Look at this schematic - Need help please

[eightwgt]

led works......

Im not usin a bread board - sodered it up on a little board from Radio shack...

 

[Nostrafus]

okay, well then I guess my first Idea wouldn't matter... hooking up a component on a breadboard horizontally is a no-no, it'd be like making a PCB with wiring like this ---0----0--- and we all know that doesn't work

anyway, just keep messing with it, and 1K is Brown/Black/Red fourth stripe is the tolerance if yours has one, if not, doesn't matter.

 

[eightwgt]

Looking at the transistor from the TOP-its shaped like a D right... So, you hold it looking at the top so the arc is too the right or as the letter D is written, the Emmiter wire would be thetop wire correct ?? The Middle is the base obviously, and the collector would be the bottom wire...... Im just makin sure I didnt hook up the transistor backwards... if I did would it have blown the transistor ?? I am using a 9 volt battery by the way -

 

[Nostrafus]

No, it wouldn't have blown the transistor, but it wouldn't work right, the emmiter should be going toward negative, so try reversing the transistor.

 

[Mosfet]

-

 

[eightwgt]

Mofset.... whats a common mistake I may be making ??

 

[Sebi]

If You make a shortcut between electrodes it work?

 

[eightwgt]

GOT IT !!!!!!!!

i got it working..... works perfect for what I need.... now i have to put it on my caliper configuration.....
THANKS GUYS !!!!!!!!

I appreciate the help

 

[Nostrafus]

okay, what was wrong ?

 

[eightwgt]

as far as i can figure, i must have had the trasistior wrong

 

[Mosfet]

Congratulations! You didn't give up. Feels pretty good, huh?

 

[eightwgt]

Mofset......

Feels great ! I am a happy camper. I was not about to give up ! The application I am using it for works very well and the circuit is perfect although the only problem is the tip of the conductor probe is getting eaten away a little at a time so that makes for constant adjusting.... If I lowered the voltage requirement can I still make it as sensitive ? Now the Darlington would be a good canidate right ? Doesnt it help increase the voltage so I could drop the voltage going into the probe...... I wonder if it would still get eaten up as bad ? I started turning it off as soon as it contacted the water and I got a reading.... that helps.
As far as the water level I made... Its a little crude but accurate over a 10' distance to about .002"-.003". I took multiple readings and averaged out the differance measuring with calipers, and it could be improved to a consistant .002" if I tighten everything up so measuring can be more consistant....

Anyway - Thanks again ! I appreciate it a lot.

 

[Phasor]

the only problem is the tip of the conductor probe is getting eaten away a little at a time

Try using a silver or gold plated probe. It won't oxidise as easily.

 

[kinjalgp]

Use stainless steel probes. They won't have any problem of rusting or other reactions. I have used in my water level controller and its still working since past 6 years.

 

[Nostrafus]

Or you could use aluminum, it's already got an oxidized coating and water doesn't damage it, that's why it works so well with soda, I mean hell, soda is basically a weak acid and it doesn't even scratch aluminum, and even if it does get a scratch in the aluminum past the oxide coating, exposing it to air for roughly 30 seconds will put a new one over the scratch.

 

[eightwgt]

HEY GUYS

BEEN A LONG TIME........ but here is what I used that little gadget to build....... (well help build )

https://www.inshorepowerboats.com/cnc stuff/CNCROUTER.htm


Thanks again

Tom

PS anyone know any ideas on a DC motor control ??? :shock:

 

[Crofty]

Mofset

Thanks again.....

i just got an assortment of resistors... trying to figure out which is the 470 !!

Thanks

Yellow, Violet, Brown (then gold/silver for tolerance)

Steve