Comparative measurement between 67 and 73 material.

I made a 1:1 transformer with 

3 turns primary and 

3 turns secondary.

The coil value of 3 windings of the 67 material is 4.7 μH @ 1 MHz.

The coil value of 3 windings of the 73 material is 300 μH @ 1 MHz.

The impedance of the coil with 67 material @ 1.8 MHz = 53 Ohms.

The impedance of the coil with 73 material @ 1.8 MHz = 3400 Ohms.

The results:

67 materiaal due to the low impedance we have a bad SWR @1.8 MHz:

73 materiaal:

IL 67 material:

IL 73 material:

Compensation for 14 MHz

I did a new measurement to be able to compare before and after compensation.

Before:

Impedance @ 14.1 MHz = 53 = J30 Ohms.

Calculation of the compensation with the use of a smith diagram:

I have placed an SMD capacitor of 91 pF at the input.

In detail:

After:

Due to the high inductive behavior, I reduced the number of windings to 2 and then to 1 respectively.

Two turns P and S:

One turn P and S: