?v=wAJVitoGysQ) says it's about 100ms for a GoPro2, which might start to be noticable, even more when you add the transmit delay.

tosjduenfs
06-22-2013, 08:31 PM
With my original GoPro composite output hooked up directly to the tv I probably get about 1/4 second of lag.

giantflaw
10-09-2013, 10:35 PM
How is the Trossen analog video transmitter and receiver selection going that will eventually be stocked? I think in June, August was mentioned as a probable date for selection. Now it's October and I was wondering how it's going.

byi
01-13-2014, 02:25 AM
So, I am currently looking around for a camera setup, and i need to be able to bring down the price as much as possible. I noticed a pretty steep price difference depending on transmitter power and camera resolution. What would you say are the minimum usable values for this or any other factors that might affect reliability and price?

ArduTank
01-13-2014, 07:53 AM
Camera resolution is to each his own, but you don't need a 1 watt transmitter, less should be fine (short range ), however, I wouldn't skimp on the reciever quality.

Correct me if I'm wrong please.

Xevel
01-13-2014, 10:42 AM
Well, I started writing a review of the few cams and emitters I have, but got interrupted by the rest of life (that things always gets in the way).

To answer very quickly your questions:
Resolution is very important, sensor type is too. I have tested shitty 380TVL to nice 600TVL CMOS and a 420 TVL CCD.

If you have spot light sources in the field of view, CCD wins, since you can still see fairly well the rest of the picture instead of having a big white spot surrounded by blackness.
I have recently received the Fatshark CCD Killer (which is a CMOS) but haven't tested it yet :/

Resolution makes a lot of difference when looking at something 3m away. Don't expect precision aiming with a 420TVL. 600TVL is noticiably better but still not the HD quality we are accustomed to nowadays...

So far the best budget cam I have used are the 12x12mm 600TVL CMOS bought on DealExtreme for around $20 each. I have fisheye and pinhole versions, both with their uses. Fisheye gives a good large view but is shitty for aiming, pinhole has around 90° horizontal FOV and is OK for general purpose usage I guess.
If I had to put only one cam on my bot, that would be it. I think the setup Tyberius had at the last Robogames (the quad with the FrenkenCommander) had a similar cam.

In terms of Transmitter and receiver, I don't really know. I have a Fatshark 100mW TX and ImmersionRC Uno 5800 (moddedforacceptablesoundgoddamnit). Alone in my house, with only a single WiFi AP around, it does work pretty well even between (wooden) floors. I've read somewhere that having a lower power TX can be beneficial indoors as it lowers the intensity of the self-interferrence (reflected signal arriving at different times: multi-pathing)... I haven't tested yet.
I also have 3 modules of different power from Airwave, a 10mW one, a 100mW one (that's what's inside the Fatshark TX I have), and a beefier one. I haven't tested them yet though, but I received all the components to do it, so might get to it. I'm pretty sure that for less than 5m with line of sight, even the lowest power one will work nicely in a calm environment, but I fear that if anyone has a much more powerful one with a badly tuned setup, it will smear noise all over my frequency and kill my SNR :(
I think that would be a good thing if the transmit power chould be limited in the rules so that everyone transmits with the same, reasonable power :/


In terms of receiver, even less sure there. A "simple" one like the Uno 5800 is already quite pricy. You obviously need one for developping and testing, but iirc Tyberius will have big ones with diversity (multiple antennas to receive the same signal, which should help a lot in getting a clean signal indoors) around the arenna, so you might not need to invest much more than that. Need confirmation of Tybs.
I also got an RX module, not tested either. Creating a full receiver from the module seems to be mostly about two things: quality power supply and video buffering, both of wich can be cheap if you buy the components and know what you are doing. I wouldn't bother though - just get a reasonable one from the start.



In terms of antenna, circularly polarized (spiroNet and the like) definitely beat the rubber duck antennas indoors. I have thick stone walls here and with the origianl rubber duck, had a lot of interferences (signal dropping) when I moved around. The interference zones are much less important (in size and in intensity) even with dirt cheap chinese cloverleaf/skew planar pairs. I haven't had time to compare to my new SpiroNet v2. Pretty sure Tybs had Fatshark/immersionRC spiroNets on his quad at RG. Haven't tried anything else but that seems to be the best there is in terms of omnidirectional antennas at a low price point...
Given that the bots are in a very limited zone (constant height, fairly little area, we could maybe have a look at some more directional antennas for the RX...
Anyway, going with the cheap ones (dealextreme, $12 a pair) might not be a good move here, since at the competition there's going to be a lot of noise, and you might want to have decently tuned antennas not to pollute and be polluted. Haven't tested that theory though.

