Luxman Line Phase Sensor

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I own a Luxman D-06 CD player. It has a line phase sensor which does not work. In the manual, it does not mention the sensor at all and I am thinking perhaps, Luxman decided to disable it. The power cable is a 2 prong as well with no ground. Although, some D-06 seems to have a 3 conductor power cable. Maybe the earlier models.

Does anyone know how the sensor is supposed to work? I've tried plugging the power in both ways and I assume the sensor is supposed to light up if the hot and neutral is reversed.

Great sounding CD player, by the way.
 
phase sensor is supposed to operate like a "testing" screwdriver .... I presume you have those in your country as well

to operate the phase sensor you need to touch the metal plate that is arround it and if the sensor glows then you are in the correct connection of your ac PLUG ( only part that looks metal since the rest is all black )

the idea is that if you have all you eq conected with the same flow of AC the conditions is better for power supplys to operate ..
 
phase sensor is supposed to operate like a "testing" screwdriver .... I presume you have those in your country as well

to operate the phase sensor you need to touch the metal plate that is arround it and if the sensor glows then you are in the correct connection of your ac PLUG ( only part that looks metal since the rest is all black )

the idea is that if you have all you eq conected with the same flow of AC the conditions is better for power supplys to operate ..

I do touch the gold metal of the sensor. The led light does not glow at all. I've tried reversing the plugs as it is only a 2 coductor plug. Nothing makes the light glow.

The info I've read is that it glows if the hot and neutral is reversed at the outlet. However, this only makes sense if the plug is a 3 conductor where you can only plug it in one way. Anyway, with AC, why does the hot/neutral really even matter from a operational standpoint. Maybe for safety concerns, yes, but sound? I listened to the unit plugged in both ways and can't tell any difference in sonics.
 
I found the reason why the phase sensor is not working. Someone have disabled it. A resistor has been removed (R501). Not sure why anyone would do this.

I am now trying to find the schematic for the D-06 but have difficulties. Can anyone assist or point me in the right direction to get a service manual for the D-06? I need to find out what the value of the resistor is so I can fix this problem...
 
the resistor is 2.2 M ( mega ohm ) 1/2W

( by the way the light is not comming from a led ... its coming from an inductive neon glow lamp no actuall filament inside )

Thanks for this info. I am just curious to why anyone would disable this. The dealer swears that they never opened the unit up. Would Luxman disable this feature for the U.S. models? Very strange.
 
More likely the part never got put in and that was never tested to see if it worked before shipping. It is a useful test.

I don't think so because the legs of the resistor is still there soldered in the pcb through hole. The resistor body was snipped out... Unless there is some sonic benefits of disabling this phase sensor circuit, I can't imagine why anyone would do this.

I suppose some also believe that by turning off the info screen of the deck, the music sounds better too. The D-06 has that feature where you can turn off the info screen lights.

I could not tell any sonic benefits by having the phase sensor circuit abled or disabled.. let alone, I heard no difference whichever way the plug was plugged in..
 
the resistor is 2.2 M ( mega ohm ) 1/2W

( by the way the light is not comming from a led ... its coming from an inductive neon glow lamp no actuall filament inside )


It occured to me, is this resistor value for the European model? That would be 220volts. The sensor circuit is connected directly to the neutral leg of the power input. So, here in the U.S. it is 120v AC. Considering current is volts / resistance, I wonder if the 2.2M ohm would be a correct value for the U.S. model?

With 220volts and a 2.2m resistor, it would be 1 microamp of current that is fed to the neon lamp. So perhaps, with the U.S. model, I need a 1.2M ohm resistor?
 
It occured to me, is this resistor value for the European model? That would be 220volts. The sensor circuit is connected directly to the neutral leg of the power input. So, here in the U.S. it is 120v AC. Considering current is volts / resistance, I wonder if the 2.2M ohm would be a correct value for the U.S. model?

With 220volts and a 2.2m resistor, it would be 1 microamp of current that is fed to the neon lamp. So perhaps, with the U.S. model, I need a 1.2M ohm resistor?

The resistor is just there for safety any value above 100K will work. The neon lamp will drop 60 volts or so. The remaining 60 at 100K would limit to .6ma, so even if you wet your finger and stood in a puddle you would at worst feel it but not be injured.

The idea is that the power transformer has the start of the primary windings closer to the core, so there is more coupling and noise if the start is connected to the hot lead.
 
Doing a bit of math, a 1/4 watt resistor would be more than enough, no?

I suppose the sensor could have been disabled for safety reasons? If the resistor shorted but that seems really unlikely. Resistor going open is much more common, I think.

Even with the resistor shorted there really wouldn't be any danger unless your feet were wet.

They probably used a fire resistant (Blue colored) resistor. The actual issue is not wattage but voltage rating! A 1/2 watt resistor is often rated for a maximum DC voltage above that of a 1/4 watt one. However for your use either will do!

If your other gear has a two prong plug you might try flipping it to see if you can hear a difference in the mid-range after you correctly plug in your repaired Luxman!
 
Even with the resistor shorted there really wouldn't be any danger unless your feet were wet.

They probably used a fire resistant (Blue colored) resistor. The actual issue is not wattage but voltage rating! A 1/2 watt resistor is often rated for a maximum DC voltage above that of a 1/4 watt one. However for your use either will do!

If your other gear has a two prong plug you might try flipping it to see if you can hear a difference in the mid-range after you correctly plug in your repaired Luxman!

I installed a 150k ohm 1w resistor as that is what I had on hand. The lamp works now.

Any guesses why anyone would make the effort to disable this sensor feature? I'm convinced it was done at Luxman as both the dealer and the seller claim they did not open the unit up. To get to this R501, there has to be some intent and technical knowledge.

I see no logical reason to disable it... weird..
 
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I installed a 150k ohm 1w resistor as that is what I had on hand. The lamp works now.

Any guesses why anyone would make the effort to disable this sensor feature? I'm convinced it was done at Luxman as both the dealer and the seller claim they did not open the unit up. To get to this R501, there has to be some intent and technical knowledge.

I see no logical reason to disable it... weird..

They were doing some evaluation experiment in the design department, asked for one unit, cut the resistor out bcs someone wanted to know if the sensor does something measurable or perceptible, it went back, the retrofit action was lost ''in the translation''. Just a scenario.
 
They were doing some evaluation experiment in the design department, asked for one unit, cut the resistor out bcs someone wanted to know if the sensor does something measurable or perceptible, it went back, the retrofit action was lost ''in the translation''. Just a scenario.

Quite possible. Not too impressed with Luxman distributor here in the U.S. No reply to my inquiries about this D-06. Not surprised with this lack of customer care that Luxman is not that well known in the U.S.

I for one wanted to check out a lower line Luxman to see if I liked the sound signature. If I did, I would have gone ahead and purchased the D-08.
 
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