Using a TV with hijacked deflection coils

#1

OsciStudio Version:7.0
Operating System: windows 10

Hi Folks! So I have a few old TV’s that I’ve tried to turn into oscillographs. The concept is super simple take the two beam deflection coils, drive them with a signal and you have a diy oscillograph. now I figured that since coil A deflects the beam on the y axis and coil b deflects the x axis, I should be able to use oscistudio to draw pictures on them. so far not so good, I have signal, I’m able to drive the coils with osci but i have nothing close to the shapes I have loaded. has anyone successfully used anything other than the xy inputs on a regular oscilloscope? there has to be a way to achieve this. anyone have any suggestions? thanks folks!

#2

driving a TV is not super simple.

you will encounter a few issues:

  • magnetic deflection (TV) is very slow compared to electrostatic deflection (oscilloscopes)
  • coils for horizontal and vertical deflection are wound differently. because of this you will either have to accept different distortions in the x- and y-direction… or rewire the coils.
  • you want to use a current driver, not a voltage driver
  • take care of the DC component. it’s a bit of work to get this right throughout the entire pipeline.
  • if you disconnect the coils from the existing driver inside of the TV, then the electron gun might shut off too. to fix this you have to add some “pretend” coils, to work around the TV’s built in safety systems. seems to be fine in your case though.

did you google? there’s some info out there.

hope this helps.