Bad Singal due to Standard Rubber Duckies?

[John7845]

Hi All,

Having a bit of a frustrating problem with my new FPV set up, I think it might be down the
Stock Rubber Duckies.

My Set up Is below;

UNO5800V2 ImmersionRC Receiver-Powered by a 12V DC supply.
5.8GhZ ImmersionRC 600mw
600TVL 2.8mm CCD Camera
Standard Monitor


Basically I was doing a bench test this evening, however I can not get any picture.....

If I twist/turn VTX I will get a black screen rather than blue, and the occasional snow if I hold it
in a certain position...perhaps a bit of white noise if I am lucky.

I am powering the VTX at the moment with the only battery I have that will fit...a 350MaH 8.4V NiMH......is this to underpowered to give a good enough signal?? VTX specifies a minimum of 7V, and this was giving
out about 8V on my tester....I plan to use my on board battery when flying of course.

My other thoughts were the video (or what I could get in terms of snow and a little noise) looked
a bit like bad polarization....I was using the bad Rubber Ducky stock types when testing...could these
be so bad to not give me a picture at all?...I am hoping to get some Skews soon for it. ;D

My Final slight confusion was to frequency...I have it set to Channel 7 on my VTX, which is 5860MhZ,
however on my monitor I would only get the odd bit of snow when on channel 6, channel 7 on my VRX
gave me nothing?


I hope it is a problem with under power or the Stock Rubber Duckies...I am trying to work
out how to power the VTX for during flight currently, and hopefully ordering some Skews soon.

Thanks all so much...

  John.

[rob.thomson]

Hello,

Channels as displayed on various devices seldom in my experience match up - so dont take to much notice of that.

You really need to ditch the rubber ducks.  Get some decent clovers.   Ask flyn or bignose for some (on this forum)

They will make everything better :-)

[John7845]

is your cam 12v or 5v, if its 12v then your not giving it enough power. The standard rubber Duckies antennas are more than good enough, ive used them to fly with out to 1.5km so dont go spending on clovers or skews until you have the problem solved.

try power the vtx from a 3s battery.

are you sure you have it wired up correctly.

try all channels.

That's a very good point.

I agree the rubber duckies should give me something, and everything is wired up correctly....

however the camera is infact rated at 12V DC, and so perhaps you are right in saying I am not giving
it enough power!

I will hook up a 3S to it after making an adaptor, and let you know If I get anything...looks like the obvious problem though!

Thanks so much...lets hope it works! ;D

John.

[Coyote]

Rubber ducks at this point will not be the cause. Even with no antennas on ( Do not for the love of god try that ) you would still get a full clear picture.

Something else is wrong ............

Wrong pin order on your camera
Wrong voltage going to your camera
Vtx and camera not sharing the same earth
Camera lens still on .............. Yes it has happened before :)

8.4v is enough for the Vtx, it works at full power down to 7v no problem. 350ma is not going to get you very much use, the Vtx and the camera will eat that within one hour of it being fully charged

[g4uvz]

Looks like you have the answer...If you get a 'quiet' output from the sound on your monitor ..then you are tuned to the correct channel ..you are just missing the video signal ..12 volt cameras normally need at least 9 volts to come alive

[FPVSteve]

What I found was (to my horror!) that if you run the voltage too low your camera will first start to white out :o then .. nothing. Double :o

I'd say Hase2 is spot on ... try a 12V battery :)

[Coyote]

WDR`s will work down to 7.4v still and then degrade rapidly, so even on 2S he should still have a picture, if 8v is showing then it should still work.

[John7845]

Wow, lots of posts! :D

I believe everything else is fine, wiring, earth, channel etc an lens cap off! ;))

The only thing I questioned was I was on Channel 7 on VTX, but I'd only get a response from monitor
from channel 6 or 1 on my VRX, not Channel 7??!

Anyway, everything else is fine I'm pretty certain, I'm re-soldering all connections tomorrow to make a neater
job for eventual mounting, so I will test my connections to double check.

To me I think the most likely problem is not enough power to camera, I was using a very low power
battery that was draining quick....I expect it has just under 8V tops....and the camera is rated at 12V DC.

When I re-solder connections tomorrow night I will make an adapter for a 11.1V 3 Cell 1400MaH Pack I have lying around...and hopefully the camera should come to life....that's the plan anyway!

The only other odd thing in my mind that could cause anything would be
that weird channel thing going on, yet I still had a connection though....someone
did mention above that this is a common thing with slight overlapping channels on VTX's and VRX's

Thank you all so much for the help and contributions.
I will get to it tomorrow night and hopefully come back to here with some good news!

All the best,


John.

[FPVSteve]

My old camera used to die at 9.1V ... to me if it's a 12V camera and he's getting a signal but no picture when using 8.4V battery, it suggests the VTX is powered but the camera can't send a picture so I'd just do the easy thing and try a proper 12V battery...

[Coyote]

Some WDR`s come with a 4 pin socket, some 5. Your actual camera wire will have three, red black and yellow. If the order is wrong on the cable it won`t work, neither will it work if you have the 3 pin plug plugged into the wrong place. Make sure the pins match the pins on the OSD cable, IE red goes to red in the same place. You can also use the OSD cable to double check your 3 pin plug colour order

[John7845]

Thanks both,

My pin order is correct, including 12V in, video and ground-identical to the OSD lead.

I will try what I put above tomorrow and hopefully will get some results! :D :D

All the best,

Thanks for all your help,

John.

[John7845]

Right....Got a bit of a problem!

Went to charge up this spare 11.1V 3S 1400MaH lipo that I am planning to try and power
up my VTX+Camera with.....however it will not charge.

This battery has been left a long time and now must have discharged a lot,
I've had this problem with one other battery that I left in a model by accident,

When I go to charge on my mystery charger as I hold down 'start' I get an alarm and
'Low Voltage' error notification..it then refuses to charge.

Any Ideas of anything I can do to try and get the Voltage up in this battery enough to get
rid of the error and start charging it?........its the only spare battery I have left to try and power
it ;//

Everything else on hold now....

[Jake Bullit]

Set it to nicd charge for a few minutes, just to get some juice in it  then go back to lipo charge.

DO NOT LEAVE IT UNATTENDED AT ANY TIME!

[John7845]

Thanks...Ill give it a go ;))

[John7845]

Nope nothing...Charged for about 4mins, then I get a 'battery full warning'....but still get
low voltage error upon lipo setting....looks like this battery is a gonner, along with my dodgy charger.

I think I'm going to have to get a new 11.1V Lipo for this VTX. Anyone recommend a higher voltage...
what would you use for a 600mw VTX and 12V Camera???

Thanks again,

John.