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Chapter 7: Troubleshooting
7. Troubleshooting
7.1 Common Questions
Q:
My TV doesn’t have an RCA jack (composite video connector). How can I
connect the PC to the converter?
A:
Connect through your VCR as follows:
1.Connect the VGA to Video Portable according to the connection
diagram shown on page 7; however, connect the composite video
cable to the Video In RCA jack on the VCR.
2.Power on the VCR and TV.
Switch the TV to the channel that
takes VCR input. Play a tape for a moment on the VCR to make sure
you can see the program on the TV screen; then remove the tape
from the VCR.
3.Set the VCR to Video Mode (a VCR generally has three input
sources: Video, TV, and Tape).
4.On your computer, type “
BBOX
” to invoke the VGA to Video
Portable driver and switch to TV display. If you can’t get a stable
display, adjust the screen synchronization with the hotkeys as
described in
Section 4.2
.
Another option is the RF modulator method. An RF modulator can
convert a composite video signal to an RF signal which can be used as
antenna input (VHF/UHF) on the TV. You can get an RF modulator
at any electronics store.
Q:
Why does the TV screen only show a gray image?
A:
The chrominance of your VGA to Video Portable has run out of range.
This can be fixed by adjusting the signal. See
Section 5.1
. It’s possible,
however, that your TV’s video system and the PC to TV Converter are not
compatible (a NTSC TV with a PAL PC to TV Converter, for example).
Equipment must be compatible for the proper results to occur.
Q:
Why aren’t text and images displayed at the top of the screen?
A:
Overscan may be occurring in an NTSC system. This happens because
the VGA has more display lines than the TV can display. In general, a TV has
only 420 lines, whereas VGA has 480 lines in 640 x 480 mode. Images may be
out of range or truncated. Use the hotkeys (see
Section 4.2
) to adjust the
screen position.
Q:
Why does the display shrink in a PAL system?
A:
PAL systems have 625 scan lines. If your VGA card is set for a 640 x 480
display, there’s no problem. If the display is 200 lines (320 x 200), however,
the image will shrink.