Linn Basik Power Supply

[Sunsun22]

I need to build a Linn Basik Power Supply to experiment the connection of a Project Speed Box SE to a Linn LP 12 turntable. Can anyone provide me with the circuit and hints on how to build it?

Thank you

[Sunsun22]

Oops, forgot to mention my AC current is 220V 50Hz.

[tubenut]

Hi

From some very old notes.....
The Rega uses the same airpax motor as the Linn and the basic PSU used inside the Rega for 220 Volt operation is as follows according to my notes.

Live into a 0.22 MFD cap split in to two legs, one leg to Red windinfg and the other to another 0.22 MFD cap to blue winding.
Grey windings (2 of) are linked together and to neutral.
I played with these caps and found that the quality/type of cap has an audible / perceivable effect....


BTW, I later ran this motor from a Linn Axis PSU.....


Another supply cct is like a Armageddon

Search for Neil Turntable PSU page)

[Sunsun22]

The usual Linn Basik power supply has more component that two caps. What would be the difference?

Besides, I measured the voltage on the blue and red, they are 68V. Do I need a resistor to drop the voltage?

Thank you

[tubenut]

Not sure what you mean then by basic Linn supply has more then 2 caps. I checked with a buddy who used to work for the Linn importer and an independent shop as a technician. His old notes on the Linn psu are: Live direct to red, Live via 0.22 mfd to blue. Grey windings are joined and go to neutral trough another 0.22 MFD cap. Same as Rega iow but different sequence of series connection.

Perhaps Linn may later have added a resistor to further drop voltage and reduce motor vibration. Beware though as the caps and motor windings basically form a filter that reduces the voltage applied to the motor. Adding resistance will change this parameter as well.

[planet10]

Or they added a Valhalla like power supply/regenerator... essentially a sinewave generator + a poweramp to give really clean AC power.

I need to build one of these to adapt a 50 Hz Linn motor to our 60 Hz supply here.

dave

[Audiofanatic]

Tubenut:

BTW, I later ran this motor from a Linn Axis PSU.....

Hi Tubenut,

Do you have the schematic of this PSU (LINN AXIS)?
If so, can you please send me a copy?

TIA,


Audiofanatic

[tubenut]

Sadly I do not have a cct diagram for the Axis PSU. What I used was the real deal, salvaged, it was considered uneconomical to repair but my buddy managed to sort it.
I still have it and keep it as a spare for my Axis I use now.

It is quite complex. If you wish to copy one I could take some pics to give the general idea. If your unit is faulty, check the output devices, the high voltage caps and the 15K resistors. One of the 15K resistors went west on my Axis supply a week or so ago. According to my friend the outputs are the most common failure.

Linn dealers may be able to sell second hand valhalla units taken from decks upgraded to Lingo etc.....

Planet 10, dunno what it would cost but the Origin Live DC kit could also be an option. A friend fitted one to his LP12 and reckons it is fantastic. His was a valhalla deck. Feels it is the best upgrade he has done, better then cartridge changes and OL1 arm to silver arm.....

[Audiofanatic]

Hi Tubenut,

Thanks a lot.


Cheers,


Audiofanatic

[planet10]

Originally posted by tubenut
Planet 10, dunno what it would cost but the Origin Live DC kit could also be an option. A friend fitted one to his LP12 and reckons it is fantastic. His was a valhalla deck. Feels it is the best upgrade he has done, better then cartridge changes and OL1 arm to silver arm.....

Only wish i had that kind of budget....

dave