Black Box AC076A User manual

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SUPPORT
INFORMATION
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Mail order: Black Box Corporation, 1000 Park Drive, Lawrence, PA 15055-1018
Web site: www.blackbox.com • E-mail: [email protected]
AUGUST 2000
AC076A
Video Converter Pro for Mac
Video Converter Pro for Mac
UNDERSCAN
NORMAL
FL ICKER REDUCTION
NORMAL
FREEZE IMAGE
NORMAL
POWER
LOCK

1
FEDERAL COMMUNICATIONS COMMISSION
AND
INDUSTRY CANADA
RADIO FREQUENCY INTERFERENCE STATEMENTS
This equipment generates, uses, and can radiate radio frequency energy
and if not installed and used properly, that is, in strict accordance with the
manufacturer’s instructions, may cause interference to radio communication.
It has been tested and found to comply with the limits for a Class A
computing device in accordance with the specifications in Subpart J
of Part 15 of FCC rules, which are designed to provide reasonable protection
against such interference when the equipment is operated in a commercial
environment. Operation of this equipment in a residential area is likely to
cause interference, in which case the user at his own expense will be required
to take whatever measures may be necessary to correct the interference.
Changes or modifications not expressly approved by the party responsible
for compliance could void the user’s authority to operate the equipment.
This digital apparatus does not exceed the Class A limits for radio noise emission from
digital apparatus set out in the Radio Interference Regulation of Industry Canada.
Le présent appareil numérique n’émet pas de bruits radioélectriques dépassant les limites
applicables aux appareils numériques declasse A prescrites dans le Règlement sur le
brouillage radioélectrique publié par Industrie Canada.
TRADEMARKS
Black Box and the logo are registered trademarks of Black Box
Corporation.
Mac and Macintosh are registered trademarks of Apple Computer, Inc.
RCA is a registered trademark of General Electric Co.
Any other trademarks mentioned in this manual are acknowledged to be the property
of the trademark owners.
FCC AND IC STATEMENTS, TRADEMARKS

2
VIDEO CONVERTER PRO FOR MAC

3
VIDEO CONVERTER PRO FOR MAC
Table of Contents
Chapter Page
1. Specifications .......................................................................................... 3
2. Introduction ........................................................................................... 4
3. Installation .............................................................................................. 5
3.1 Initial Steps ...................................................................................... 5
3.2 Hooking Up Video Output ............................................................. 5
3.3 Selecting Your Video Standard ....................................................... 6
3.4 Booting your Converter System ....................................................... 6
4. Operation ............................................................................................... 7
4.1 Indicators ......................................................................................... 7
4.2 Front-Panel Controlss ....................................................................... 7
4.3 Other Features ................................................................................. 8
5. What to Expect from Converted Computer Images ............................ 9
6. Troubleshooting ................................................................................... 11
Appendix A: S-Video, the Improved Quality Video Standard ................... 12
Appendix B: Connector Pinouts ................................................................. 13

4
CHAPTER 1: Specifications
Macintosh Video
Input Standards — Mac 512 x 384 resolution at 24 KHz or 640 x 480
resolution at 35.5 KHz, up to 24-bit color
Video Output Standards — Mac; NTSC or PAL: Composite video,
S-Video, RGBS
Controls — (4) External: (1) rear-mounted slide switch:
NTSC/PAL; (3) front-mounted toggle switches:
Underscan, Flicker Reduction, Freeze Image
Indicators — LEDs: (1) Power, (1) Lock
Connectors — (1) Mac Input (“VIDEO IN”): DB15HD
female; (4) Video Output: Mac (“VIDEO
OUT,” DB15HD female); NTSC/PAL:
Composite (“VIDEO,” RCA®phono jack),
S-Video (“S-VIDEO,” DIN female), RGBS
(“RGB/EXPANSION,” DB26HD female)
Power — From desktop power supply:
Input range: 95-250-VAC, 47-63 Hz
(autosensing) at 0.9 A;
Output: 5 VDC at 3.8 A
Size — 1.5"H x 7.25"W x 6.25"D (3.8 x 18.5 x 15.9 cm)
Weight — 2.9 lb. (1.3 kg)
1. Specifications

