I CANT GET THIS TO WORK ANY ONE HAVE ANY HELP
NOTES OR POINTERS ASK ME WHAT YOU NEED TO KNOW
IT IS ALL ON A PROTO BREAD BORD I CHECK ALL THE PARTS ARE RIGHT ASK ME WHAT YOU NEED TO SHOW WERE I FAILED I MADE TWO COILS THE SAME TO TEST IT BUT NO CHEEPING IT WILL MAKE NOIES WHEN I PULG IN THE COILS BUT THEN STOPS
I am sorry, but there is not much that I can say about that circuit which will be very encouraging to you.
The correct operation requires two oscillators to be running at (nearly) the same frequency.
There are no adjustments built in to the design to allow this to happen.
The frequency of the oscillators will depend very much on the actual values of the components, and the normal tolerance of the components will be about 5 to 10 percent, enough to set the oscillators so far apart in frequency that you will not hear them beating together.
The audio stages which feed the loudspeaker are a very good example of how NOT to design audio amplifiers.
The results you get will be very dependant on the exact characteristics of the transistors and the ambient temperature.
I visited the website which you give the link for, and saw how he was slagging off others for copying his design.
If I had designed this circuit, I would keep very quiet about it. Really!
I agree that if I designed that....I would rather not talk about it...I learned stuff there though about how not to build a Metal Detector.
I have always wanted to build one though....a proper one...since I was a kid. I have had this thing in my head for years now when taking a walk along the beach with the dogs leashed to one hand and the light, sensitive MD in the other hand....
The MD starts screaming.....I stop. Show the dogs where to start digging....they dig and expose a Treasure Chest. Just a little dream, but a good one.
If you cannot dream if you have nothing to live for
I am going to build a proper Metal Detector at last. Based on a solid published design....if I can find it on the Web. I know Elektor from way back had some nice designs....years ago though.
I visited the website which you give the link for, and saw how he was slagging off others for copying his design.
If I had designed this circuit, I would keep very quiet about it. Really!
But you can TUNE the Frequency by Starting with Two Round Coils.
Than FLATTEN One or the Other Coil as needed. (NOT BOTH.)
Flattening a Round Coil to an OVAL SHAPE will change its Inductance and Frequency of Oscillation.
You are clued up on these matters. Care to give me pointers where I can find diagrams/built units that are up to the precision standards that are at the cutting edge today?
Like smart stuff that is worth building/buying? Not a learning tool. Proper up to date stuff
You are clued up on these matters. Care to give me pointers where I can find diagrams/built units that are up to the precision standards that are at the cutting edge today?
Like smart stuff that is worth building/buying? Not a learning tool. Proper up to date stuff
I CANT GET THIS TO WORK ANY ONE HAVE ANY HELP
NOTES OR POINTERS ASK ME WHAT YOU NEED TO KNOW
IT IS ALL ON A PROTO BREAD BORD I CHECK ALL THE PARTS ARE RIGHT ASK ME WHAT YOU NEED TO SHOW WERE I FAILED I MADE TWO COILS THE SAME TO TEST IT BUT NO CHEEPING IT WILL MAKE NOIES WHEN I PULG IN THE COILS BUT THEN STOPS
When a common-emitter transistor (like the two transistors with the coils) has its base DC shorted to its collector (by the coil) then the transistor does almost nothing.
When a common-emitter transistor (like the two transistors with the coils) has its base DC shorted to its collector (by the coil) then the transistor does almost nothing.
When a common-emitter transistor (like the two transistors with the coils) has its base DC shorted to its collector (by the coil) then the transistor does almost nothing.