The YS-150 Tuning Eye Demonstrator is a compact 'magic eye' tuning indicator tube driver circuit, which generates a bouncing visual effect on a compact eye tube. The YS-150 has two speed settings, slow-change RGB under-tube lighting, and perhaps the most unique of all, the YS-150 can be powered with a single 5VDC supply.
For this device to operate, the user must supply a 5VDC, 600ma supply to power the high voltage converter and drive circuitry. A common DC 'wall wart' power supply that outputs 5VDC can be bought from nearly any major retailer for less than $10, or the user may choose to use a battery power source. When making the power connections, be sure to observe correct polarity as indicated in the diagram below, as a reversed connection could damage the device.
YS-150, power connections.
Jumper Settings
The YS-150 has two speed settings, which can be selected by configuring the jumpers as indicated in the diagram below. If both jumpers are removed and rotated 90 degrees, the oscillator will be disconnected and the blades of the eye can be opened and closed by turning potentiometer R5 with a small screwdriver.
YS-150, jumper settings.
When the unit is oscillating, potentiometer R5 is used to set the midpoint of the blades so the tube will oscillate correctly. If the included tube is ever replaced with an EM84 from another manufacturer, potentiometer R5 should be turned counterclockwise as far as it will go with a small screwdriver, and then slowly increased until the tube begins to oscillate.
