Luxman D-111 alignment

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newbie Geezer with ancient audio system, I can't bear the thought of buying something I'll barely use in the last 1-30 years of my life... Misdirected EE who ended up as a computer geek and therefore has limited useful knowledge :). I think I can steal a 'scope somewhere for this; I do have a good fluke dmm but that's probably not much use. I thought this should be a fairly generic common procedure but I've had trouble finding much info. Can anyone tell me the proper alignment procedure for a Luxman D-111 CD player? I see the following pots: 1. TE Balance (Tracking Error?) 2. F Gain 3. T Gain 4. Focus Bias 5. VCO I'm assuming F means "Focus", T means "Tracking". TE means "Tracking Error"? VCO means ??? It's not clear to me where the appropriate test points are. There are small white circles with labels around one of the mounting holes for some components: 1. TE 2. FE 3. RF 4. ADJ (2) 5. VCO Are these actually test points? I'm guessing TE and FE are for scoping tracking and focus error? Any idea what the two ADJ points are? The VCO label is also near the pot labelled VCO. If anyone can tell me the actual alignment procedure, that would be great. If you've got a service manual that describes it I'd be ecstatic. Any comments about the usefulness of the service manual? The only thing I've been able to find was this: repair cd-player repairing cd-player cd-player help adjust cd-player repairing manual Thanks, Gary
 
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VCO means "Very Critical oscillator", in other words do not touch without reference to the manual :)

In fact without a manual or experience you shouldn't just twiddle any adjustments... however.....

VCO (voltage controlled oscillator) needs a frequency counter and the manual. It never ever normally needs adjusting.

An experienced technician could "busk" a set up procedure something along the lines of...

1. Tracking and Focus gain to mid points. These can be surprisingly uncritical and help determine how well the pickup tracks damaged discs or when the pickup is subject to mechanical shock.

2. Play a good CD and with scope on the RF test point adjust focus bias for the clearest "eye pattern" by looking at the "diamond" part of the waveform. You have to use the correct ground for the scope too as not doing so can in some case add noise to the result making it look worse than it is.

3. Confirm the amplitude is good (this is directly related to laser power). If amplitude is low the pickup could be bad/dirty etc. Again a manual for the correct value but 1.2 to 1.5 volts peak to peak are typical values.

4. TE/EF balance... follow a manual to be sure or, scope AC coupled on TE (tracking error) test point and set to a slow timebase speed. Using the track jump keys adjust so that the waveform appears symetrical above and below an imaginary centre line. Should be symetrical during playback too.

6. Focus gain... turn up slowly until the pickup sounds noisy (white noise... and this is somewhat pickup dependant so just a generalisation). Back off slightly from that point.

7. Tracking gain... scope on TE point and slow timebase speed. Turn gain up until a very low frequency fundamental appears in the waveform. Back off slightly from this point so the fundamantal just disappears.

Edit... the two "adj" points could be for setting the VCO and you would need the manual to know the procedure.

A "good" CD player with a good pickup and mechanics is very tolerant of misalignment. If it all appears super critical to get it to play all discs all the time etc then there is some other problem other than alignment.
 
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