Experiments with LC circuits    part 2

The tuner capacitor is C1b.

 Coil L6. This coil has no coilformer. The wirelength on the coil is 12.5 meter, and two leads of 0.25m. So, the total wirelength is 13.0 m. The inside diameter is about 11 cm. Number of turns: 32. Wire: litz 40x0.07mm The intersections of the wires are glued together
 Measurement  number LC combination F min  kHz F max  kHz Q 600 kHz Q 900 kHz Q 1200 kHz Q 1500 kHz 12 L6 C1b 512 2075 317 340 279 243

In the next experiment the coil is divided over two coilformers.
The outside diameter of the coil is now reduced, and the receiver can be build more compact.
The distance between the coilformers is adjustable, I made measurements with distances of 10, 20 and 40 mm.

 Coil L7 This coil has two coilformers of foam PVC. Each former is wound with 6.25 meter wire, and there are two leads of 0.25 m. Total wirelenght is 13.0 meter. Wire: litz 40x0.07 mm. Number of turns: 29 per former, so total of 58. Inside diameter of the coil: 50 mm. The coil must be wound on both formers in the same direction.
 Measurement  number LC combination F min  kHz F max  kHz Q 600 khz Q 900 kHz Q 1200 kHz Q 1500 kHz 13 L7 C1b 10mm distance 460 1926 332 324 265 220 14 L7 C1b 20 mm distance 511 2190 287 334 255 224 15 L7 C1b 40mm distance 550 2370 283 301 255 216

The next coil has less wire then the coils before.

 Coil L8 The wirelenght on the former is 6.5 meter, and the two leads are 0.25 meter. Total wirelenght is 7 meter. Wire: litz 40x0.07 mm. Coilformer material: foam PVC. Coil inside diameter: 50mm. Number of turns: 30.
 Measurement  number LC combination F min  kHz F max  kHz Q 600 kHz Q 900 kHz Q 1200 kHz Q 1500 kHz 16 L8 C1b 816 3490 * 303 287 269

Because of the shorter wirelenght, the minimum frequency is not very low, but the Q at 1200 and 1500 kHz is higher then all coils before.