Instruction for the Tube Tester Type W 19

It may happen that on a test card two different sockets are marked, That means that the tube is available in both ways, as for instance on test card no. 1, for tube KL1, which is available with European and prongless socket. Even then no error is possible since the tube will fit into only one of the two tube holders.

2. Turn Test Switch through all Positions,
Look for Shorts
and in position 12 make the Measurement.

In the starting position ,Aus“ the tester is switched off. Beginning with position 2 it is switched on, this can be seen by the light of the voltage regulator tube beneath the control window. Then, the test switch ist turned slowly from position to position. In position 2 the filament is tested while in positions 3 to 10 shorts are shown. If there is a short the meter pointer is deflected to the left side, i. e. it point to the letter „F“ = Fault in the outlined part of the scale.

In each position the switch is stopped by a notch, and only the indication in this fixed position is valid. If, while the switch is turned from one position to the next, the meter shows a short deflection or if it is deflected a little to the right, it does not mean anything.

If for instance in position 9 the meter pointer moves to the range marked by „F“ it indicates that there is a short between grid and plate, i. e. the tube cannot be used.

In positions 3 to 10 the meter indicates even as high a leakage as 200,000 ohms (at the edger of the outlined part of the scale). Tubes which have such a fault are already bad, because they would cause noise and distortion.

Summarizing the instruction given so far we may say: The test switch is turned slowly from position 1 to 10 and the meter pointer is watched to see that it is not deflected to the left. As soon as there is a „F“ indication the test is finished because the tube has a short then. The same is true if the pointer just