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Thread: Weird China RF triggers

  1. #1

    Default Weird China RF triggers

    The cheapo China RF triggers I have (bought one set and one extra receiver, then not happy with quality control, thus went to change for another brand new receiver) all exhibit WEIRD characters.

    BAH. I am going to stick to the higher end ones from now on. Wasted my cash

    1. It takes 1/40s!* for the signal to be sent from trigger to receiver at 20m** distance! This is weird ain't it? I never knew know that RF signals (433MHz) move so slowly. Or am I missing something here?
    2. The trigger is useless beyond 15m (Even at 15m missfire occurs roughly 20% of the time). At 20m it is pretty much a touch and go affair.


    *(You ask me how I know - well, at 1/60s I fire the camera shutter. I can see the flash fire, but in the final photo the flash is not seen. I.e. shutter closes before the flash fires!)[/B]
    **At closer ranges like 5m this is no longer a problem, and I can safely trigger up to 1/200s. But then, at 5m range I might as well use CLS i-TTL right? (Doesn't apply to studio strobes. For Canon E-TTL I am not too sure


    Image for your reference. 15m

  2. #2
    Moderator catchlights's Avatar
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    Default Re: Weird China RF triggers

    一分钱,一分货。
    Shoot to Live, Live to Shoot
    www.benjaminloo.com | iStock portfolio

  3. #3

    Default Re: Weird China RF triggers

    Quote Originally Posted by catchlights View Post
    一分钱,一分货。
    Distance wise, if the thing cannot work beyond 15m I will still accept it. But...


    It takes 1/40s!* for the signal to be sent from trigger to receiver at 20m** distance

    what kind of stupid nonsense is this? And is it physically possible anyway?!

  4. #4
    Moderator catchlights's Avatar
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    Default Re: Weird China RF triggers

    is your trigger pass the handphone test??
    Shoot to Live, Live to Shoot
    www.benjaminloo.com | iStock portfolio

  5. #5

    Default Re: Weird China RF triggers

    Quote Originally Posted by catchlights View Post
    is your trigger pass the handphone test??
    This one, strangely, pass the test.

  6. #6

    Default Re: Weird China RF triggers

    Quote Originally Posted by chanjyj View Post
    This one, strangely, pass the test.
    Forgot to mention though, that they did not pass the test of close proximity. Keep at least 40cm apart.

  7. #7
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    Default Re: Weird China RF triggers

    Quote Originally Posted by chanjyj View Post
    Distance wise, if the thing cannot work beyond 15m I will still accept it. But...


    It takes 1/40s!* for the signal to be sent from trigger to receiver at 20m** distance

    what kind of stupid nonsense is this? And is it physically possible anyway?!
    It doesn't take 1/40 s from transmitter to receiver. It may take the receiver 1/40 s to react to the signal. By evaluating the signal for a relatively long time, the receiver gains immunity against electrical noise and interfering signals.

  8. #8

    Default Re: Weird China RF triggers

    Quote Originally Posted by LittleWolf View Post
    It doesn't take 1/40 s from transmitter to receiver. It may take the receiver 1/40 s to react to the signal. By evaluating the signal for a relatively long time, the receiver gains immunity against electrical noise and interfering signals.

    What you say would make sense had the flash not fired at speeds of up to 1/200s at 10m. Why the sudden increase in reaction timing at 20m leaves me bemused.

  9. #9

    Default Re: Weird China RF triggers

    Thinking back... I did alot of testing (alot means I blinded the whole neighbourhood).

    the final part of my testing was at 20m. It may be possible that the 1/40s speed at 20m is due to a low battery. I'll get round to testing it sometime.

    Have been thinking of zhnging it and adding an antenna too

  10. #10

    Default Re: Weird China RF triggers

    Used a coiled piece of wire (5.5cm, should be ideal for the 433mhz frequency, engineers pls correct me if I am wrong )

    Works ok now (I no more energy left to walk to 20m again and test at this time of the night)

    Strangely, straight piece of wire is useless, wire wrapped round transmitter also useless... only this shape seems to be able to trigger reciever. Really weird. REALY WEIRD JUJU
    Last edited by chanjyj; 20th January 2008 at 12:39 PM.

  11. #11

    Default Re: Weird China RF triggers


  12. #12

    Default Re: Weird China RF triggers

    You use it to trigger SB-800?
    I am NOT a PROfessional photographer and photography is NOT my hobby

  13. #13

    Default Re: Weird China RF triggers

    Quote Originally Posted by Youhong View Post
    You use it to trigger SB-800?
    800, 600 also. Have not used on strobe yet.

  14. #14

    Default Re: Weird China RF triggers

    Disappointed. After adding the extra antenna, (despite theoretical increased range of 30m), range remains the same and the furthur you go, the slower the flash responds. By the time I reach 11m, shutter speed has to be approx 1/60s (which means I cannot overpower the sun) and that is, if the stupid receiver fires the flash at all. (I would say failure rate of 50%).

    Any engineer here who can advise me on the antenna? I really at a loss now. According to science, I have already done everything right.

    (It is not the transmitter or receiver problem. I have already went to change for a new set. Problems are identical)

  15. #15
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    Default Re: Weird China RF triggers

    search the strobist think there is a mod for it. I did it too does improve the signal but I switch to something which is never fail and longer distance.

  16. #16

    Default Re: Weird China RF triggers

    Quote Originally Posted by longkangman View Post
    search the strobist think there is a mod for it. I did it too does improve the signal but I switch to something which is never fail and longer distance.
    I saw those mods. I use them as a basis for my own mod but realised that their antennas all don't work with mine although we all using the same chipboard.

    I had to make a curly shape for the darn thing to work (and must circle around 2 times somemore).

  17. #17
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    Default Re: Weird China RF triggers

    mine does improved a lot, but I switch another america brand but make in PRC.

  18. #18

    Default Re: Weird China RF triggers

    Quote Originally Posted by longkangman View Post
    mine does improved a lot, but I switch another america brand but make in PRC.
    =.= Why my receiver like so suay one.

    What is the shape of your antenna?

  19. #19
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    Default Re: Weird China RF triggers

    Quote Originally Posted by chanjyj View Post
    =.= Why my receiver like so suay one.

    What is the shape of your antenna?
    I just let it come out of the casing, you can have mine to test it. After the mod wow it is shoik but still can't beat the real one.

  20. #20

    Default Re: Weird China RF triggers

    Quote Originally Posted by longkangman View Post
    I just let it come out of the casing, you can have mine to test it. After the mod wow it is shoik but still can't beat the real one.
    I just modded another one. Fed up. This time I just took one antenna and stick on the stupid transmitter. (when I shoot I extend the transmitter antenna up by 3 times).

    Look like some stupid alien

    Your real one is what? Pocket Wizard, Bowens or Elinchrom?

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