Homemade Scope Clock DG7 tube and PIC16F876

Powersupply and CRT deflection and microcontroller test circuit.
I was lucky to purcase two used but working DG7 tubes and a transformator cheap, one from Mullard and one from Phillips.
Other CRT Cathode Ray Tube types can be used, you can even rip one from an old and maybe dead oscilloscope,
then you also get the powersupply and stuff, if you are lucky the deflection amplifiers also work 🙂
Then your own home made Scope Clock is soon up and running, good luck.

Scope Clock

Here is the complete scope clock Powersupply schematic and PCB layout. Board with parts.
This powersupply uses an old tube gear transformator, so series resistors was used to make all the different voltages.
Voltages written on the schematic are optimal values for a DG7-32 CRT.. but other tubes can also be used, read below.
Download PSU PCB layout for easy homemade Height = 105mm, Width = 85mm.

Powersupply using special made transformator, using no series resistors:
See schematic the huge capacitors can be changed !
New Powersupply board first test of transformator
New special trafo close up picture.
Trafo in hand see the small size.

This is the schematic over the blanking circuit, and PCB layout over Deflection and blanking circuit.
Baord with parts and here also
Download Deflection PCB layout for easy homemade Height = 50.8mm, Width = 111.7mm

PIC16F876 board schematic, using ZN508 DAC download and print out (updated May 2003)
PIC16F876 board schematic, using AD7302 DAC download and print out (updated Okt 2005)
See a closeup of my PIC16 demo board this board was easy to change into a scope clock controller.
I use an old ZN508 dual 8 bit parallel input DAC (see glitches), if you want a little bit better picture I suggest you use AD7302 or DAC8229 or AD5332.
If your scope tube is small or maybe a little bit out of focus, you will not notice the glitches.

 

For more detail: Homemade Scope Clock DG7 tube and PIC16F876

About The Author

Ibrar Ayyub

I am an experienced technical writer holding a Master's degree in computer science from BZU Multan, Pakistan University. With a background spanning various industries, particularly in home automation and engineering, I have honed my skills in crafting clear and concise content. Proficient in leveraging infographics and diagrams, I strive to simplify complex concepts for readers. My strength lies in thorough research and presenting information in a structured and logical format.

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