When adjusting focus balance, looking at the diamond pattern, I've read many places here, that it should be both large and clear.
So, is that done on the same trimmer?
And is focus balance the same is E-F balance? If not, how does one adjust E-F balance on a teac vrds-10?
Kind regards,
Jacques
So, is that done on the same trimmer?
And is focus balance the same is E-F balance? If not, how does one adjust E-F balance on a teac vrds-10?
Kind regards,
Jacques
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E-F balance is sometimes called Tracking Balance and relates to ensuring the beam falls equally on all the photo diodes in the array. E and F refer to the 'outer' pair of photo diodes in the group of six. A,B,Cand D are the group of four in the centre.
See if this gives you any clues (post #1):
Sony CDP790 and KSS240 Restoration Project
See if this gives you any clues (post #1):
Sony CDP790 and KSS240 Restoration Project
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Thanks Mooly.
Now I know that it's the same as Tracking Balance.
I've been watching the eyepattern, and if making even a slight adjustment on Tracking Balance, it is shown in the eyepattern too.
I went for the biggest and clearest eyepattern I could get.
I just have a hard time trying to make the scopes readout for Tracking Balance look like the signal shown in the service manual.
Kind regards.
Now I know that it's the same as Tracking Balance.
I've been watching the eyepattern, and if making even a slight adjustment on Tracking Balance, it is shown in the eyepattern too.
I went for the biggest and clearest eyepattern I could get.
I just have a hard time trying to make the scopes readout for Tracking Balance look like the signal shown in the service manual.
Kind regards.
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You can only adjust tracking balance under specific conditions which normally involve putting the unit into a service mode that unlocks the tracking servo.
Just try the easy method of looking at the tracking error waveform during track jumps. It is totally accurate doing it that way. You will not see any real change in the eye pattern, the adjustment is a servo tracking one. Slow the scope timebase right down and keep flicking through large track jumps such as track 1 to the last track on the disc and back again. During the time it is jumping is when you adjust the preset.
Focus bias is the adjustment that will optimise the eye pattern.
Just try the easy method of looking at the tracking error waveform during track jumps. It is totally accurate doing it that way. You will not see any real change in the eye pattern, the adjustment is a servo tracking one. Slow the scope timebase right down and keep flicking through large track jumps such as track 1 to the last track on the disc and back again. During the time it is jumping is when you adjust the preset.
Focus bias is the adjustment that will optimise the eye pattern.
For pick-ups which uses a conventional worm drive to move the laser head I find that the method of flicking between the first and last track on a discs works very well for checking the E/F balance.
You do this whilst observing the tracking error waveform (usually marked TE on Sony based players) and not at the RF eye pattern test point.
However, the KSS-151A will change tracks so lightening fast I find that method doesn't work. Instead, what I do is to PAUSE a track and then slow the scope right down until you can see a 'pulse' pan slowly across the scope screen. Adjust until the pulse is centred around the 0v line.
For focus bias adjust for highest peak-peak amplitude of the RF eye pattern, which is usually the same as 'best' clearest eye pattern.
You do this whilst observing the tracking error waveform (usually marked TE on Sony based players) and not at the RF eye pattern test point.
However, the KSS-151A will change tracks so lightening fast I find that method doesn't work. Instead, what I do is to PAUSE a track and then slow the scope right down until you can see a 'pulse' pan slowly across the scope screen. Adjust until the pulse is centred around the 0v line.
For focus bias adjust for highest peak-peak amplitude of the RF eye pattern, which is usually the same as 'best' clearest eye pattern.
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