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trying to understand the Linn motor

I have an old Valhalla Linn and it may be time to change its motor.
The board has been serviced and all caps upgraded.
As far as I can tell, the board produces 85 volts at 50 Hz.
If I am wrong on this, please let me know.

However, the motor on the Linn (Premotec 9904 111 31813) is 
rated at 110 volts (with -15% +10% voltage tolerance according to its spec).
This indicates that the motor should not be driven with less than
93.5 volts (-15%).

So, what am I missing ?

Thanks


128x128cakyol
cakyol's avatar
cakyol OP
940 posts
 
My situation is a bit weird....

I have an Ariston RD11 in the US.  Its Valhalla board has the 3.9Mhz crystal (for 60Hz).  However, at the output, it has the 0.22uF capacitor designed for the "110 V ac-50Hz: C=0.22mF, speed = 250 rpm" output.

I cannot figure out what the board is outputting.  Is it 50Hz or 60Hz ?

I need a scope to figure it out.


cakyol's avatar
cakyol OP
940 posts
 
I need a 50Hz pulley for my US Ariston since moving to a hercules board requires the motor to be driven at 50 Hz.  I can always change the 45 rpm crystal on the hercules to a 3.9Mhz and make it work at 60 Hz but that is my last option.  This way, I could drive both 50Hz or 60Hz motors, but I prefer the pulley method first.
Thanks

btwsg
9 posts
 
Linn likes to run the TT motor at lower voltages to reduce motor vibrations... The Lingo drops the voltage to 60V once it stabilise... The Valhalla is locked at 85V all the time.
cakyol's avatar
cakyol OP
940 posts
 
I almost always give my platter a hand spin as I power it on to make it easier on the motor & the belt.  I guess as long as I continue doing that I can probably lower the voltage even more (like 60V as in Lingo).

I wonder what the lowest threshold voltage is for it to stop altogether.  I will make that experiment one day....


teo_audio
2,197 posts
 
My memory is faulty on that re the two step voltage thing... as I lowered the voltage of the sine on my rebuilt Valhalla board and now sometimes assist the platter when it is spinning up.

Never bothered with the lingo yet, as....I'm waiting for the right auction/sales snipe moment.

Cheap ass, like many analog guys. So cheap (and dedicated) I got into the audio business, to get closer to the source point.
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