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VIDEO CONVERTER PRO FOR MAC
The Video Converter Pro for Mac®
converts your computer’s monitor
signal into a form suitable for
recording on a VCR, displaying
on a conventional TV or video
monitor, or integrating into a multi-
media production system. No soft-
ware is required to operate the
Converter, and you won’t have to
install any boards in your computer.
Chapters 3 and 4of this manual
show you how to install and operate
your Converter. Chapter 5 gives you
some guidelines on what you should
(and shouldn’t) expect from your
converted computer images and
explains how to get the best quality
of image display. Chapter 6 gives you
tips for handling problems that
might occur with your Coverter
system. Appendix A explains what
S-Video is and why it should be used
as output from your Converter
whenever possible. Lastly, Appendix
B shows the pinouts of all of your
Converter’s connectors.
2. Introduction

6
CHAPTER 3: Installation
Follow the procedure outlined below
to install your Video Converter Pro
for Mac.
3.1 Initial Steps
1. Disconnect your monitor from
the monitor port on your Mac.
2. Connect one end of the 6-foot
cable provided with the
Converter to the monitor port
on your computer. Plug the
other end into the connector on
the rear panel of the Converter
labeled VIDEO IN. See Figure 3-1.
3. If you want your monitor to
continue to display, connect it
to the output connector labeled
VIDEO OUT. See below for a
description of this output.
4. Connect the power supply
provided with the Converter to
the connector labeled POWER.
Plug the AC-line cord into an
outlet to provide power to the
Converter. (If you ever need an
AC-line cord specific to another
country, call our sales office in
that country.)
3.2 Hooking Up Video Output
Now connect one or more of the
Converter’s four output ports to
your video equipment:
VIDEO OUT: This output is a
passthrough of the MAC IN input.
You can connect a standard computer
monitor (or a multi-sync monitor
if your system supports these) to
this output.
VIDEO: Feed this single
composite-video output signal into
the “video” input jacks on ordinary
TVs, monitors, VCRs, or professional
video equipment by using the
included composite-video cable.
This signal can’t be fed into a TV’s
or VCR’s “antenna” input.
S-VIDEO: Called S-Video, S-VHS,
or Y/C, this output is an advanced
form of video which carries the
brightness and color parts of
images on two separate signals.
It is compatible with the Hi-8 and
Beta-ED standards. Feed it into
compatible equipment by using
the included S-video cable and you’ll
get a better-quality picture than the
VIDEO output can provide.
RGB/EXPANSION: This premium-
quality output, which can be used by
some video projectors and monitors,
consists of separate red, green, blue,
and sync signals. (These signals might
also be used by expansion accessories
in the future.) Feed it into compatible
equipment by using our optional
RGBS cable with BNC connectors.
3. Installation

7
VIDEO CONVERTER PRO FOR MAC
Call us for a quote if you’d like
RGBS cable with European SCART
connectors or connectors for
Sharp LCD projectors.
3.3 Selecting Your Video Standard
Use the NTSC/PAL slide switch on
the back of your Converter to choose
which standard you’ll use for the
VIDEO, S-VIDEO, and RGB outputs.
NTSC is the video standard for the
USA, Canada, Mexico, Japan, and
parts of South America. PAL is used
throughout most of Europe, the
Middle East, Southern Asia, and
the Pacific Rim.
3.4 Booting Your Converter System
If you haven’t already done so, plug
in and turn on your computer. The
green indicator labeled LOCK on the
Converter’s front panel should light,
showing that the Converter is
receiving a proper signal from the
computer. (Refer to the next chapter
for an explanation of this indicator.)
Make sure the FREEZE IMAGE
switch on the front panel is in the
NORMAL position, so that your
computer-image sequences will
flow smoothly.
Your Video Converter Pro for Mac
is now ready for normal operation.
Operating your Video Converter Pro
for Mac is very simple. There are few
controls to adjust and no hidden
DIP switches to set. Figure 4-1, below,
shows the front panel with its switches
and indicators.
OUTPUTS NTSC PAL
VIDEO OUTS-VIDEO VIDEORGB/EXPANSION VIDEO IN POWER
Figure 3-1. Rear panel of a Video Converter Pro for Mac.
NOTE: All outputs are available at the same time. Unused outputs
do not have to be terminated if they are not being used.
Highest quality RGBS
at 15.75 kHz (also
future expansion)
S-Video for separate,
clearer Y/C video signals
Baseband video signal
for standard video
equipment
NTSC/PAL switch for
selecting the appropriate
video standard
Buffered Macintosh
video signal for
local Mac monitor
Macintosh video
signal input from
computer
Power supply
(line cord from
transformer plugs
in here)

