Oscilloscope with LCD monitor display...

[Externet]

How simple can it be designed/done ? What would it take ?
A single channel, 100KHz bandwidth, no storage, VGA output for that spare old monitor sitting behind the spider webs...

Or has it been done and there is instructions on the net ? Or such does exist in kit form ? There is many cheap oscilloscope kits but for smaller LCD displays.

 

[Externet]

Replacing oscilloscope CRT with LCD ?

Hi.
A few vendors offer kits, custom for specific equipment, sometimes costlier than the oscilloscope...

With so many junked video displays like dvd players and removed from automobiles head rests found at pawn shops... How simple could a transplant/adaptation be ? What would it take to come up with a generic design adaptable to your oscilloscope ?
It would make the unit much lighter, simpler and reliable power supply and CRT circuitry...

 

[Externet]

Oscilloscope with NTSC video output ?

How to implement composite video output to an oscilloscope ?

There are NTSC generator chips, but the vertical and horizontal deflection signals in an oscilloscope are very different from video. Is conversion possible ? Where to learn how has it been done ?

 

[FvM]

Circuit of LCD oscilloscopes is completely different from classical (analog) CRO, you won't keep much of the original CRO circuit when converting it to LCD display. Need to add at least ADC and digital signal storage which isn't present in analog oscilloscope, at the same time trash the horizontal deflection and trigger circuit, vertical output amplifier, high voltage CRT supply.

 

[Externet]

Thanks.
Am sorry the two posts were merged. The first post is related to design an oscilloscope circuit to be used with a commercial VGA computer monitor as display.

The second post is related to modernization / repair / replacement of the built-in CRT in an oscilloscope with a LCD module, not a computer monitor.

 

[FvM]

Oscilloscopes with video (NTSC, VGA or whatever) output are digital oscilloscopes, quite similar to oscilloscopes with LCD display.

The display is generated out of a frame memory, similar to the image of computer monitor. The video signal timing is completely independent of recorded oscilloscope signal.

- - - Updated - - -

Am sorry the two posts were merged. The first post is related to design an oscilloscope circuit to be used with a commercial VGA computer monitor as display.

The second post is related to modernization / repair / replacement of the built-in CRT in an oscilloscope with a LCD module, not a computer monitor.

If you understand the technique behind both designs, you'll see how closely related they are.

 

[Warpspeed]

How simple can it be designed/done ? What would it take ?
A single channel, 100KHz bandwidth, no storage, VGA output for that spare old monitor sitting behind the spider webs...

Or has it been done and there is instructions on the net ? Or such does exist in kit form ? There is many cheap oscilloscope kits but for smaller LCD displays.

Just taking the VGA display part of it. That in itself is a fairly major project if you decide to use common small TTL/CMOS chip types. Its practical only for very low resolution bar graph displays or similar.
I fairly recently completed a project like that myself.

As soon as you start needing speed and higher resolution, a proper commercial video generator chip (and a large amount of RAM) is the only practical way.
It will be surface mount with a huge number of pins, and require rather complex software initialisation of all the internal functions.
You might as well recycle a whole plug in video board from an older PC.
That is impractical too, unless you use the whole PC motherboard with it.
Then you might as well just use a whole PC and plug a commercial USB digital oscilloscope into it.

Its not really a practical project unless your requirements are very simple.
My own project was just to display 30 vertical bars to display the cell voltages of a 30 cell battery. Just the VGA generator required twenty chips to convert the output of a 2K dual port ram into VGA.