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[email protected] stratus46@yahoo.com is offline
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Default Composite video from Compaq Armada e500.

On Sep 14, 7:31*am, Peter Easthope wrote:
On Sep 9, 8:32*pm, wrote:

I hunted up the Compaq Armada docs from HP and they are not

really
clear on the TV output. They say the unit puts out composite TV.


Yes.

Here is a link to a Tektronix page showing SMPTE NTSC color bars

on a
waveform scope. The amplitude is 1 Volt p-p into a 75 Ohm

termination.
Amplitude is typically 2 Volts without the termination. Bandwidth

is
4.5 MHz for standard def. Line length from H sync to H sync 63.56

uS

Thanks. *I have only a plain old BK Precision 2522 Digital Storage
Oscilloscope.
No waveform monitor. *The photos I posted are just the raw video

going
to the
BK 2522. *Without the demodulation capability of a waveform

monitor,
an
oscilloscope can not display color bars. *The BK 2522 might do a
little more
in this case but I have yet to learn the skills.

Thanks, * * * * * * * * * * * *... Peter E.


A waveform monitor is nothing more than a specialized scope with
preselected gains and sweep rates and a graticle in IRE units
vertically and uS horizontally rather than cm.. Your scope (and my old
Tek 475) will be just fine. I wanted you to see what the video
waveform should look like and Tektronix has excellent info on TV. The
vector scope is a different animal and is not needed for now but by
probing the chroma demodulators in a monitor could you display vectors
on your scope as well.

Bottom line: if you displayed color bars on the Compaq the scope photo
from Tek will be close to what you see on your scope once you get the
sweep and gains set up. The trickiest part of TV is triggering the
scope but many scopes have a TV mode to make it easier.

G