* It generates "THE QUICK BROWN FOX JUMPED OVER THE LAZY DOGS BACK"
message.
* It can generate alternating two-character patterns such as RY.
* It has the ability to introduce distortion of the Baudot signal.
* It can test different line speeds depending on what gear set is
installed.
When you power it on, a front-panel disk spins. This disk has an
opening to view a neon bulb. Surrounding the spinning disk is a stationary
scale with start, data and stop bits. As distortion is introduced
to the test signal, the position of the hole in the spinning disk changes
relative to the fixed outer ring and the neon lamp flashes.
The offset from where the neon lamp is, versus normal, is proportionate
to the amount of distortion present. With the distortion test, one
can tell how well the “mechanics ” are operating in a teleprinter. Tolerance
to a lot of distortion indicates good mechanics.
 |
| DXD200 Distortion Test Set. Although not fitted when the ship was in service, this DXD200 example is held by the Tribal class destroyer HMCS HAIDA. It is used to test the Teletype equipment in the ship's Message Centre. (Photo by Jerry Proc) |
The DXD400 was the ASCII version of the test set.