Amps
[Top] [All Lists]

Re: [Amps] again

To: "Roy Koeppe" <royanjoy@ncn.net>,"Amps Reflector" <amps@contesting.com>
Subject: Re: [Amps] again
From: "Mike(W5UC) & Kathy(K5MWH)" <w5uc@cox.net>
Date: Sun, 2 Jul 2006 10:22:29 -0500
List-post: <mailto:amps@contesting.com>
Roy, I agree.  This came up because I found a schematic for a pair of 
Gi-7b's and was kinda using it as a guide. Meanwhile back at the ranch, I 
looked up the formulas for calculating the values in a pi-network in the 
ARRL Handbook, and put them into a Microsoft Excel spreadsheet. 
Interestingly, when I did the calculations for my operating conditions, and 
those in the schematic, they were far apart as far as values are concerned; 
thus the reason for the inquiry here on the reflector. I will probably go 
with the values that provide the correct match for the operating conditions 
in my amp.  Thanks for the response.

73,
Mike, W5UC
http://members.cox.net/w5uc


----- Original Message ----- 
From: "Roy Koeppe" <royanjoy@ncn.net>
To: "Amps Reflector" <amps@contesting.com>
Sent: Sunday, July 02, 2006 9:32 AM
Subject: Re: [Amps] again


> This question,
>
> "There clearly are individuals on this reflector who are more
> knowledgeable than me, so I will ask this question again, but in a
> differently worded form.  How does the impedance of the PA tank affect
> the over-all efficiency of the amplifier? W8JI said yesterday that a
> tank whose impedance is, say 2100 ohms, and connected to a Pa with a
> calculated load impedance of 1333 ohms would produce a very efficient PA
> but it would have poor linearity.  BUT, what happens to efficiency if
> the tank impedance matches the load impedance?   Again, how does the
> impedance of the PA tank affect the over-all efficiency of the
> amplifier?  Inquiring minds want to know."
>
> Hi,
>
> I think your question is of a much more elementary nature than others
> have assumed it to be. In the case of a  typical tank circuit having
> typical operating Q of say 12, when you adjust C1 and C2 for maximum
> output, you are indeed adjusting for an impedance match of the tube and
> the load and for maximum efficiency all at the same time without
> consciously or deliberately thinking about it.
>
> 73,   Roy    K6XK
>
> _______________________________________________
> Amps mailing list
> Amps@contesting.com
> http://lists.contesting.com/mailman/listinfo/amps 

_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps

<Prev in Thread] Current Thread [Next in Thread>