Lastly, to look at the video feed, the cheapest if you start from scratch (imagine you only own a computer, nothing else) is without a doubt a USB video adapter. However if you have TV (even an old thing collected on the side of the road) it's basically free - as long as you dont want to travel with it.

byi
01-13-2014, 11:06 AM
Ok. Thanks for the detailed info so quickly. I'm surprised that 100mW is enough. I was going to go with a pretty cheap 200mW but I think I'll go for 100mW if that is viable.

Xevel
01-13-2014, 12:46 PM
Well, in isolation it's completely viable. But that's not really relevant, is it? :/
I guess the way frequency allocation is done, the receivers available, the location, and the power and fidelity of the rest of the setups will determine if it was a good choice...

byi
01-13-2014, 12:52 PM
Hmmm... I can't find many 100mW transmitters and they generally are close in price to the 200mW I was thinking of getting from hobbyking, so I guess I will stick with that to be safe. This is all low enough power to avoid regulations anyway, right? I couldn't find anything legislation that would be a problem although my research probably wasn't too deep.

jwatte
01-13-2014, 01:40 PM
I've got the cheap HobbyKing 5.8 GHz 200 mW set-up, with the cheap HobbyKing pinhole camera. It works well enough for me (even at "only" 480 lines.)
I seem to recall that many mechs would reduce resolution a lot at Robogames to get higher frame rate and lower lag.

In the best of worlds, I'd have one camera with a 360 degree ball (pointing up) for situational awareness, and another one with narrow FOV for aiming and walking-ahead.
Also, sideways situational awareness is challenging; easy to scrape the walls of things you don't quite see on the side.

byi
01-13-2014, 05:36 PM
If I end up with some room in my budget I might get one of these:
http://www.hobbyking.com/hobbyking/store/__29651__Hobbyking_3_Channel_FPV_Video_Switcher.ht ml
G (http://www.hobbyking.com/hobbyking/store/__29651__Hobbyking_3_Channel_FPV_Video_Switcher.ht ml)et a couple cheap cameras and your situational issues are solved.

jwatte
01-13-2014, 08:44 PM
$5.50 is not bad. I could build my own, too -- it's pretty simple for analog video, and I already have the remote commands going to a microprocessor on-board.

Xevel
01-14-2014, 12:13 AM
If I end up with some room in my budget I might get one of these:
http://www.hobbyking.com/hobbyking/store/__29651__Hobbyking_3_Channel_FPV_Video_Switcher.ht ml
G (http://www.hobbyking.com/hobbyking/store/__29651__Hobbyking_3_Channel_FPV_Video_Switcher.ht ml)et a couple cheap cameras and your situational issues are solved.

Personally, I'm making my own, with 4 or 7 inputs. Components are more expensive than that though.
3 fisheye at 120° plus a couple other strategically placed cams with various FOV. Like a zoomed one on the barrel of the gun, a general purpose one front and back...

ArduTank
01-14-2014, 05:46 AM
Phew. You guys are loading up with cameras, and I'm just sticking to 1 camera at 640x480.

jwatte
01-14-2014, 10:48 AM
I'm just sticking to 1 camera at 640x480.

To be fair, that's what I currently have, too, and I'm only considering (haven't decided) a second, perhaps.

ArduTank
01-14-2014, 03:08 PM
Lol. I'm just happy with 640x480 because I'm used to crappy video with my internet connection and my previous computer's performance(lessness).

tician
01-14-2014, 03:54 PM
Lol. I'm just happy with 640x480 because I'm used to crappy video with my internet connection and my previous computer's performance(lessness).
Would this be as bad as having to watching netflix in a window less than an inch square (~150x120 pixels) because of silverlight on linux+wine? Amazing how much information one's brain can extract from such a small image as long as it is not too grainy.


Took several minutes with a dremel and high speed cutter bit, but got the omni-lens out of its iphone frame and ready to attach to the RPi camera whenever I make a proper mounting assembly. Only just realized that the inner surface of the lens assembly is actually threaded, so I should have been able to just unscrew it... guess it was just a lot more snug than I expected.


5275

ArduTank
01-14-2014, 03:58 PM
I'm used to only 360p or 240p video, which is why 640x480 looks good to me.

Xevel
01-16-2014, 08:02 AM
Just a quick follow up on my rant the other day:

I've tested the SpiroNet v2 antennas, just from looking at the output I don't see a sizable difference with the $12 DX ones.
Two things that are notably better though with the spiroNet v2: the transmit element is protected from damage (can be useful in a mech!), and the coax cable is a little longer and semi-rigid, so you can shape it.

