Recent content by Dan90

I'll add one of the 3.3k Ohm resistors in series with the meter like you suggested earlier. By destroying the meter do you mean bending the needle by passing to much current in either direction through making the needle hit the wall? Or damaging more then just the needle?

Been a while since I've looked at it. I did manage to create probes out of two old push bike wheel spokes. It works properly now. I've been using sand to play around with it, a fair bit cleaner than soil. Anyway, I was just playing with it and I noticed that if the capacitor is removed, there...

I'll try making the circuit work without the transistor first. I don't fully understand where the probes would go if you removed the transistor. I'll post the placements of what I currently have and what I think I should do: Currently working places with the pot in place of the two 3.3k ohm...

Sorry for the slow reply, went on a brief holiday. Anyways, I tried the soil moisture monitoring this arvo and it seems more responsive to play with. I tried it at first with the original setup of the circuit. So far I've only dumped a handful of dirt from the garden in an ice-cream container...

I did try replacing the 2 3kohm resistors with the pot then moving one of the resistors to where the pot was. I didn't appear to have anything happen with adjusting the pot, so I changed it back because I had someone helping me to try to test skin resistance. Some meter movement is a bit better...

Will head down to jaycar tomorrow and see if I can pick one up. It should be the same, if not similar to the pot I already have. The meter I am using did come from jaycar. I would imagine someone would have the center-zero meters, which would be much more handy in providing detail, but as...

Yes, I'm an Aussie. I live about 40 minutes from Brisbane. I'll take a look for a center-zero meter, It would be helpful, but I should be able to make do with my existing one. If the current goes below zero it does drop down so you 'can' see the change in amperes, but you don't get an actual...

I'm not too sure if the meter goes through zero, I haven't had a chance to play with it since Monday night, will get a chance this arvo. I do know that I can touch the wires together making the meter reach zero then scale the pot so the meter will go up positive away from zero. The pot...

You are right, when the "electrode" wires are connected together the meter does reach zero. What I wanted to try was to connect another pot where the electrodes were to see if I could balance it that way, just didn't have one because I wasn't at my house when I got it working. The spoons are...

Thanks for picking up on those errors. I made the changes and added in the extra jumper wire. I connected the multimeter instead of the analogue meter and actually obtained a ampere reading. I took the multimeter off and reconnected the analogue meter and I have a reading. All I need to do...

Cheers, i'll check that tomorrow morning. I guess I picked a somewhat difficult circuit for a first project. This will feel like the greatest achievement for me to date if I can get it working. Will post results tomorrow morning.

Gave the circuit another test using your diagram, but unfortunately I didn't get any results. I would think that I still have something connected up wrong so far. Instead of the analogue ammeter I just set my multimeter to amps mode and used it in place. This is another list of the places...

I can follow the majority of the diagram. The only thing that has me confused is the placement of the pot on your diagram. Are all three wires of the pot connected right where the dark black squares are? I'm not sure what the arrows down from there mean, is it something similar like the...

Thank you for the help guys. I will have to try your suggestions after I finish work this afternoon. With the breadboard, I tried to connect through the columns rather than rows, I'm not sure if they can work this way tho. I will try to connect them similar to the diagram that vk6kro has...

Sorry if I post this in the wrong section. I am attempting to build a "simple lie detector" circuit which is floating around on the internet with a simple google search, but I am having trouble physically building the circuit and obtaining results. I've drawn the circuit in a simulation...