To: <amps@contesting.com>
>Date: Wed, 13 Nov 2002 09:26:46 -0500
>To: "mark" <mark@sandlabs.com>
>From: wl fuqua <wlfuqu00@uky.edu>
>Subject: Re: [Amps] EIMAC Confusion
>
>ALEX,
> DCVxDCI is the total power supplied to the amplifier or total power
> consumed not the total device dissipation.
>
>Plate dissipation is the power dissipated on to the plate by the kinetic
>energy of the electrons when they strike it.
>
>Filament and grid dissipation are not properly called parasitic due to the
>fact that the power that they dissipate is
>fed directly to them. Parasitic means that they get power from other
>elements. Such as in a yagi antenna with parasitic
>elements. Those elements get energy from the driven element and are not
>fed them selves as in a phased array or
>log periodic antenna.
>
>
>At 07:44 AM 11/13/02 -0500, you wrote:
>>Thank you all for the replies :)
>>I am a Solid State kind'a guy. There, things are relatively simple. TOTAL
>>DEVICE DISSIPATION (TDD) is DCV times DCI`. The ratio between TDD and OUTPUT
>>POWER (OP) defines the
>>efficency of the device. For example a 100W TDD transistor delivering 50W OP
>>is sayd to have
>>a 0.5 (or 50%) efficency.
>>Here, in the Tube world it gets a bit more complicated as I have to contend
>>with "parasitic" sources (like the filament and eventual grid source(s) )
>>and there is no explicit text that I found yet that will explain it's
>>(their) contribution to the TDD parameter.
>>
>>
>>
>>Mark
>>
>>
>>
>>
>>
>>
>>----- Original Message -----
>>From: <i4jmy@iol.it>
>>To: "mark" <mark@sandlabs.com>
>>Cc: "amps" <amps@contesting.com>
>>Sent: Wednesday, November 13, 2002 4:52 AM
>>Subject: [Amps] Re: [Amps] EIMAC Confusion
>>
>>
>> > Mark,
>> >
>> > I think you did not understand how does it work.
>> > As the word says, the plate dissipation is the energy dissipated, not
>> > the total power involved.
>> > If a tube FM amplifier (typically a class b) has roughly 70% plate
>> > efficiency, @ 2600W out the plate dissipation is 1114W.
>> >
>> > 73,
>> > Mauri I4JMY
>> >
>> >
>> >
>> > ---------- Initial Header -----------
>> >
>> > >From : amps-admin@contesting.com
>> > To : <amps@contesting.com>
>> > Cc :
>> > Date : Tue, 12 Nov 2002 22:18:48 -0500
>> > Subject : [Amps] EIMAC Confusion
>> >
>> > > In the EIMAC Technical Data for the 8877/3cx1500A7
>> > > is is stated in the ABSOLUTE Ratings the Plate Dissipation
>> > > is 1500W. I take this as an ABSOLUTE MAX.
>> > >
>> > > However in the TYPICAL Operation at 88-108MHz USEFUL POWER OUTPUT
>> > > is rated at 2600W.
>> > >
>> > > Is this meaning that the tube is providing 2600W to the load while pla
>> > te
>> > > dissipation
>> > > is only 1500W? Is this possible ? If so What is then the TOTAL TUBE
>> > > DISSIPATION
>> > > and how is the filament power related to it ?
>> > >
>> > > Mark
>> > >
>> > > _______________________________________________
>> > > Amps mailing list
>> > > Amps@contesting.com
>> > > http://lists.contesting.com/mailman/listinfo/amps
>> > >
>> >
>> > _______________________________________________
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>>
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