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Impedance output match network -compoment choice?

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berger.h

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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?


Output matchj.png
 

Is it a good idea replace silver mica with ceramic NPO ?
Click to expand...
Possible if you use power RF capacitors, e.g. from Johanson Technology. Expect a rated DC voltage of >=500V for 100W.

but my toroid have only 3 mayby 3.75 turn. Why?
Click to expand...
No idea how you see 3.75 turns. Really no chance to implement fractional turns on a toroid core.
- core is not 130-6
- circuit has additional wiring inductance
- source impedance is not 6 ohm with zero reactance
 

Thank you for your response.
1.
>Rated DC voltage of >=500V for 100W.
Why 500V? PA is amplified with 35V even if 50V with big reserve.
Although I counted 4 times higher voltage should be enough 200V?

2. >core is not 130-6
I measured dimension corresponds to the size T130 and core is painted yellow with one side clear yellow/clear is color code pro material number 6
>source impedance is not 6 ohm with zero reactance may be,
6 Ohm I calculated form capacitor size (is market on capacitor) and know impedance size on second side is 50 Ohm
But this is not the key question, key are capacitors and the number of capacitors.
 

Code: 
Possible if you use power RF capacitors, e.g. from Johanson Technology. Expect a rated DC voltage of >=500V for 100W.
Why 500V if DC supply voltage is 35V , I thing 200V is sufficient or not?
Johanson Technology is goog choice, but for high frequency 100MHz and more. On 10MHz is questionable use ordinary capacitors, and ceramic capacitors from Samsung have on 10MHz similar Q as Johanson Technology RF capacitor.
 

Thank you for the information.
I loot **broken link removed**
and on 15MHz have ESR=12 mOhm, Ls=190 pH, Q=6023
this is full comparable with Silver Mica , question is RMS current and High RF current
silver mica have High RF current dV/dt 20,000 V/μs and Maximum RMS Current 150pF 2A
 

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