Secondly, the Fatshark CCD killer 600TVL. I am in awe: it gives a crystal clear image in good ligting conditions, and when the conditions become worse (bright spots or low light), it still does very well.
With white lights, when the other CMOS show a white spot surrounded by darkness, this one shows a white spot with the rest of the picture being mostly readable. Even parts that are in the shadows. However if you have 50% of the FOV that is very luminous and 50% that is dark, one will win inevitably, living the other part unreadable (white or black). But single spots do not kill the whole image, that's for sure.
Whith generally dark conditions, the picture becomes very grainy but it still quite understandable: no black corners, and the colors are still good.
I'll sho that in a little more in-depth writup sometimes, with pics.



EDIT: the cam can be set to output PAL or NTSC. I just played a little bit with the jumper, just for the fun, and it appears that the result is vastly different in terms of quality >_<
First tests suggest that PAL sucks pretty hard compared to NTSC, at least on this cam... I'll get more in depth in the writeup, but it makes me regret choosing PAL for all my other cams :(

jwatte
01-16-2014, 10:35 AM
it makes me regret choosing PAL for all my other cams

Where's your national pride? Why no SECAM?

Xevel
01-16-2014, 11:36 AM
National pride is a poor substitute for image quality :p

ArduTank
01-16-2014, 11:43 AM
Why no ATSC??? Lol

jwatte
01-16-2014, 03:57 PM
Why no ATSC

That's actually an excellent question! I'd love for these cameras to support a low-latency digital format.

Unfortunately, the FPV electronics/kits haven't gotten to that point yet. And, evenso, I seem to recall that ATSC allows bidirectional predictive frames, which cause significant latency, so at a minimum, a real-time system would have to turn off that on the sending side.

Japan got an analog-based HD format a long time ago, IIRC, and that might be the next "small" step forward for the FPV cameras. It also seems as if some of them already can send more-or-fewer lines of video per frame than the particular TV standard requires, so there might already be some movement towards that. For a modern monitor, it's not hard to "pick up on" a different number of lines per scanline and display the appropriate image; the difference between NTSC and PAL (and SECAM) is more in how the color information is encoded, where you can't just "go with the flow."

ArduTank
01-16-2014, 04:10 PM
Mainly asking the ATSC question becuase of the higher supported resolution :)

jwatte
01-16-2014, 06:24 PM
ATSC is a digital compression based format. All the FPV systems are analog-based right now. Thus, it's likely easier to take a step to a MUSE/Hi-Vision type system, than all the way to ATSC.

Personally, I have also put a HD webcam onto a Raspberry Pi, and used WiFi to send each frame MJPEG compressed. Very low latency, very high resolution, but very dependent on a high-quality WiFi link. Thus, I'm now looking at analog systems as less dependent on the particular radio environment.

ArduTank
01-16-2014, 07:57 PM
The Raspberry Pi actually brings up a good question:

How much bandwidth does the router for MW have?????

jwatte
01-16-2014, 11:33 PM
The wireless access point for MW gives each contestant their own 802.11g channel. In ideal conditions, that's 54 Mbit/s air rate.
MW has never had anywhere close to ideal conditions, though -- one tenth of that might be a generous estimate of actual rates at the old venue.
We know nothing yet about the network and interference at the new venue.
The router doesn't matter, because it's not actually interconnected to the greater Internet.
(At least, that's what I saw when I took some gear there to try it out.)

Thorbear.H
01-25-2014, 12:22 PM
have anyone tried any of these products? seems to have good reviews.

http://www.hobbyking.com/hobbyking/store/__22394__Boscam_5_8G_500mW_8_Channel_AV_Transmitte r_FPV.html

http://www.hobbyking.com/hobbyking/store/__35055__Boscam_5_8GHz_Diversity_Receiver_7_0_Inch _TFT_LCD_Monitor_for_FPV_800x480_LED_Backlight.htm l

http://www.hobbyking.com/hobbyking/store/__39844__Boscam_Cobra_HD_FPV_camera_with_Integrate d_Video_Recorder_1080P.html

jwatte
01-25-2014, 01:37 PM
I haven't tried those particular products, but I have the following observations:
The camera claims to be HD, but the receiver/display you link is only 480 lines (so, SD.)
Then, the "AV out" from the camera is not specified whether it's HD or SD format, only the recording and picture function is specified as HD. Even the manual says nothing about the format of the AV out signal.
The transmitter is strong enough that I think you need an amateur radio license to use it (but check your particular locale and rules.)

