Johnmath:
The picture in #18 is the plug that connects the power supply of the turntable. The meter reads 5.28VDC as noted in #7.
Addressing the turntable's need as you stated in #19, then 0.528V could be "sufficient?" (FWIW, the only mention regarding the power supply I read on Amazon Audio's page was that the power supply delivered fifty times the current required for the motor. Current and voltage aren't the same, right?)
My intention is to see if a linear power supply can lower the noise floor and thus improve the sound. I intend to stick with the designer's idea of providing more current than necessary. Johnmath's ideas in #14 are beyond my ability and present available time to learn. I wanted to try an off the shelf design first, rather than have to troubleshoot my own design and soldering skills. So, thanks for sharing, even so.
I may be opening a can of worms here, but wanted feedback. The Hughes SMPS, if it's delivering 5V, is doing so with 1.65A, according to the case. Before starting this thread, I had measured 5.28VDC at the SMPS pin. I tried connecting an Uptone Audio UltraCap 1.2. Uptone states it delivers 5, 7, 9 and 12VDC. At 5V it only delivers 1.1A. The UltraCap did not spin my platter. I did not try 7, 9 or 12V on the table for concern that might wreak havoc. Is the apparent difference in amperage a reason the UltraCap did not operate in place of the Hughes SMPS?
Larry
The picture in #18 is the plug that connects the power supply of the turntable. The meter reads 5.28VDC as noted in #7.
Addressing the turntable's need as you stated in #19, then 0.528V could be "sufficient?" (FWIW, the only mention regarding the power supply I read on Amazon Audio's page was that the power supply delivered fifty times the current required for the motor. Current and voltage aren't the same, right?)
My intention is to see if a linear power supply can lower the noise floor and thus improve the sound. I intend to stick with the designer's idea of providing more current than necessary. Johnmath's ideas in #14 are beyond my ability and present available time to learn. I wanted to try an off the shelf design first, rather than have to troubleshoot my own design and soldering skills. So, thanks for sharing, even so.
I may be opening a can of worms here, but wanted feedback. The Hughes SMPS, if it's delivering 5V, is doing so with 1.65A, according to the case. Before starting this thread, I had measured 5.28VDC at the SMPS pin. I tried connecting an Uptone Audio UltraCap 1.2. Uptone states it delivers 5, 7, 9 and 12VDC. At 5V it only delivers 1.1A. The UltraCap did not spin my platter. I did not try 7, 9 or 12V on the table for concern that might wreak havoc. Is the apparent difference in amperage a reason the UltraCap did not operate in place of the Hughes SMPS?
Larry
The voltage for a good supply doesn't change with load (current draw). If the Amazon Audio statement that the turntable only 'needs' 1/10 of the power available, then that applies to the current available, not the voltage, so they are implying the motor uses 0.165A or 165mA. It is likely that the startup current exceeds that, however a decent 1A regulated supply should be more than adequate. It is the quality of the run-time voltage and current that will impact (if at all) on the quality of torque output from the motor.
If the UltraCap supply did not run the turntable it is most likely you connected it with the wrong polarity.
If the UltraCap supply did not run the turntable it is most likely you connected it with the wrong polarity.
johnmath:
Thanks for your time and knowledge.
Not sure how I could have done to change polarity. I'll see what I can learn about that.
Larry
Thanks for your time and knowledge.
Not sure how I could have done to change polarity. I'll see what I can learn about that.
Larry
A DC plug can be wired two ways; the center pin positive (+) and the shell negative (-), or the center pin (-) and the shell (+).
There is no 'correct' or 'standard' wiring, although I think (+) pin is more common. You can determine the polarity if you have a multimeter an check to see if the Amazon Audio (Hughes) power supply is wired the same way as the UltraCap one. If the UltraCap supply has different polarity, then it won't run the turntable and may damage it.
There is no 'correct' or 'standard' wiring, although I think (+) pin is more common. You can determine the polarity if you have a multimeter an check to see if the Amazon Audio (Hughes) power supply is wired the same way as the UltraCap one. If the UltraCap supply has different polarity, then it won't run the turntable and may damage it.
An SMPS supply can be either current limited or shut off when the current limit is exceeded.
A motor draws a higher current on start up as it is not spinning and creating a back emf.