8
CHAPTER 4: Operation
4.1 Indicators
The red POWER indicator lights
up when your Converter is receiving
DC power. If this light is glowing
dimly or not at all, there might be
something wrong with the external
power supply. See Chapter 6.
The green LOCK indicator lights
up when the Converter is receiving
a valid computer signal through the
VIDEO IN connector on its rear
panel. Both the 512 x 384 and
640 x 480 Macintosh®video-display
modes are supported. Which one
the Converter will use depends on
the monitor attached to the VIDEO
OUT port (see Section 4.3).
4.2 Front-Panel Controls
UNDERSCAN: When this switch is in
the NORMAL position, images that
the Coverter outputs in Composite,
S-Video, and RGBS formats will fill
the entire viewable screen area. But
because some monitors “overscan”
their screens, some desirable parts of
your images could be cropped off of
the screen. If this is the case, flip this
switch to the UNDERSCAN position
to shrink the images, both
horizontally and vertically,
approximately 10% in size.
4. Operation
Figure 4-1. Front panel of a Video Converter Pro for Mac.
LOCK UNDERSCAN FLICKER REDUCTION FREEZE IMAGE
NORMALNORMALNORMALPOWER
Receiving power
when POWER is
lit. Mac signal is
OK at input
when LOCK is lit
Image is “shrunk” in both
the horizontal and vertical
directions when switch is in
UNDERSCAN position
Anti-flicker filter is
active when switch is in
FLICKER REDUCTION
position
Image is instantly
“frozen” when switch is
in FREEZE IMAGE
position

9
VIDEO CONVERTER PRO FOR MAC
FLICKER REDUCTION: When
this switch is in the NORMAL
position, the Converter sends images
using fully interlaced Composite,
S-Video, and RGBS video signals.
However, thin horizontal lines in
the images might appear to “flicker”
on and off at a very fast rate. This
annoying flicker, if present, can be
virtually eliminated by setting this
switch to the FLICKER REDUCTION
position. There is a tradeoff with
this feature: you might notice a
slight loss of vertical resolution,
detail, or brightness.
FREEZE IMAGE: You might
want to freeze a frame of an image
sequence on the screen without
having to mess around with your
software. If this switch is moved to
the FREEZE IMAGE position, the
image on the Composite, S-Video,
and RGBS outputs is frozen. It will
remain frozen until you move the
switch back to the NORMAL
position, at which time whatever
image is currently being received
through VIDEO IN will be displayed.
4.3 Other Features
• If the computer input signal is
no longer present on VIDEO IN
because the computer has been
turned off or the input cable has
been disconnected, the image
will automatically “freeze” and
the LOCK indicator will go off.
• The VIDEO OUT output will
always display what is present on
the VIDEO IN input regardless
of the “display mode” the
computer may be in. If VIDEO
IN is at 1024 x 768 resolution,
VIDEO OUT will also be
1024 x 768. This is not true of the
Composite, S-Video, and RGBS
outputs: images in Macintosh
modes beyond 640 x 480 lines
will appear scrambled and out
of sync when translated into
these formats.
• The Converter supports both
the low-res 512 x 384 and hi-res
640 x 480 Mac modes. Some Mac
models will boot in one mode or
the other depending on the type
of monitor they are connected
to. The Converter makes use
of this capability: if a low-res
monitor is connected to its
VIDEO OUT output, it will
force the Macintosh to boot in
512 x 384 mode, but if a hi-res
monitor (or no monitor) is
connected, it will force 640 x 480.