Deimos
01-27-2014, 05:10 PM
I'm about ready to order my 5.8GHz gear, and I'd appreciate a second opinion on my parts:

FatShark 600TVL CMOS Camera (http://www.getfpv.com/fat-shark-600tvl-cmos-cam.html):
Xevel seemed pretty impressed with this one:

Secondly, the Fatshark CCD killer 600TVL. I am in awe: it gives a crystal clear image in good ligting conditions, and when the conditions become worse (bright spots or low light), it still does very well.
In addition, it has 100° FOV as well as overall good specs/reviews.

FatShark 5G8 250mW A/V Transmitter (http://www.getfpv.com/fat-shark-5-8ghz-250mw-a-v-transmitter.html):
Tybs said the channel group he was going to use will be compatible with FatShark transmitters, so I figured it would be best to get one of those. 250mW because they have it in stock on the same site, and it seems there is very little difference in performance based on transmitter power at close range.

Uno 5.8GHz NexWave A/V Receiver v2 (http://www.getfpv.com/5-8ghz-uno-a-v-receiver.html):
Xevel seemed to have success with this one, and I don't particularly care about audio so I doubt I will have to make any modifications.

Circularly Polorized CloverLeaf Antenna (http://madlabindustries.com/shop/fpv-gear/cloverleaf-antenna-kit/):
Because multipath distortion is bad. I'm also pretty sure these are the exact ones Tybs had at RG.


I've done a lot of reading, and I'm pretty sure all parts are good quality and compatible with each other, but someone else might catch something I missed!

Xevel
01-28-2014, 01:03 AM
The TX you link to seems to be the updated version of the one I have.
Like always, I started stuff and did not finish it. I got some new project for work in the meantime (gotta pay for my robot addiction!), and I did not post about the cameras...
Here is at least two little cap of the picture that I get with the FatShark 600TVL camera, one with the jumper on (should be NTSC) and the other with the jumper off (should be PAL).

jwatte
01-28-2014, 10:32 AM
Wow, that PAL looks like crap. I'm surprised!

ArduTank
01-28-2014, 10:37 AM
Lol. PAL does look like crap. Then again, both look like crap somehow compared to the 640x480 my webcam puts out. :confused:

Xevel
01-28-2014, 12:02 PM
Yeah, this surprised me too, all the more when you know that PAL is supposed to have a better "resolution" (625 lines instead of 525).
It's taken with the camera very still so there is no influence of the higher framerate of the NTSC.
<jk> I'm sure they made a mistake in the user manual and the crappy one is NTSC >_< </jk>

Xevel
01-28-2014, 12:13 PM
HAHA!
The user manual (http://www.fatshark.com/uploads/pdf/1745-1.pdf) says "cap on = PAL" and the product page (http://www.fatshark.com/product/1745.html) says cap on = NTSC.
I would bet that the user manual is the right one :p
The crappy one is the one without the cap. Take that NTSC!


EDIT : My oscilloscope agrees : with the jumper on, the field frequency is around 50Hz (so since an image necessitates two fields, the frame rate is 25 Hz) so it's PAL. Without the jumper, the field frequency is closer to 60Hz, so it's NTSC. This is measured directly by looking a t the waveforms at the output of the camera.
Those damn smart applications that visualize the feed (including VLC) tend to abstract that completely and report what I suspect is a default value based on your locale, instead of the actual frame rate.

EDIT 2: just for the record, I emailed Fatshark, I was right with the jumper putting the cam in PAL, they know the problem and someone (their IT guy?) will fix it when he'll get back from holidays.

Thorbear.H
01-28-2014, 02:47 PM
intresting. i have also found another, promising alterative for camera. the mobius action cam. here is provided an video, and a thread containing lots of useful information:

http://www.youtube.com/watch?v=yEJJ3okZ200

http://www.rcgroups.com/forums/showthread.php?t=1904559

i am impressed with the picture quality for the price, compares to gopro, but smaller unit.
as i am most interested in good recordings, and do not care about the resulotion for the reciever screen, i thing i will buy this:

http://hobbyking.com/hobbyking/store/__15295__Boscam_5_8Ghz_200mw_FPV_Wireless_AV_Tx_Rx _Set.html

and this: http://www.hobbyking.com/hobbyking/store/__28907__Fieldview_777_TFT_LCD_Monitor_for_FPV_800 x480_LED_Backlight_7_0_Inch_.html

i think i also will go with the mobius cam i am also thinking about moving the camera itself away from the rest of the electronic, by extending the ribbon cable, maybe using such a cable instead of the original one: http://www.ebay.com/itm/26PIN-RIBBON-CABLE-260MM-1-823-280-11-SONY-OEM-PART-/261363905232?pt=US_Audio_Cables_Adapters&hash=item3cda80b2d0

i will report back when my hexapod is up and running with the cameras, the screen is mackorder, so it may take a while.

