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Codyhtml's Achievements


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  1. I'll Double check the voltages and fix the LEDS and see what happens Thanks for all your help I have 4 AA Ni-cad batterys that should be able to give the current and voltage plus in the day time i have the solar panels it could draw on
  2. ok pins 1-9 of the 3915 1| 3.8 2|.4MV(basically zero) 3|5.44 4|.4MV (same as 2) 5|.64 V 6|1.5 7|3 8|3 9|5.4 The Led's will light when not connected the the circuit i saw that i had connected the pot wrong i corrected that and the leds would light but my leds are just misc. ones from my drawer and one of my red leds meaning dry is on always i don't know if it is the leds or the circuit because the other leds just dim when i adjust the pot until they are barely visable i put in a switch to change between dot and bar and when it is in dot i don't see anything please help EDIT: when in dot i do see one green led (second from first meaning wet) when the probes are dry does the 3915 work high number down? whoops i realy messed this project up :( i connected pin 1 of the 3915 in the wrong spot i connected it next to the led for pin 10 on accident so that probably explanes some of the wierd things
  3. I didn't have a 2.5k trimpot so you said to use a 2k and a 510 ohm resistor I wasent guessing i must have been distracted or tired or something and i was thinking that the long wire was the cathode but i wasent thinking right at the moment
  4. I don't think so except i didn't have a 510 ohm resistor and i made like a 500ohm or something so it should be fine and i think one other resistor i had to make my own but i came pretty close (by make my own i mean put two resistors in series) i found two mistakes that i thought i made and fixed them i thought i hooked up the leds backward but when i switched them it didn't fix anything (oopa i'm dumb i had forgot to connect one on the ics to ground so i did that and switched the leds but i realy had the leds on right ::) in the first place looks like its time two switch them again :( lol
  5. Ok Hi i guess you forgot that you helped me modify this and i don't have a led i have a led bargraph display lol my batterys are meashring a little over 5v on pin 6 i get1.3V on pin 3 i get1.6V on pin 8 i get .64 V on pin 11 i get 2.3V My ics are i'm guessing you want all of it so here it is poo52AD MM774HC132N MM774HC132N THAT IS EXACTLY HOW IT IS ON MY FIRST ic (YES I KNOW THERE IS A REPEAT ITS THERE TOO OOPS HAD CAPS LOCK ON LOL) NEXT JB536RA LM3915-1 That is how my other ic looks exactly (except for a little logo i can't type ps i don't feel any wormth on the ics if that helps
  6. I do have to agree but for this year i'll make a second smaller compost pile and see if i can see a difference in them
  7. I got an idea what if I took a PVC pipe and put it in the corner of the compost pile and filled it with the same material as the other compost and put the probes into that. PVC is a great insulator and that might even help if any current went out of the bottom of the pipe and into the normal soil mabe it would make the worms want to go into the compost and stay there. I don't Know but what do you think about that idea. The pipe should dry out at about the same rate as the rest of the pile woulden't you think?
  8. so i need to find out wil it ruin my compost pile and is there any way to keep it from ruining my compost pile (putting it in the corner something?)
  9. that should be fine the main purpose of the solar cells is/was to extend the battery life. I can charge the ni-cads in a charger and the solar panels should keep them topped off for a while. Essentially making up for the extra draw of the bargraph/moving dot display. I guess i can experiment with the probes i don't see what would be a problem though For the charger just any general purpose diode right Thanks once again for your help if i get it all worked out mabe this could be another project since this is a fairly large mod :D EDIT: one more question the 2.5k resistor that I see in the circuit (on the LM3915) is that a POT if it is what kind linear, Logarithmic and what pot from here http://www.futurlec.com/Potentiometers.shtml would be the best to use?
  10. Ok i'm not sure if i know how to build a simple ni-cad charger from my solar panel can you help me with that? How do i make several sets of probes do i need to do anything special?
  11. Ok thatks that is awsome thats the basics of what i need now how can i use two solar panels to charge 4 ni-cads such as what the solar yard lights do and can i have two or even three sets of probes to get a more acurate reading from the whole compost pile not just one spot? thatks for your help so far oh and in my schematic i left it a moving dot displayon purpose i decided that is all i need that way i save battery life and reduce power consumption
  12. ok well I did my home work and this is what I got the ares in red I wanted to bring attention to because i figured i might have made a mistake there EDIT: I got thinking do i need to calibrate this and if i do how?
  13. ok great my solar panel gives about 4v in bright sun could I modify the the charging circuit (witch i might have to to disable the off at day and the on at night anyway) to use 3 double a cells or if I need to I could probably use two lights so I have 2 panels and 4 batteries what would be the easyest and best? and what about two sets of probes how easy/hard would that be? I just got another thought what if i ran the bargraph display off the solar panel that would give it 3.5-4V and it would not be on at night which is not needed
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