DIY pH meter

Discussion in 'Anything DIY Related' started by viper357, 14 Jul 2009.

  1. viper357

    viper357 Admin MASA Contributor

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  3. Warr7207

    Warr7207

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    Iighty, Leslie and the other DIY guru's ???
     
  4. AndrévN

    AndrévN

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    Gonna send ighty one i found tonight where you dont need adding and subtracting :whistling:
     
  5. Kavir

    Kavir

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    Looks easy but to complicated wit all the numbers
     
  6. riyadhessa

    riyadhessa

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    Nah im no good at this...
     
  7. Reef Maniac

    Reef Maniac MASA Contributor

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    I seriously doubt if it will work properly in a marine tank. Our tanks all have stray voltages induced by pumps, fluorescent and MH lights and various other electrical devices, and these stray voltages will seriously affect the "calibration" of the instrument.

    Hennie
     
  8. Stressed Eric

    Stressed Eric

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    The pH bulb is the expensive part, trust me ! and when you put a moving coil meter with it's components or a multimeter for the readout, sigh, nah . . . But it's a good read and gives a nice explanation of how the bulb works. Thanks dude :)
     
  9. lIghty

    lIghty

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    Here one I designed after some research, very basic yet effective. I've tested the prototype on bread board (which was unshielded) and worked fine with 8x 54w T5 60mm above the water. Haven't tested with MHs.

    [​IMG]

    PS, there is a cap ommited on the probe input.
     
  10. brettb2020

    brettb2020

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    it will work perfectly guys. this actually how a proper one you buy in the shop works except that it has a built in PIC that is programed with the probes mv per pH value and a few equations so it works it out for you and displays it.
     
  11. lIghty

    lIghty

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    Assuming you are talking about the one Viper posted, it will work but is a bit susceptable to noise. and you would still need to get your calculator out to work out the pH, whereas my schematic is more "stable" and the output is equavilent to the pH, eg. 8pH = 8 volts, 8.3pH = 8.3volts.
     
  12. Dohn

    Dohn MASA Contributor

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    so do you know how to build an sg meter
    Would be quite cool if we could get all these consolidated into one box with a multi switch and 2 probes to put your multi meter into. Could measure everything with a turn of a knob
     
  13. lIghty

    lIghty

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    Dohn. I have't looked into it, but will, I could imagine it could be quite tricky to get calibration spot on....
     
  14. Dohn

    Dohn MASA Contributor

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    ooooo, and a temp probe to.....
    Those are the three things i wish i could measure digitally.
     
  15. lIghty

    lIghty

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    Temp is one of the easiest to do.

    Dohn, do you think you have the skills to be able to etch a board? not all that hard, as there are some nice schematic around for temp controllers.
    Posted via Mobile Device
     
  16. Dohn

    Dohn MASA Contributor

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    I can get hold of those electronic kits and maybe use a circuit board from one of them with the components you suggest. I wonder if i can get titanium probes here
     
  17. AndrévN

    AndrévN

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    You get that TDS, ORP and CO2 controller i mailed. O and that aqua controller schematics yet. :wave2:
     
  18. lIghty

    lIghty

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    Buying other kits will work, but can't realy change then.

    See if you can get single side copper board (PC Board) and ferric oxide (for ecthing) if you can, let me know! really not that hard, I'll get you thru it!
     
  19. AndrévN

    AndrévN

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    The one u sent me
     
  20. lIghty

    lIghty

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    I have received some, haven't open all yet, I'll let you know.;)
     
  21. AndrévN

    AndrévN

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    Theres some nice stuff in there bro youll see ;) AMAZING :1:
     
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