Step 7 question

[homefire]

There's not current without the coil in place. What is the Resistance and Inductance of the coil ?

[omr255]

There's not current without the coil in place. What is the Resistance and Inductance of the coil ?

http://imgur.com/a/AVthN

[omr255]

C7, C10, C11, C12, C13, C14 and C21 are all the wrong values in your photo.
None of these are polarity sensitive.

Update: OK - I see that you've now changed those in your latest photo.
There must be something else wrong that's not obvious by looking at it. I can assure you that this design works exactly as described, so you must an error somewhere. It's very difficult to debug remotely and without a scope.

I cannot see anything out of place bu looking at the pictures.
Could it be one of the ic chips, fets or voltage regulators that are malfunctioning?

[omr255]

Now for some unknown reason the lf412 seems to have shorted as it nolonger give a 5v, -5v or even pin 1 voltage.

[chevesne]

http://imgur.com/a/AVthN
Inner radius is half the diameter.

[Qiaozhi]

http://imgur.com/a/AVthN

As chevesne has pointed out, it appears from the Coil Calculator that your coil diameter is 520mm.

Did you not read the instructions where it says: "One common mistake is to enter the diameter of the coil, instead of the radius, into the first field of the dialog box."?

I know some people believe that they've failed if they have to read the instructions, but so far you're managing to disprove that theory.

[omr255]

As chevesne has pointed out, it appears from the Coil Calculator that your coil diameter is 520mm.

Did you not read the instructions where it says: "One common mistake is to enter the diameter of the coil, instead of the radius, into the first field of the dialog box."?

I know some people believe that they've failed if they have to read the instructions, but so far you're managing to disprove that theory.

My mistake.
The lf412 seems to be working again.
I have made a 24 turn 13cm radius coil from .5 mm wire and now the mosfet gets a tiny bit warm to the touch.
But I still can not get the voltage on u7 pin 1 to change by turning r14.

[omr255]

Anything which could be causing r14 to not adjust voltage on u7 pin 1?

[omr255]

I have replaced r14 and now when pl2 pins 1 and 2 are shorted, the voltage changes between 0 to +3 volts. There is no negative voltage. When pl2 2 and 3 are shorted, the voltage remains -2.45v no change when pot turned.