Among the equipment you should have at your station is the Oscilloscope.
 
 
 
So many people place too much importance on Watt meters. Though it is nice to know what your power is, it really means nothing unless it is backed up with the correct envelope growth.
 
 
 
In Amplitude Modulation, the span between the transmitter and the receiver is bridged with the carrier. The information that the receiver gets is actually the audio in the sidebands. That is the reason it is called "Amplitude" modulation, is because its is a CHANGE in amplitude that conveys the speech. The receiver does not "hear" the carrier.
 
 
 
Think of your amplifier as a bucket of water. If it is full, there is no room for any more change than from full to empty (That is 100% negative with no positive growth). Granted there is some change, and there will be some audio, but if the bucket was only 1/4 full, there would be a 100% positive change, and at the same time, there would be a 100% negative change.
 
 
 
This is the Minimum to shoot for.
 
 
 
If the carrier was to go down, and the peaks still the same without pinching the carrier, you would have asymmetrical modulation. That is useful up to about 150%. Your dead key should show a 2 box thick bar, and with audio, should grow to peaks of at least 4 boxes peak to peak for only 100%. You don't want to see the peaks pinch in the center, or become flat at the tops. If you are shooting for more than 100% Positive peaks, your carrier will have to come down. This may mean that your driver has to come down, and your peaks may not be as high as they were. This is a price that must be paid at times. Nothing good is free.
 
 
 
The most you can do here is your MAX no matter WATT the meter says.

The Oscilloscope and You

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