What effect is this c-battery, or grid-battery, going to have on the current in the plate circuit?
Choose your c-battery for amplification and not detection and try to receive.
Use the proper value of c-battery as determined from your study of the characteristic of the tube.
Usually, therefore, we arrange to shift the characteristic by using a c-battery.
As long as we do not use a higher voltage than 188that of the c-battery which is in the box no current can flow.