Additional Video Rack Notes
The purpose of the time base corrector (TBC) is to clean the video
signals coming off the 1/2" VHS decks (due to the playback speed not
precisely matching the recording speed). You can also adjust video
levels. It's critical to do this when recording 1/2" signal onto the
Abekas, and perhaps wise when recording to the other 1/2" deck or the
3/4" decks.
The input of the TBC is decided by the TBC/Scope Switch, and should
usually be the 1/2" left VHS deck. On the Editor switch you should
select TBC.
Here are some example configurations:
Record VHS (e.g, left VCR) to Abekas:
- Select 1/2" Left on the TBC/Scope Switch.
- Select TBC on the Editor Switch.
- Select NTSC Decoder on the RGB Record Switch.
- Select Abekas on the RGB Playback Switch.
- Select Video-In on the Abekas remote keypad.
- Proceed with recording.
- To view the result, deselect Video-In on the Abekas remote
keypad and select NTSC Encoder on the Editor Switch, then hit Play on the
Abekas remote keypad.
Record TBC'ed VHS (e.g., left VCR) to VHS (e.g., right VCR):
- Select 1/2" Left on the TBC/Scope Switch.
- Select TBC on the Editor Switch.
- Proceed with the recording.
- To view the result, select 1/2" Right on the Editor Switch.
Note: When the TBC is not receiving video (as in when it is connected
to a VHS VCR that is turned off), it will display nonsensical
output, usually fading to bright white. Do not be alarmed. As
soon as you give it a signal, it will behave normally.
Return to list of HowTo documents
Brian L. Curless / Stanford University / May 3, 1994
Major modifications: Fri Dec 22 1995 Tamara Munzner