Voltage problem

Discussion in 'Parts & Components' started by mozquito1, Apr 30, 2018.

  1. mozquito1

    mozquito1 Well-Known Member

    So my problem is I just bought a
    GEP vtx..... One of these
    Which runs 7-24v
    This is for a micro 130
    I also bought this
    Along with an BF omnibus f3+osd.
    The vtx on my other 130 is 5v.
    My problem is I need a step up from 5v to 7v+. So if I buy a regulator with adjustable voltage.. Where would I put it. I suppose I could run it off the main leads, but would this be OK.
    Also I use 1000uf 36v cap on my regular 4s setup. What can anybody recommend as the smallest cap that would be ok for a 450mah 3S.
    I got a bunch of em but they nearly bigger than the quad.
    Im only running these motors on a 15amp 4in1
    Could I get away with a 20v 600uf or somthing similar.
    Hoping the doc can chime in here.
  2. Jackson

    Jackson USA member at large

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  3. RENOV8R

    RENOV8R Well-Known Member

    I'd just wire the vtx straight to the lipo instead of to the FC, that way you wouldn't need to step up the voltage. Don't know about the GEP vtx but most now advise that you power directly from the lipo as the have their own internal filtering. Then add this 470 uf cap and you should have good clean video. This would be basically the same setup as on my Jappy, and it has good picture
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  4. DrAbsurd

    DrAbsurd Well-Known Member

    As long as the voltage is higher than the total volts going into it from battery or source it wont explode. 4s is 16v so 20v on 3s should be fine. The uF is how much power is stored and can be pulled out. This is where my understanding gets vague, but it sounds like plenty. Actually the math ive run across seems to imply that in our application as long as its over a few hundred uF then it will work. I would hook up the positive and negative from the vtx straight to the battery leads going to Power Board and put the capacitor on the same leads. As long as its in line somewhere it will suck up those power spikes and keep the whole circuit cleaner. You can also use smaller capacitors on each esc lead but this can get crowded. Going bigger is ok but going to small can lead to bang. Capacitors will try to equalize with the battery and as long as the v ratting is higher than the battery output, its good to go.
    Last edited: Apr 30, 2018
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  5. mozquito1

    mozquito1 Well-Known Member

    Thanks guys, I normally go with what's on offer from a pdb or fcb. I don't like putting on the mains if I can help it, because of spikes. I have before but used an LC filter.
    But the ones I got ain't going anywhere near a 130. This is my 2nd build without a pdb & just making sure.
    Much appreciated. :cool:
  6. mozquito1

    mozquito1 Well-Known Member

    I was nearly gonna buy another Unify nano just because its 5v. But I haven't had a chance to test it out. Wettest spring on record here,windy as hell.
    it's nearly may & snow is forecast again this week. I'll fly in the wind but my pet h8 is getting my trainers wet.
    Get wellies you say, and look like a chump. o_O i only got one waterproof kwad & for a 130, it's a bit heavy with single esc's on it. As small as they are.
  7. Spork

    Spork There is no spoon

    :eek: Ouch.

    It's my new pet h8. My last three pairs. First week. Wet, Mud, Paint. :mad:
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  8. mozquito1

    mozquito1 Well-Known Member

    Painto_O that's just wrong. :D
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