>Both - but what's the difference? An amplifier set up to give 100W using a
>2000V supply or a 1kW amp using the same ht have the same requirement.
? The requirement is seemingly set by the conditions under which the
amplifier is tuned up. Assuming 60% effiency, if a 1666w input, w. 2000v
anode supply, 1000w-out amplifier is, , tuned up at 1666w input, approx
0.833a of anode current is required. Therefore RL is roughly. 2000v/(2 x
0.833a) = 1200 ohms and the Pi-network tank circuit must be tuned to
match 50 ohms to 1200 ohms. Assuming that the drive level is susequently
reduced until the output is 100w, the anode-V swing is reduced and the
anode-I swing is also reduced. In my opinion, when the output of this
amplifier is 100w, RL does not become 22k-ohms. . However, if it were
decided to tune up the amplifier for operation at 100w out, RL would
increase to roughly 22k-ohms.
>The point I was trying to make, and which you are conveniently ignoring, is
>that the RL in either case is radically different if you use the formula I
>posted previously.
>
Semi-agreed. . However, the RL formula is an approximation that applies
for the power level at which an amplifier is tuned. When drive is
reduced to a tenth, RL does not increase ten-fold. .
- later, John
....................................................................
>> From: Rich Measures <measures@vc.net>
>> To: John Fielding <johnf@futurenet.co.za>; Amps Contesting
><amps@contesting.com>
>> Subject: Re: Fw: [AMPS] Anode load line calculations.
To: <amps@contesting.com>
>> Date: 21 December 1998 03:39
>>
>>
>> >
>> >But Rich you misunderstand what I am trying to tell you and the
>others!!!!
>> >
>> >The anode voltage swing WILL be the 80% or so of the dc supply voltage -
>> >but it is now developed across a much higher impedance of 22800 ohms.
>>
>> ? John: Are we talking about a 100w amplifier using a 2000v anode
>> supply, delivering 100w - - or are we talking about a 1000w amplifier
>> using a 2000v anode supply, delivering 100w because of reduced drive?
>> - thanks
>> >.......
>>
>>
>> Rich...
>>
>> R. L. Measures, 805-386-3734, AG6K, www.vcnet.com/measures
>>
>>
>> --
>> FAQ on WWW: http://www.contesting.com/ampfaq.html
>> Submissions: amps@contesting.com
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Rich...
R. L. Measures, 805-386-3734, AG6K, www.vcnet.com/measures
--
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