RC Model Reviews

Okay, sounds as if there's a diode in there which will account for the voltage drop. I guess they're just trying not to exceed the maximum voltage rating of the camera even with a fully-charged 3S lipo.

Seems that way Bruce.

Btw, I've just been watching the cricket through my FatShark goggles hooked up to the composite out on the TV... Mrs Sid had hysterics watching me and then I tripped over the dog.

I can see these things need some practice, lol.

RCModelReviews wrote:Okay, sounds as if there's a diode in there which will account for the voltage drop. I guess they're just trying not to exceed the maximum voltage rating of the camera even with a fully-charged 3S lipo.

Well, I figured out how to wire it all together, but as I mentioned on your latest FPV video comments thread, I'm unimpressed with both the camera and the FatShark goggles.

The camera has awful resolution and although the replacement wide angle lens is certainly better, the distortion is distracting to say the least. Seems from further reading that the cameras prefer 9v, so maybe dropping the voltage even further may help. Whatever, I'll be interested to see how you go fooling around with the connections you mentioned on the video too.

As for the Fatsharks, well the quality is really el-cheapo for the money. For a start, my contrast and brightness switch crapped out after only a couple of uses. The switch seems to be faulty, or maybe the circuitry, as it does nothing sometimes and then reluctantly starts to work again for no obvious reason. Really pissed me off, that did.

As for the eyepieces...they are just rubbish and the plastic diopter inserts make things even worse, being too close to your eyes, so that one's eyelashes smear the lenses quickly.

I believe the newer Dominator* goggles use glass lenses, but I bet they are just simple magnifiers, instead of coated cemented doublets (let alone properly designed eye-pieces). I'm going to pull my Fatsharks apart and replace the optics with something much better, once I find out the size of the LCD panels and the focal length I need to image them properly. The image of the panels (if not the content) should be sharp as a tack, without any blue fringes or other rubbish, like I get now. Also with replacement eye-pieces I can set the magnification and thus the field of view to what I want.

* Edit: Useless for me anyway, because they don't have inter-pupil adjustment, which I must have.

Sid, contact Fatshark, they will fix your contrast switch under warranty.

My Fatsharks (base) have started to go randomly bright, they get brighter and brighter over 2-3 seconds until the screen is completely white then jump back to normal. Needless to say that is terrible so I contacted Fatshark. They are sending me out a replacement LCD driver board (after I paypal'd them a $25 deposit) so I can swap it myself and send the fault one back. My contrast switch has the same problem as yours. I mentioned that to them and they said they'd send out both boards for the same deposit.

My only concern is that if your switch has died too then how long will my replacement one last?

I loaned mine to a guy who had previously used FS Predators (25 deg FOV) and he said he much preferred the 46 deg FOV of the base goggles. I think that while $230 seems like a lot of money, it's actually really cheap for what you get.

Personally I'm still stoked just to be up and FPVing. I'm going to get a better camera as the $16 HK ones really are crappy, but crappy is infinitely better than nothing.

rogueqd wrote:Sid, contact Fatshark, they will fix your contrast switch under warranty.

Thanks mate, I'll contact FatShark and see how I go. Though as you say, it makes you wonder how long the new switch/board will last.

Have you had a go at dismantling your goggles yet? They seem to be glued together, although it may be some kind of clip arrangement.

As for the camera, well that was always just a cheap way of getting into FPV while learning, as I won't burst into tears if I crash and break it.

There must be a better one with something approaching standard PAL resolution that won't break the bank, so anything Bruce discovers on that front will be good to read about.

Btw, the Remzibi OSD works a treat, so at least something is as it should be.

Where do we get these $10 5.8ghz patch antennas you speak of?????

I've already designed a small arduino diversity circuit taking the RSSI values from the RX's and comparing them and then using a relay to switch between video sources. Will share when it's done.

What I've just been thinking about recently is how do I calculate the heading and angle from the horizon to point the antenna based on the plane's GPS position? I have a huge amount of space left on the arduino so might as well put it to good use having a directional patch antenna and a diversity controller!

chrisjunkie wrote:Where do we get these $10 5.8ghz patch antennas you speak of?????

Quite a few companies sell them now... I got mine from HiModel.com.

What I've just been thinking about recently is how do I calculate the heading and angle from the horizon to point the antenna based on the plane's GPS position? I have a huge amount of space left on the arduino so might as well put it to good use having a directional patch antenna and a diversity controller!

I'll explain the math when I do the tracking project. It's pretty simple trigonometry really.

Yeah my thinking is what I'll do is a diversity type tracker. Have three receivers like so:
1. Patch antenna pointing into the middle of an old sky satellite dish I managed to score
2. Patch antenna pointing straight at the model
3. Skew-planar or circular polarized antenna for around the back flying etc

These arduino's sure make things like this easy. Keen to see the cheapo 5.8ghz module thing too. Might have to etch my own PCB if it gets too complex

Bruce, anything you'd like for FPV reviewing? I'm about to do a HobbyKing order and am happy to add a few donated items to my order? I'm in Auckland so no biggie sending it down

Cheers
Chris

Hi Chris,

I'm waiting on my own order from HK so there's nothing I need from them right now (at least nothing I need that they have in stock )

Still waiting for some other bits from other Chinese suppliers but now that the Chinese New Year festivities have kicked in, I'm picking it'll be a long wait. Fortunately I don't need them to do the DIY backpack build video.

Sid Sideslip wrote:Have you had a go at dismantling your goggles yet? They seem to be glued together, although it may be some kind of clip arrangement.

Fatshark asked me to open them so I could send them the version numbers on the PCB's. Here's the instructions they sent. I'm not sure if following them will void your warranty, but it sounds like they understand that their customers have a decent amount of technical knowledge.

Code: Select all

Heres a short procedure on how to open:

(1)     Remove the strap from the goggle (goggle holder is C shaped so strap loop can slide out)

(2)     peal back the headset foam in the nose area
   (so that the foam doesnt rip in half when the top case is removed)

(3)     remove the 2 screws on the bottom

(4)     hold the headset in your RIGHT hand with the lens facing to the RIGHT

(5)     with your left hand, grab the top of the case and with your fingers,
   pry top case from the strap holder

(6)     the case will resist but dont worry ?its held in place by 3 snaps

(7)     you may hear a CRACK?again dont worry, its just the snap releasing

(8)     the center snap by the nose may break ?no problem its redundant


To exchange the LCD driver:
- note the direction the LCD tails insert into the connectors before removing
(they insert different face up - see attached photo)

- loosen Zif connector before removing

- remove LED backlight connector by pulling up from the connector, not the wire
(locking connector so pulling by the wire will break the wire).

- note the the LCD driver sits on a angle to fit inside the case

After following the instructions I found there are actually 2 center snaps, one on either side. I managed not to break either of them. Use a normal amount of firmness and caution and you'll be fine.