There is still something left out of all this.
If referencing an AL80 amplifier; it is only an amplifier not a plate modulated stage.
In cathode drive, the driving power minus losses is passes on through and adds to the 'amplified signal' developed from grid modulating current flow from the DC power supplied to the tube.
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For AM use with this amplifier, you can only run this amplifier to about 150 watts of carrier and talk for short periods of time without overdissapating the tube's plate.
Why: 3000 volts times .150 amp = 450 watts DC 'carrier' power. The tube's plate dissapation is not rated for much more than this.
When the modulated drive signal increases with speech, the average tube dissapation goes up greatly and begins to 'average shift' to higher plate temperatures as seen by the plate continuing to get brighter and brighter with key down time and no chance to cool.
This means you get 150 watts x 4 = 600 watts peak envolope power at the most, safely, using this amplifier in the AM mode, not the 1kw it is rated for in SSB.
The other part of all this is total conversion efficiency.
At 600 watts 'peak' output and assming 50% efficiency, the total 'peak power' DC input would be close to 1200 watts DC.
On SSB, at 1kw output, the DC power input is about 2000 watts on speech peaks.
To further back this up; at 240 volts ac line input, the line is fused at 10 amps. 240vac x 10 amps is 2400 watts or at 120 vac the fuseing is at 20 amps. Both are a 2400 watt rateing so there is some capacity to spare without blowing fuses on speech peaks at full drive limits.
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As to one type of power being louder than another, please show this in any power formula if anyone thinks there is!
It does not exist either technically or by ear on an equal set of test parameters between the two types of circuits driven to the same percentage of modulation and power.
Most humans cannot tell a difference/change in audio level of less than 3db because the human ear loudness perception works on an a compressed or nonlinear scale up or down in volume.
For example, volume controls in many audio applications have what is known as an 'audio' taper resistance change as they are turned to better match the human hearing response to loudness changes.
These things cannot be talked about so simply by the uniformed let alone passed from one to another as incorrect hear-sey..
If referencing an AL80 amplifier; it is only an amplifier not a plate modulated stage.
In cathode drive, the driving power minus losses is passes on through and adds to the 'amplified signal' developed from grid modulating current flow from the DC power supplied to the tube.
.
For AM use with this amplifier, you can only run this amplifier to about 150 watts of carrier and talk for short periods of time without overdissapating the tube's plate.
Why: 3000 volts times .150 amp = 450 watts DC 'carrier' power. The tube's plate dissapation is not rated for much more than this.
When the modulated drive signal increases with speech, the average tube dissapation goes up greatly and begins to 'average shift' to higher plate temperatures as seen by the plate continuing to get brighter and brighter with key down time and no chance to cool.
This means you get 150 watts x 4 = 600 watts peak envolope power at the most, safely, using this amplifier in the AM mode, not the 1kw it is rated for in SSB.
The other part of all this is total conversion efficiency.
At 600 watts 'peak' output and assming 50% efficiency, the total 'peak power' DC input would be close to 1200 watts DC.
On SSB, at 1kw output, the DC power input is about 2000 watts on speech peaks.
To further back this up; at 240 volts ac line input, the line is fused at 10 amps. 240vac x 10 amps is 2400 watts or at 120 vac the fuseing is at 20 amps. Both are a 2400 watt rateing so there is some capacity to spare without blowing fuses on speech peaks at full drive limits.
.
As to one type of power being louder than another, please show this in any power formula if anyone thinks there is!
It does not exist either technically or by ear on an equal set of test parameters between the two types of circuits driven to the same percentage of modulation and power.
Most humans cannot tell a difference/change in audio level of less than 3db because the human ear loudness perception works on an a compressed or nonlinear scale up or down in volume.
For example, volume controls in many audio applications have what is known as an 'audio' taper resistance change as they are turned to better match the human hearing response to loudness changes.
These things cannot be talked about so simply by the uniformed let alone passed from one to another as incorrect hear-sey..
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