Deimos
01-28-2014, 07:32 PM
That TX/RX kit uses a different channel group than the one Tybs said he would use at the event. I don't know if that will be a problem but at the very least you won't be able to use any RX that Tybs provides at the event.

Edit:
That is, assuming you intend to go to said event.

byi
02-01-2014, 12:40 AM
Hey guys. So, I am currently looking for parts, and I just want to run this past you to make sure I am not missing any compatibility issues or other factors. I am sort of wondering why this Tx/Rx set is so low priced relative to other sets of similar output power. I have a fairly constrained budget for this build, so I am trying to cut corners where possible without losing too much performance. Thanks for the help.

http://www.hobbyking.com/hobbyking/store/uh_viewitem.asp?idproduct=15295&buddycode=D3A450E3-F9FD-43C9-A5CC-66C8742ECD6E

http://www.hobbyking.com/hobbyking/store/__13434__1_3_inch_SONY_CCD_Video_Camera_NTSC_.html

jwatte
02-01-2014, 04:17 PM
I am sort of wondering why this Tx/Rx set is so low priced relative to other sets of similar output power.

Probably because the manufacturer cut corners? Like with anything else that is cheap, you may end up with a very good value for your money, but it's just as likely that you get no more than you pay for. (And, with anything else that is expensive, you either end up with very poor value for money, or you get what you pay for :-)
The trick is telling them apart, and you can't do that without actual empirical data...

Btw, that is the exact TX/RX set I have. It works, but the picture starts cutting out about 60 feet away through about two residential walls. Good enough for Mech Warfare.

byi
02-01-2014, 04:51 PM
If it's good enough for you, then I guess its good enough for me. Thanks.

Thorbear.H
02-02-2014, 06:53 AM
i am living across the pond, so i can't attend to the event, so i think the transmitter will be good for me.

Deimos
02-14-2014, 01:55 PM
I just did a quick test of my camera system, (details here (http://forums.trossenrobotics.com/showthread.php?5909-Let-s-talk-5.8ghz-FPV-camera-setups&p=62351#post62351)) and I'm really happy with it. The only thing that's missing is the circularly polarized antennas, which have yet to arrive.

The video is really smooth, clear, and low latency. The FOV didn't feel too bad at all (need to do more testing), and the dropped frames (presumably because of the rubber duck antennas) weren't very common, and didn't compromise my vision at all.

I'll write up a more detailed review when my antennas get here.

giantflaw
02-17-2014, 01:52 PM
What are the prefered frequencies at this time? I think channel group #4 is: 5740, 5760, 5780, 5800, 5820, 5840, 5860. Is that correct?

Deimos
02-17-2014, 02:32 PM
Those are the frequencies that Tybs said he will be using. So probably a good choice. (See here (http://forums.trossenrobotics.com/showthread.php?5909-Let-s-talk-5.8ghz-FPV-camera-setups&p=58481#post58481), and here (http://www.fatshark.com/uploads/pdf/1722-2.pdf))

Deimos
02-21-2014, 02:23 PM
I did a quick latency test with the following system:
FatShark "CCD Killer" 600 TVL CMOS camera
FatShark 250mW TX
ImmersionRC Uno5800v2 RX
Rubber Duck Antennas (Circularly polarized antennas still aren't here :/)
Misumi UVC video grabber
Youtube webcam recorder (Still haven't gotten around to finishing my control software)

Testing setup is as follows:
-Point FatShark cam at clock with milliseconds.
-Place FatShark cam display next to clock (so both clocks are next to each other)
-Point other camera so that both clocks are visible
-Put said camera in burst mode and take a bunch of pictures
-Find difference between clock values

I found the latency to be 190 ± 20ms. Not too shabby (although a little inconsistent :confused:). I suspect I could cut a little bit out of that number if I didn't use the youtube viewer.

Unfortunately I don't really know how I would determine how much latency is introduced by the video grabber, I don't have a "0" latency display to compare it to (CRT).

I'll test it again when I have my control software going. I will also post a video recorded by the FatShark Cam sometime soon.