When testing between the source and drain of an N channel JFET using the R x 100 range, what should the readings indicate?

When testing between the source and drain of an N channel JFET using the R x 100 range, what should the readings indicate?

• A. Variable in one direction
• B. Open in both directions
• C. Equal in both directions
• D. Short in both directions

Answer: (C)

When testing between the source and drain of an N-channel JFET using the R x 100 range, the correct readings should indicate equal resistance in both directions. This behavior is consistent with the characteristics of a JFET, which is designed to allow current flow from the drain to the source when the gate-source voltage is sufficiently negative, but does not conduct in the reverse direction due to the built-in potential barrier of the junctions. This leads to a symmetrical resistance reading when assessed with an ohmmeter, indicating that the device is not internally damaged or exhibiting abnormal behavior. In contrast, an open reading in both directions would suggest a failure in the JFET, as it indicates a lack of connectivity. A variable reading in one direction might suggest faulty behavior or a damaged component, which would not be typical for a properly functioning JFET. Likewise, a short in both directions would indicate that there is a direct electrical connection without any resistance, typically pointing to a faulty device that has failed completely. Thus, equal resistance readings confirm that the JFET structure is intact and functioning correctly within its operational parameters.

When testing between the source and drain of an N-channel JFET using the R x 100 range, the correct readings should indicate equal resistance in both directions. This behavior is consistent with the characteristics of a JFET, which is designed to allow current flow from the drain to the source when the gate-source voltage is sufficiently negative, but does not conduct in the reverse direction due to the built-in potential barrier of the junctions. This leads to a symmetrical resistance reading when assessed with an ohmmeter, indicating that the device is not internally damaged or exhibiting abnormal behavior.

In contrast, an open reading in both directions would suggest a failure in the JFET, as it indicates a lack of connectivity. A variable reading in one direction might suggest faulty behavior or a damaged component, which would not be typical for a properly functioning JFET. Likewise, a short in both directions would indicate that there is a direct electrical connection without any resistance, typically pointing to a faulty device that has failed completely. Thus, equal resistance readings confirm that the JFET structure is intact and functioning correctly within its operational parameters.