Home > Electronics > Stupid #@%#$^# hydroponics automation project

Stupid #@%#$^# hydroponics automation project

March 30th, 2008

In an attempt to clean up my laundry room, I decided to put a bit more time into my hydroponics automation project (parts of which were scattered all over).  Talk about problem after problem.  First off, I forgot to put a reverse biased diode across a relay and blew my power supply (it always blows fuses, tired of fixing..).  Then one of the optoisolator darlingtons  (from sparkfun) didn’t work, so I had to swap in a non-darlington optoisolator I had and lower the value of the current limiting resistor to get it to work.   I put all this inside the bottom of the blue box, went to wire it to the 3-prong power socket, but not only ripped the solder pad off from where the wire attached to the board, but I also ripped off the relay pin.  So I swapped out that relay with a spare I had, put it all togehter, but it didn’t work.  Seemed there was a bad solder joint in there so I took it all apart, fixed, and put it back together.  What took about 6 hours should have been at most an hour… I need to get my mill operational so I can fab my own PCBs rather than messing with the project boards of crap from Radio Shack.


Anyhow, I feel like I’m past that hurdle, spend some more time with wiring and stuff, tweaked the firmware to add some functionality, and went to program it — but vista complained about the hub not having enough power or something.. So I got up to unplug the AVR Dragon, dripped over the USB cabe to my PCB which was attached via an SMD USB-A connector.  Rather than coming it of the plug, it ripped off all the pads… Here’s a photo of it…Notice the USB connector on the DB-25, and the ripped pads in the bottom center of the PCB..


  1. | #1

    Fixed it with some fine soldering and epoxy; now the FETs are doing strange things.. *sigh* Time to put this project back on the shelf for a bit longer..

  2. octotats
    | #2

    have you got a working auto doser setup yet? I am interested in what you used for dosers and how you integrated them with your usb ph meter. I am attempting to create the same using Allen Bradley PLC and hanna continuous ph meter. What are you using as a doser and is it accurate?

  1. No trackbacks yet.