5.8 fpv system not working right

mavrik12

Member
So I have a 5.8GHz sky zone plug and play + quantum fpv goggles. I did have it working at first but I only got about 100ft to 150 ft of rang from it. From what I can tell that is really small. Now I cant get more than 50ft away and my signal keep cutting out randomly even if I'm not moving or powering the quad copter. I'm new to fpv on my 250 quad, I'm out of my depth here.
 

Cyberdactyl

Misfit Multirotor Monkey
Could be several things, but most likely I suspect a loose connection or cold solder connection somewhere. If it wasn't a "package" I would suggest you may have an opposite polarity issue of you were/are using spirals. Also, are you using monopoles at both ends?
 

Julez

WOT and going nowhere
Your first course of action should be to move up and down a few channels on your receiver, to make sure that you aren't on an adjacent channel.

Next, make sure that all of your antennas are screwed in fully, and make sure you don't power up the video transmitter without an antenna attached. Doing this will damage the transmitter.

Make sure that the antennas are pointing directly up. Cloverleaf/ Skew Planar Wheel antennas have a deadspot directly above them, and so you want to position them so that they are radiating to the sides. (Imagine having a donut, and the antenna goes in the middle of the donut. The donut is your radiation pattern. There are weak spots above and below the antenna, so you want to make sure you're not receiving in the antenna's weak spot.

Finally, try it in a different area. RF noise can be particularly high in one location, and virtually nonexistent in another. Testing your gear in a variety of locations gives you a good chance of finding a place where RF interference is minimal.
 

mavrik12

Member
I did make shur that the antenna are screwed in tight, and I have never powered up the transmitter or the receiver without the antenna attached. As far as interference goes, I experimented with different channels and used my 5.8/2.4 ghz analyzer and looked for the least busy channels. "I still need to try a different location though".
 

FlyingMonkey

Bought Another Trailer
Staff member
Admin
The battery could be dying. Range would reduce with the battery level.


Can you take a picture of your set up?
 

FlyingMonkey

Bought Another Trailer
Staff member
Admin
Another thing I'd suggest is likely wrong... did you crash or have any hard landings? Inside the plastic piece on your antennas, is the metal lobes. I bet the solder came loose on one of those.

Also those transmitters can be a bit sketchy. I have one that I never got any good range out of.
 

mavrik12

Member
This is my new placement of the antenna and I have a 90* bend on the way for it,
but it was strait up before I moved it.
20150728_172452.jpg 20150728_172506.jpg 20150728_172530.jpg 20150728_172536.jpg

Also sorry for the delayed response but Comcast decided to kill my internet for a day.
 

FlyingMonkey

Bought Another Trailer
Staff member
Admin
Did you power it up without an antenna on the transmitter on the quad?

If so, you may have killed the video transmitter. It needs an antenna on it, whenever it's plugged in.
 

Julez

WOT and going nowhere
Did you power it up without an antenna on the transmitter on the quad?

If so, you may have killed the video transmitter. It needs an antenna on it, whenever it's plugged in.

Fred, see his response to my post- he's never powered up the vtx without an antenna.

I did make shur that the antenna are screwed in tight, and I have never powered up the transmitter or the receiver without the antenna attached. As far as interference goes, I experimented with different channels and used my 5.8/2.4 ghz analyzer and looked for the least busy channels. "I still need to try a different location though".

At this point I'm going to lean towards what FlyingMonkey's saying about the overall quality of the vtx/vrx system. I would suggest removing your FPV gear from the quad and testing the distance solely with the video gear. Perhaps there's some funky kind of propagation going on because of the frame...
 

Julez

WOT and going nowhere
Also- even if you bought it as a kit, there's a possibility the antennas could be RP-SMA while the vtx/vrx connectors are SMA.
 

Snarls

Gravity Tester
Mentor
How are you orienting your antennas? From the looks of the pics the antenna on the RX is kinda diagonal across your face, and on the quad at the vTX the antenna is pointing horizontally. The way these antennas work, there is a hole in the signal along the axis of the antennas wire. If the antenna is horizontal and pointed straight at you (as if your flying away from yourself) the reception is going to be bad. If this is not true, and you use a 90 degree adapter on the vTX and vertically position the one on the RX, then you might have to contact Hobbyking about a defective product.
 

mavrik12

Member
So I tested the range by plugin the rx and tx up to separate battery setting the rx and camera on my car and waling down a strait street until it gave out, I can keep video signal for about 100 ft, but my tx seems to loos connection for 30sec to 2min than randomly regain connection"this happens at all ranges".
 

mavrik12

Member
How are you orienting your antennas? From the looks of the pics the antenna on the RX is kinda diagonal across your face, and on the quad at the vTX the antenna is pointing horizontally. The way these antennas work, there is a hole in the signal along the axis of the antennas wire. If the antenna is horizontal and pointed straight at you (as if your flying away from yourself) the reception is going to be bad. If this is not true, and you use a 90 degree adapter on the vTX and vertically position the one on the RX, then you might have to contact Hobbyking about a defective product.
I tested with them both vertical this is my new placement, and I have a 90* bend coming to keep it vertical.
 

mavrik12

Member
Ok so I went through and check all the soldering to make shur it was not any bad connections, and I could no see any thing wrong.
I'm still losing connection withing 5ft, and at randoms moments, and it will randomly come back anywhere from 5sec to 5min. Now I'm thinking of buying a new set of antennas, and a video transmitter. Any suggestions on what I could get I was thinking of:

Video TX:
http://www.amazon.com/Boscam-Wirele...016&sr=8-22&keywords=5.8ghz+video+transmitter
Antenas:
http://www.amazon.com/Anbee®-5-8Ghz...qid=1438628530&sr=8-1&keywords=5.8ghz+antenna

Tell me if this is the next corse of action Thanks.
 

RandomChaos

New member
Check your camera. I have a SC2000 in a case like that, and one of the crystal leads broke. Video would go in and out as the broken lead would touch then not touch. Some soldering, and hot glue blob to hold it in place, all is good again.
 

mavrik12

Member
Check your camera. I have a SC2000 in a case like that, and one of the crystal leads broke. Video would go in and out as the broken lead would touch then not touch. Some soldering, and hot glue blob to hold it in place, all is good again.

Ill make shur to check that when I get home today, and I'll post on it.
 

mavrik12

Member
So I checked all the wiring and there is no loose wires, or soldering coming off, How can I tell if my transmitter is dead?
 

mavrik12

Member
So I bot a 90 Degree coaxial bend for my quad's fpv antenna, and when I went to range test the fpv system I'm now getting .4-.5 of a mile around 1km, I tried without the bend and got the same problems before. I don't know what was going wrong but it seams to be gone now.

Thanks for all the advice.
 

RandomChaos

New member
Is it possible you were connecting SMA to RP-SMA, and the right angle is an adapter that changes it from SMA to RP-SMA?