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Vacuum tube monitor with 13LO3I CRT and sound

     This vacuum tube monitor was made by rebuilding the previous monitor. I used this 13 cm oscillographic screen in it, which, unlike previous CRT, has two anodes, so I had to add a 3.6 kV voltage multiplier for the second anode. Monitor has also added the audio amplifier with the vacuum tube PCL82. As a temporary output transformer served useless 120V / 6V transformer. The last change is the modification of the modulation to the cathode. Sharpness of the CRT beam is surprisingly good, about 0.15 to 0.25 mm diameter. After changing the frequency of the deflection and using a long persistance CRT the monitor could also be used for receiving of SSTV (Slow TV). The advantage of electrostatic deflection is frequency independency.

     Warning! There's high voltage in this device! Prior to manipulation, it is always necessary to disconnect it from the network and make sure that the capacitors are discharged. The CRT tube can implode. You do everything on your own risk.

The schematic of Vacuum tube monitor with 13LO3I CRT and sound (click to enlarge). All capacitors are 400V unless otherwise noted.

televizní obraz na oscilografické obrazovce
The TV picture on a scope CRT :)

The homemade system with 5 vacuum tubes.

Controll panel.

Caution! This is an example of how the CRT should NEVER be mounted. In any case, do not try this!

Vacuum tube scope displays the the sawtooth at the deflection plates

Video - test of the Vacuum tube monitor with 13LO3I CRT and sound