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CHAPTER 5: What to Expect from Converted Computer Images
We have included this section to give
you some insight into what you can
and should expect computer images
to look like once they are converted
to standard video. People are some-
times surprised that computer
images converted to video do not
look as sharp and vivid as they do
on the computer monitor. Although
this may be somewhat disappointing,
it should come as no surprise.
Color TV and video monitors, and
the conventional video standards
they use (NTSC and PAL), have
been with us since the 1940’s
and 50’s. When high-resolution
computer-graphics standards such
as Mac II were introduced less than
a decade ago, new display techno-
logies had been developed to
achieve higher detail and sharper
colors. But, although many design
improvements have been made to
TV monitors and VCRs, they are still
limited to basic technologies that are
40 years old.
Scan converters like the Video
Converter Pro for Mac were created
to bridge the gap between the
dissimilar standards of computer
video and conventional video
equipment. They work, but the
trade-off in the process is that you
are taking computer images whose
sharpness and detail are clearly
visible on today’s monitors and
displaying them on TVs, or recording
them on VCRs, that can’t do them
justice. But all is not lost. There are a
few things you can do to get the best
image possible on your TV/monitor
or recorded on video tape. The tips
that follow will all contribute to
improved quality of your display
and/or VCR recording.
• In the world of video, black,
white, and all the shades of gray
are not processed the same way
as “real colors.” TVs and VCRs
process these shades with a
minimum of distortion. When
it’s possible, consider using
grayscale images, because
they’ll be much sharper than
the equivalent colored images.
• The “Christmas Effect” occurs
with computer images created
by artists who really like the green
and red color combination.
Nothing looks worse on a TV.
Try to avoid saturated colors.
• Sometimes graphics look so
impressive on a computer
monitor that users assume that
the process of conversion to TV
can’t possibly make the graphics
look bad. However, what TVs will
actually show, especially if they
are displaying a video signal that
was “beat up” by a VCR recording,
can be ugly. To avoid such nasty
surprises, connect a Converter
and TV to your computer and
view your “televised” graphics
while you create them, before you
present them.
5. What to Expect from Converted
Computer Images

11
VIDEO CONVERTER PRO FOR MAC
• When you make VCR recordings,
use either (1) a “Pro” or
“Broadcast” grade, name-brand
tape, or (2) an S-VHS (Super-
VHS) tape (these will play in
standard VHS machines). Also,
record using the fastest speed
(the speed corresponding to the
shortest total time per tape—
2 hours on a T-120 cassette).
You will have less noise and
tape jitter in your recording.
• Almost all TVs and video
monitors overscan images,
resulting in some of the picture
being “cropped” off the edges
of the picture tube. The
Converter’s UNDERSCAN mode
will shrink images to compensate
for this overscan, which will vary
in amount from one TV or
monitor to another. To ensure
that the useful parts of your
images are visible on TVs and
monitors, keep all text and other
informational content at least
5% in from the sides, top
and bottom.
• By far the most annoying effect
that occurs when a computer
image is converted to video is
“flicker.” This rapid flashing of
images’ brightness can appear
to be pervasive throughout the
screen or localized to one
particular area. It is most
noticeable on thin horizontal
lines, particularly on bright lines
against a dark background. It is
not seen on computer monitors
because all the horizontal lines
that make up the image are
drawn on the screen in one pass
from top to bottom, 60 or 70
times a second. When the same
image is converted to video, a
single line will only be drawn on
the screen either 30 (NTSC) or
25 (PAL) times a second. This
rate is not rapid enough to make
your brain register each drawing
of the line as the same continuous
line, so the line appears to
flicker. The anti-flicker filter
in your Video Converter Pro
for Mac employs an advanced
design technique to overcome
this problem with only a very
slight loss in vertical detail.

