The design of the MDK is interesting.

- There are 2 sets of Potentiometers. This allows the DME to compare one with the other to create a fail-safe system.
- Within each set, one potentiometer is biased the opposite to the other. This allows for mathematical checks within the potentiometer set. More fail-safe features.
- All connections within the potentiometer sets are available to the DME. This allows for mathematical checks between the potentiometer set. Yet more fail-safe features.
- The potentiometers within a set are connected in parallel. From the test results we can conclude that the individual potentiometers have the same resistance, that is twice the resistance of the paralleled pair, so that is 2,000 ohms.
- The test results show that the minimum resistance on each potentiometer is 1,000 ohms.
- This makes sense. Engineers like using easy numbers, so a 2,000 ohm Potentiometer with a 1,000 ohm minimum reading, gives a 1,000 ohm range for 100% travel, or 10 ohms per every 1% of travel.
- The potentiometer supply is 5V. This means that the maximum current draw is 5/1,000 = 5mA and the minimum current draw is 5/2,000 = 2.5mA on any leg of the system.
- We test for resistance but the DME measures Voltage.

We do know that the MDK has problems with poor electrical connections. The added resistance upsetting the checks and balances (fail-safe) that the DME does.

If you look at it from a resistance perspective, you get these results. This shows that your MDK is out of spec.

Remember that this is a test sample of

**1**and we are trying to do something new and different. We could be doing this all wrong.