After defining all circuit variables such as B+ voltage,  idle current, and plate load resistance, Tube CAD can search for gross error conditions and provide descriptions and remedies, which you may choose to accept.

Error List
The errors caught are of the gross kind-- excessive plate voltage, excessive plate dissipation, current--that could damage the tube or greatly compromise the circuits performance. Each line represents one type of error.

Error Description
When a line in the Error List box is selected, a description of that error is displayed below in the Error Description bracket. Each error gets its own explication.

Error Remedies
Each type of error finds its remedy displayed in the Error Remedies bracket. Not every solution need be tried, as a change in one the variables usually results in a change more than one operating parameter.

Make It So
Pressing the "Make it so" button will let Tube CAD correct the error conditions for you. It does this by auto-loading the circuit part values and operating points that will return the circuit to normal and eliminate the error conditions.