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How to make a pH meter at home? 


      _cc781905-5cde-3194-bb3b-136bad5cf58 of your orchids water and solutions you can measure the pH of your orchids be the point between the success and failure of your cultivation. This is because fertilizers, pesticides, the absorption of plants depends a lot on the pH. There is an optimal pH for each product to have its best effect. 

      _cc781905-5cde-3194-bb3b-136bad5cf58 you can normally use an electronic pH meter make one at home. 



Measuring pH with Red Cabbage (pH 1 to 12)



- Red cabbage leaves; 

- Pan; 

- Strainer/sieve; 


How to do it? 


1. Take the red cabbage leaves and cut them into very small slices , put them to cook with an amount of water equal to that of chopped leaves. Let it boil for 15 minutes and let it cool down. Now, use the sieve and try to extract all the remaining water into a clean container. To increase the shelf life, add a little alcohol and keep in the refrigerator.


2. To measure the pH of any substance, just add a few drops of Red Cabbage Extract to about 5 ml of the solution you want to measure. From the color the mixture has, you will know if it is basic or acidic. To better visualize the colors, place in front of a white paper  or white wall. Check the resulting a cor and its respective pH:


Color ..... ..... ..... ..... ..... ...pH
Red: ..... ..... ..... ..... 2
Violet Red: ..... .. 4
Violet: ..... ..... ..... ..... .... 6
Violet Blue: ..... ..... ..... 7
Blue: ..... ..... ..... ..... ........ 7.5
Greenish Blue: ..... .... . 9
Bluish Green: ..... ..... ... 10
Green: ..... ..... ..... ..... ...... 12.



Building a peagameter



- 2 9 volt batteries

- 2 pole 9 volt batteries

- BNC connector

- BNC panel



How to do it? 


  1. Connect each 9 volt battery to its own pole.

  2. Connect the negative pole wire of the first battery to pin 4 of the TL082 integrated circuit chip and solder the connection.

  3. Connect the positive pole wire of the first battery and the negative pole wire of the second battery with the BNC ground lock and solder the triple connection.

  4. Connect the wire from the positive pole of the second battery to pin 8 of the TL082 integrated circuit chip and use the soldering iron to solder the connection.

  5. Connect the BNC connector to the BNC panel. Attach the pH probe to the non-inverting BNC connector output by screwing it in.

  6. Connect the integrated circuit chip to the BNC board and solder the connection behind the BNC connector.

  7. Connect pins 6 and 7 to the TL082 integrated circuit chip by soldering the two pins together.

  8. Connect the positive lead from the voltmeter to the solder connection on pins 6 and 7 on the chip and use solder to secure the connection.

  9. Solder the negative lead from the voltmeter to the BNC ground lock.

  10. Calibrate the pH meter by testing pH levels in different solutions. The pH probe will output approximately 59 millivolts per pH unit. Neutral pH (pH 7) will produce 0 volts. Negative voltages will be produced by an acidic pH while a basic pH will produce positive voltages.



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