IN-13 Bargraph Winker

Here is a winker circuit using a Russian IN-13 neon bar graph tube. Its a linear tube, so it works similar to a magic eye. With a magic eye the shadow varies with voltage. With this neon tube, the glow length varies with current. The circuit used is a low voltage phase shift oscillator using one general purpose PNP transistor. It feeds a High voltage NPN transistor that translates the sinewave voltage into a analogous current. High voltage (140V) is generated using a LM393 based switching supply.