>Band L
>
>80 13.6
>40 6.5
>20 1.75
>15 1.0
>10 0.8
>
>Now I have just created a spreadsheet for Pi-networks where I can vary
>the tube impedance and the Q of the Pi-net. I can't find a combination
>where the L needed in the circuit matches what B&W provides. It is
>certainly screwed up for my 4-1000A impedance of around 5000 Ohms.
Ok, I did some more figuring. I decided that no law says that the value
of Q has to stay fixed from band to band. So, I did some playing in the
spreadsheet and found the following given the values of L above:
Frequency Q C1 C2 L
-------------------------------------------------------------
3.75 MHz 18 141.4 pF 1135 pF 13.7 nH
7.15 MHz 20 82 pF 691 pF 6.52 nH
14.2 MHz 38 78 pF 747 pF 1.776 nH
21.2 MHz 45 61.5 pF 597 pF 1.0 nH
28.3 MHz 42 43 pF 416 pF 0.8 nH
So, I guess it is possible to use real world value components in this
example, but the Qs get awfully high.
I guess I am asking for some help here because it seems like the Q values
get a bit high. Is this a good matching circuit design or not?
73,
Jon
KE9NA
-------------------------------------
Jon Ogden
KE9NA
http://www.qsl.net/ke9na <--- CHECK IT OUT! It's been updated!!!!!
"A life lived in fear is a life half lived."
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