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CHAPTER 6: Troubleshooting
This chapter lists some concerns that
commonly arise during operation af
the Video Converter Pro for Mac, as
well as some possible causes and
remedies.
Nothing works or no computer
output.
1. Is the power supply connected
and plugged into the AC wall outlet?
Check the red POWER LED. If it’s
on, go to Step 2.
2. Is the wiring from your Mac to the
Converter and from the Converter
to your video equipment properly
connected? If it is, go to Step 3.
3. Is the computer sending out a
proper Macintosh video signal?
Check the green LOCK LED. If it’s
on, try replacing the Converter’s
connection to your computer with a
direct connection to a Mac monitor.
If the monitor’s display looks OK,
call us.
No video outputs.
1. Is the FREEZE IMAGE switch in
the FREEZE IMAGE position? If not,
go to Step 2.
2. Is your video equipment in the
proper mode to accept direct video
input? If it is, go to Step 3.
3. Is the computer sending out a
proper Macintosh video signal?
Check the green LOCK LED. If it’s
on, try replacing the Converter’s
connection to your computer with a
direct connection to a Mac monitor.
If the monitor’s display looks OK,
call us.
Some of the image is being lost off
the sides or top and bottom.
Is the UNDERSCAN switch in the
NORMAL position? If not, or if
moving it doesn’t help, then your
TV or monitor has an excessive
amount of overscan. If possible, try a
different TV or monitor. If this can’t
be done or still doesn’t help, call us.
6. Troubleshooting

13
VIDEO CONVERTER PRO FOR MAC
Most of us are familiar with two
forms of TV video: (1) “RF,” which
is how broadcast and cable TV comes
into our homes, and (2) “Composite
Video,” “Baseband Video,” or just
plain “Video,” which is a single
electrical signal (made up of
brightness, color, and synchronizing
components) used by most VCRs.
A problem arises when your TV,
monitor, or VCR has to break either
of these signals apart to show it on
the screen or record it on tape. A
lot of processing is involved and
distortions of the image occur.
Several years ago, TV engineers
devised a simple scheme which was
not only relatively inexpensive to
implement but very effective in
reducing these distortions. It is
called “S-Video,” and can be used
with your Video Converter Pro
for Mac.
In this TV-signal system, there
are actually two signals. The
“LUMINANCE” (“Y”) signal carries
the sync and brightness components
of the picture, while the
“CHROMINANCE” (“CHROMA”
or “C”) signal carries the color
component. By feeding these two
signals into your video equipment
separately, S-Video eliminates the
need for the equipment to do the
work of separating the signals
internally. The result is a displayed
image that has more detail and less
color distortion. If you were to
compare two otherwise identical
images, one displayed using Video
mode and the other using S-Video,
the difference in the quality of the
images would be dramatic.
Almost all of the new larger-screen
TVs that have audio/video jacks also
have an S-Video jack just like the one
on the rear of your Converter. If it is
available, use it! You will see a
difference.
Appendix A: S-Video, the Improved
Quality Video Standard

14
APPENDIX B: Connector Pinouts
POWER
Center +5 VDC In
Outer Ground
VIDEO IN
1 Red
2 Green
3 Blue
4 ID Bit LO-Res Out
5 Ground
6 Red Ground
7 Green Ground
8 Blue Ground
10 Ground
11 Ground
13 Comp Sync In
14 V-Sync In
15 H-Sync In
MAC OUTPUT (“VIDEO OUT”)
1 Red
2 Green
3 Blue
5 Ground
6 Red Ground
7 Green Ground
8 Blue Ground
9 ID Bit LO-Res In
10 Ground
12 N/C
13 Comp Sync Out
14 V-Sync Out
15 H-Sync Out
COMPOSITE VIDEO OUTPUT
(“VIDEO”)
Center Video Out
Outer Video Ground
S-VIDEO OUTPUT
1 Ground
2 Ground
3 Luminance
4 Chrominance
RGBS OUTPUT
(“RGB/EXPANSION”)
1 Ground
2 Ground
3 Red
5 Green
7 Blue
15 Composite Sync
Appendix B: Connector Pinouts

1000 Park Drive • Lawrence, PA 15055-1018 • 724-746-5500 • Fax [phone]
© Copyright 2000. Black Box Corporation. All rights reserved.