The instantaneous current is only limited by the DC resistance of the motor.
A current limited supply will start a motor and limit the maximum current that can be drawn.
A supply that cuts off when the current is exceeded will not start a motor that exceeds the trip current.
However, in this case, the current will likely be set by the motor controller circuit.
The motor control circuit will influence how the motor behaves. The SMPS supply not at all.
So I really don't understand why you are doing this.
Your level of expertise says you shouldn't as you may very well damage a very nice turntable:
If you had more experience then you'd know enough to realise this is a fool's errand.
A motor draws a higher current on start up as it is not spinning and creating a back emf.
The instantaneous current is only limited by the DC resistance of the motor.
A current limited supply will start a motor and limit the maximum current that can be drawn.
A supply that cuts off when the current is exceeded will not start a motor that exceeds the trip current.
However, in this case, the current will likely be set by the motor controller circuit.
The motor control circuit will influence how the motor behaves. The SMPS supply not at all.
So I really don't understand why you are doing this.
Your level of expertise says you shouldn't as you may very well damage a very nice turntable:
If you had more experience then you'd know enough to realise this is a fool's errand.
Russc:
I know that I don't know much about this topic. Hence an inquiry to people who theoretically and very likely know more than I.
As I stated previously, "why" is to see if I can reduce noise to a meaningful extent. How and whether to do it is implicit in my reasons for asking for advice here.
FWIW, surprisingly the table designer is accepting my emails several years after his retirement. I told him my intention and I'll follow his guidance. I do appreciate your warning, however.
Larry,
the cautious fool
I know that I don't know much about this topic. Hence an inquiry to people who theoretically and very likely know more than I.
As I stated previously, "why" is to see if I can reduce noise to a meaningful extent. How and whether to do it is implicit in my reasons for asking for advice here.
FWIW, surprisingly the table designer is accepting my emails several years after his retirement. I told him my intention and I'll follow his guidance. I do appreciate your warning, however.
Larry,
the cautious fool
After seeing this:
Amazon Audio Components Model 2 turntable
Manufactured by Amazon Audio Components
Price CDN$5500.00 -- price includes Moerch UP-4 arm (cartridge extra)
I have to wonder why anyone would chance any attempt at trying to "better" this record playing machine.
A quick check of glowing reviews certainly give it high ratings.
Amazon Audio Components Model 2 turntable
Manufactured by Amazon Audio Components
Price CDN$5500.00 -- price includes Moerch UP-4 arm (cartridge extra)
I have to wonder why anyone would chance any attempt at trying to "better" this record playing machine.
A quick check of glowing reviews certainly give it high ratings.
All people have blind spots, even designers of expensive turntables. In 50 years I don't think I have encountered a turntable that I couldn't improve with simple attention to detail, although the most expensive turntables I've serviced have all been under US$30,000 new, which excludes some of the more expensive decks.
+1 to wiseoldtech.
Advice to any newbies: Don't take everything you read on the forums as gospel.
DIYAudio has it's share of snake oil purveyors and such.
Advice to any newbies: Don't take everything you read on the forums as gospel.
DIYAudio has it's share of snake oil purveyors and such.
Unfortunately that cuts both ways. A lot of 'anti-snake oil' advise emphatically dished out by know everything participants on DIYAudio is false and unhelpful too, and I am not talking about anything that contravenes the laws of physics as known and understood, nor especially accusing anyone in this thread, just making a comment.
My dad was an engineer. There is a funny blind spot with engineers, expressed (with a friendly smile) in the following joke:
"Engineer's sex manual: Insert male body part. Move in and out. Repeat as necessary."
Necessity addresses the ground floor but not the aspirational heights of the undertaking. To be direct, necessity is not the point of my interest. Pleasure is.
If something goes amiss with my experiment, no one will die and no one else on this forum will have lost money. I hope my friendly joke is appreciated and no one takes offense.
Larry
"Engineer's sex manual: Insert male body part. Move in and out. Repeat as necessary."
Necessity addresses the ground floor but not the aspirational heights of the undertaking. To be direct, necessity is not the point of my interest. Pleasure is.
If something goes amiss with my experiment, no one will die and no one else on this forum will have lost money. I hope my friendly joke is appreciated and no one takes offense.
Larry