berger.h
Member level 5
I have before me the device containing
LC Impedance matching network transforming Zi 6Ohm to 50Ohm , passes through it sin 10MHz, 35V 100W. See picture.
If I calculate this network have
L=259nH, C=862pF
I device is used 7 pcs 1210 SMD silver mica capacitor and as inductor toroids T130-6 iron powder with 3 turn.
My question.
Why is used 7 pcs capacitor? Silver Mica is expensive and 862pF can be folded with 3pcs.
Is it a good idea replace silver mica with ceramic NPO ?
Silver mica have TC +-25ppm/C, NPO +-30ppm/C
Quality Q silver Mica 150pF is about 1500, where can I find Q NPO 150pF?
Inductor , if I use this tools must this core for 259nH 5 turn but my toroid have only 3 mayby 3.75 turn. Why?
LC Impedance matching network transforming Zi 6Ohm to 50Ohm , passes through it sin 10MHz, 35V 100W. See picture.
If I calculate this network have
L=259nH, C=862pF
I device is used 7 pcs 1210 SMD silver mica capacitor and as inductor toroids T130-6 iron powder with 3 turn.
My question.
Why is used 7 pcs capacitor? Silver Mica is expensive and 862pF can be folded with 3pcs.
Is it a good idea replace silver mica with ceramic NPO ?
Silver mica have TC +-25ppm/C, NPO +-30ppm/C
Quality Q silver Mica 150pF is about 1500, where can I find Q NPO 150pF?
Inductor , if I use this tools must this core for 259nH 5 turn but my toroid have only 3 mayby 3.75 turn. Why?