ETI 566 Project _ Tx Coil 4 Pins Connections

[ZuMi77]

Dear Carl-NC,

This is regarding ETI 566 project. I need to make sure the transmitter coil L1 four pins connections are correct. On the transmitter pcb overlay I have marked the L1 4 Pins as 1, 2, 3, 4. On an earlier version of the article I have marked the Tx L1 4 Pins as A, B, C, D. In the article I've found on geotech1 the arrangement is:

Pin A ..... Pin 1 .... Q1 collector

Pin B .... Pin 2 .... Ve-

Pin C .... Pin 3 .... RV1, C2

Pin D .... Pin 4 .... C4, CV1

Is there something wrong? Don't we have to swap Pin C & Pin D connections?

[Carl-NC]

Both of your labeling schemes are wrong. From the pics you posted, they should be

Pin D ..... Pin 1 .... Q1 collector

Pin C .... Pin 2 .... Ve-

Pin B .... Pin 4 .... RV1, C2

Pin A .... Pin 3 .... C4, CV1

Unless I have the whole coil upside-down.

[ZuMi77]

Thanks Carl for taking time to respond. So the configuration in the image at the bottom right (in the pdf) is incorrect.
One more question if you don't mind, is there something wrong with R1 27 KΩ & R2 180 KΩ? Should their position or their labels be swapped?

[Carl-NC]

Sorry, I had it upside-down. The bottom-right labeling is correct, so is the bottom-left.
No idea on the resistor values. They look suspicious, but maybe they're right. I've never built this circuit and know nothing about it.

[ZuMi77]

On the pcb layout this is what we can see:

1 ..... Q1 collector

2 ..... Ve-

3 ..... C4, CV1

4 ..... RV1, C2

On the bottom right image:

1 ..... Q1 collector

2 ..... Ve-

3 ..... RV1, C2

4 ..... C4, CV1

We have:

the order in the image at the bottom right.

the order in the pcb layout.

3 & 4 are swapped.

In an older version of the article it is stated that the "4 pins connections can be taken from the pcb layout" which is included here in the pdf. If I want to follow the order in the pcb layout, then I have:

1 .... Q1 collector

2 .... Ve-

3 ..... C4, CV1

4 ..... RV1, C2

That means, C4, CV1 & RV1, C2 in the bottom right image should be swapped. Am I correct?

[Carl-NC]

Do it this way: