Intermittent video signal loss

adamd

skunkworx hobbies
I am new to the amazing world of fpv and have fallen in love! Ever since watching David's sky walker x8 video I have been infatuated with this part of the hobby.

My problem-
Once the Aircraft gets in the air I start getting intermittent video signal. I will loose video for 1 to 2 seconds every 5 to 10 seconds. It always comes back but it leaves me flying like a stop motion video!! Not safe!! I always end up pulling the goggles off and just flying back (being a spotter for me is a full time job!).

Now with my amazing inexperience with this type of system I have narrowed it down to some possibilities.

1. My cable going to my gopro (hero first gen) when I move it I loose signal. Any tips for keeping that audio style cable (3.5 mm) from spinning in it port? I also have built a gimbal so it does a lot of moving.

2. Location of my tx is on top of my plane. It's just foam board I'd assume it can't cause to much of a wall for the signal?

3. Channel interference?

4.crappy cheep ebay clover leaf antennas?

5. System running off same power source as plane?

I have been plagued with so many problems trying fpv for the first time but I know it was my stubborn self not asking for help and rushing to get to the field so now im slowing down so I can have the best possible experience!
Can any of you fpv genies out there help a young man achieve his goal of flying fpv! And feel free to include any other tips to help me succeed thanks for the help!!!!

All You guys make this hobby what it should be..... FUN


Adam
 

xuzme720

Dedicated foam bender
Mentor
Might be a combination of things causing this for you. I would take it a step at a time and try to narrow down the culprits systematically. For instance, start by taking the motor out of the equation by placing the plane on the ground and walk away from it with the video goggles/monitor. Does the video act the same as it does when the motor is running? If it does, you can eliminate the motor. If not, then you'll need to filter or use a separate battery for the video.


Eliminate likely culprits first to troubleshoot and you should be able to track it down. I would start with the go pro cable before doing the motor test, since that is a known intermittent cause by itself. Is the cable bad or is it the port? Can the cable be secured to the GoPro to eliminate the loss of signal even if the gimbal is moving? That type of thing...
 

adamd

skunkworx hobbies
It goes black total loss Also I have no base station video. I run my receiver with a 2200mah 3s 8c battery and 2200 3s 25c battery to run the plane and fpv tx. I Used an elastic band to keep the plug from Turing in the port and it stopped "that" potential problem. I also tried spooling the motor at a distance to see if it it interrupted the signal and it did not. I tried the giggle and shaking the plane while poking at wires method with no video loss. But my helper notice when I moved the video would start to flicker at any distance over 100' and even worse when the clover leaf was pointed away from the receiver ( not directly behind or in the "donut hole")
 

xuzme720

Dedicated foam bender
Mentor
Unless you've got serious interference in your area, you should be able to get beyond 100'.

How sure are you that you are truly on the same channel on both units? I haven't run into it but read that someone was off on the channels and would still get video but horrible range...
Maybe try a different channel and see if that helps any...it has for some in the past.
 

adamd

skunkworx hobbies
My 5.8 can pick up some signals when the rx and tx are on different channels but I have checked and double checked the dip switches to make sure they are both the same. I just found my old antennas that came with the stock unit, im going to see if my cheep ebay cda's are my problem. I dont get static just black screen. I have also tried different channels with no luck. Would it be worth the investment to pick up a signal scanner to see if its interference?
 

steadly1

Member
i would check your wiring, make sure there is not a loose connector or a break in the wire some ware (the wire can break inside the insulation) . power everything up jiggle every connector and see if you can simulate the problem. check your antenna connections to.

i don't think it would be interference, you should see something, bars or static, not just black.

also check your vtx or vtx regulater is not overheatig. expesualy if you have a linear regulator powering your video transmitter,
 

adamd

skunkworx hobbies
i power my vtx directly off a 3c (same as my flight battery) it does tend to get warm but its rated to 15v. i see all the warnings and horror stories about plugging in a tx without an antenna but what would be the consequence?
 

Tritium

Amateur Extra Class K5TWM
i power my vtx directly off a 3c (same as my flight battery) it does tend to get warm but its rated to 15v. i see all the warnings and horror stories about plugging in a tx without an antenna but what would be the consequence?

ALL the transmitter power would be dissipated as heat in the transmitter output section which would BURN it OUT! Time for a new transmitter. ;)

Thurmond
 

adamd

skunkworx hobbies
ALL the transmitter power would be dissipated as heat in the transmitter output section which would BURN it OUT! Time for a new transmitter. ;)

Thurmond

I haven't powered it on without a antenna but I can't be sure that I haven't had continuity problem with my antenna, so i'm just ruling things out as I go. if it did what would be the result in picture quality or would picture be non-existent. I have read of people getting only 30m off the system post vtx frying. I'm going to do a range test today with the help of some friends to see if i get range, but limited connectivity to rule out antenna issues.
 

Tritium

Amateur Extra Class K5TWM
Picture could be non-existent or severely degraded if the transmitter output section is damaged. 5.8 test gear is terribly expensive so a walking range check in an area with as low of a RF noise floor as possible would be best (read that as way out in the country not in a city park). There are more and more 5.8 WiFi routers in use so the high noise floor situation on that band is not likely to improve.

Thurmond
 

adamd

skunkworx hobbies
i live in the bush so not much noise, i get 20 to 30m range so its fair to say i fried it ahah any repairs possible or should i just get another?
 

Tritium

Amateur Extra Class K5TWM
Unless it is a 10mW unit then yes something is definitely wrong. What is the advertised power output? Probably cheaper to get another but no way to know if repairable or not unless in hand.

Thurmond
 

adamd

skunkworx hobbies
its a 200mW boscam. can only the transmitter burn out? or can the VRX burn out as well from being powered without an antenna. im assuming the VRX is just a sensing loop while the VTX actually is a load?