22-08-2025, 06:32 AM
(This post was last modified: 22-08-2025, 06:41 AM by ppppenguin.)
Which model Vectorscope do you have? Incidentally, Vectorscope is strictly speaking a Tektronix trademark but has become generic. It's of little use outside a TV studio or other facility where pictures are being originated. now that PAL and NTSC are obsolete it has much less meaning in a component environment, whether analogue or digital.
Your Grundig generator is giving a fairly nasty waveform. Lots of overshoots and no breezeway. That the gap between the end of sync and start of burst. Some TV mender's generators are much worse!
Perhaps surprisingly the vector display is pretty good. The dots are fairly clean and more or less in the boxes. The lines joining the dots are faint as expected but pretty straight. They can be quite curved or loopy. Though it's easy to blame the generator for errors in the vectorscope. When you're setting up a PAL or NTSC coder the vector display is only a final check. Most of the adjustments are done with a waveform monitor or oscilloscope.
Some vectorscopes have extra functions. My Tek 1755A, the last generation of classic analogue instruments, can measure SCH phase (the phase relationship between subcarrier and H sync) which is difficult to do. It's critical for editing on broadcast grade analogue analogue VTRs. It's also difficult to measure without a specialist instrument. It can also strobe out individual lines from anywhere in the 8 field PAL sequence.
Your Grundig generator is giving a fairly nasty waveform. Lots of overshoots and no breezeway. That the gap between the end of sync and start of burst. Some TV mender's generators are much worse!
Perhaps surprisingly the vector display is pretty good. The dots are fairly clean and more or less in the boxes. The lines joining the dots are faint as expected but pretty straight. They can be quite curved or loopy. Though it's easy to blame the generator for errors in the vectorscope. When you're setting up a PAL or NTSC coder the vector display is only a final check. Most of the adjustments are done with a waveform monitor or oscilloscope.
Some vectorscopes have extra functions. My Tek 1755A, the last generation of classic analogue instruments, can measure SCH phase (the phase relationship between subcarrier and H sync) which is difficult to do. It's critical for editing on broadcast grade analogue analogue VTRs. It's also difficult to measure without a specialist instrument. It can also strobe out individual lines from anywhere in the 8 field PAL sequence.
www.borinsky.co.uk Jeffrey Borinsky www.becg.tv
