Throttle causing FPV feed to drop

[bhagerman]

First round at setting up a system for FPV flight. In home testing everything appeared to be working as expected, when I spun the throttle up (with no prop) the camera signal remained strong. However, with the prop attached the signal drop is basically instantaneous. Once I give it a little bit of power the screen cuts to static.

Parts List:
Battery: https://store.flitetest.com/lumenier-1000mah-3s-35c-lipo-battery-xt60/
Motor: https://store.flitetest.com/emax-motor-mt2204-kv2300/
ESC: https://store.flitetest.com/blheli-series-12amp-esc-xt-30/
Receiver: https://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=91061
Trans + Camera: https://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=81335
I'm also running the power through a filter: https://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=43725

At this point I'm a little stumped. I knew that the engine could cause some signal interference, which is why I went with the filter, but this doesn't appear to be interference. It seems like the power draw causes such a drop that the transmitter is no longer sending a signal, but if that's the case I'm not too sure what the solution would be. Is this an appropriate FPV setup, or am I missing a needed component?

Thanks

 

[PsyBorg]

Sounds like a major brown out. Im running them same motors on just 20c batteries and 12a esc's and have never had a brownout. My guess would be to ditch the filter for a few tests. I don't run one and have no problems on mine. Fat shark gear is proprietary stuff and does not like playing well with others going by what I read about it.

If that does not solve your problem take a few pics of your wiring and how its all set up so we can take a more in depth peek and see if we can find an answer.

 

[bhagerman]

Interesting, brown out would definitely fit the bill. I may have backed myself into a corner with this setup however, I'm not sure how to power the camera + receiver without the filter. The filter is setup to draw power from the LIPO balance plug, and that gets fed into a JST plug for the receiver. How is your camera power setup, one battery and a splitter or?

Appreciate the input.

 

[PsyBorg]

My matching VTX and camera came with a power cable that plugs right into the battery balance connector. If you pull power from there motors should never be a problem as they are after that tap point. I spliced my battery alarm into that cable as well and have no problems even after grabbing a dead batter yesterday and the quad floating down because the esc's went into low power mode. (kinda wondered why the battery alarm was acting funny. Thought it was just because it was a bit cold outside).

 

[bhagerman]

Good to know, seems like my equipment selection was poorly chosen. Since my VTX is powered with a JST plug what are my options, should I clip it and solder on a 3S balance plug?

 

[PsyBorg]

Not necessarily a poor choice. Your thoughts were sound. Like me being new maybe just not enough research before making the purchace of your gear.

There are several ways to do it. The FPV setup you have says it uses 7- 23 volts input to the VTX which in turn steps that down to 4-5 volts to power the camera. Since you are only testing the theory that the filter is causing the problem you could temporarily tack solder the VTX power leads to any available 12v pads on the power distribution board or at worst case directly to the battery input lead on the PDB. Or if you have a mated JST you could solder that to the PDB so you don't have to mess with the VTX current set up. Once you determine if that solves the problem or not then a more permanent connection can be worked out.

MAKE SURE you pay attention to polarity or that could easily tank the whole project and even be a possible fire hazard with a full charged battery.

 

[bhagerman]

Haha, yeah I always get stressed out about polarity, good tip. Really appreciate all the help so far, unfortunately I'm currently running a scratch build Mini-Arrow so there's no PDB on hand. I should have provided pictures but as it stands I have the 3S lipo running directly to my ESC and am using the balance plug to feed into the filter. I agree that the proprietary filter is probably the weak link here, just unsure how to get an alternate setup up and running.

 

[PsyBorg]

Well if you have a matching connector that will work off the balance port on the battery you could use that to connect to the JST plug on the VTX easily enough. Just use the negative (black) and the outer wire on the balance port to connect to the JST.

 

[Heavy313]

Might want to pose that question here: http://forum.flitetest.com/forumdisplay.php?15-FPV