
Oscilloscope Video Monitor (2011) - brudgers
http://tubetime.us/index.php/2011/03/29/oscilloscope-video-monitor/
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StringyBob
I remember making something with the LM1881 chip used here to remove copy
protection from analogue composite video signals. Needed so VHS videos you
bought played properly on my TV! Some things never change...

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DanBC
Here's one example of that.
[http://www.kolumbus.fi/pami1/macrovision/](http://www.kolumbus.fi/pami1/macrovision/)

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masswerk
The video on YouTube (no Flash):

[https://www.youtube.com/watch?v=-FK7hy5usYE](https://www.youtube.com/watch?v=-FK7hy5usYE)

(I also found this similar one,
[https://www.youtube.com/watch?v=5FYF5uhCzAM](https://www.youtube.com/watch?v=5FYF5uhCzAM))

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NikkiA
Well, yes, a crt oscilloscope in X-Y mode is just a crt monochrome television
without sync generation and a fixed brightness. Back in the early days many
people used to make their own oscilloscopes from 'cheap' TV tubes (only
downside usually being that a TV tube had less phosphor than an oscilloscope
really needed).

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mannykannot
Does a TV tube's use of magnetic scanning not present a considerable
difficulty in using them in an oscilloscope? IIRC, a CRT television typically
used some rather hackish special-purpose circuitry to linearize its horizontal
and vertical scanning, each just at one specific frequency?

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sannee
The build I have seen was driving the electromagnetic steering coils directly,
bypassing any original TV circuitry.

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mannykannot
I imagine so, but you still have to deal with the underlying problem -- the
coils are an inductive load -- and not just at one scan rate, but over all the
scan rates you are using and at all frequencies in the signals you are
displaying.

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morkzid
Wow, the ramp circuit is so simple!

