Hi Guys

As per the title, I'm after a used Valhalla circuit board in any condition but preferably with the on/off switch.

Cheers

Graham

new project graham ?

YEP !!!

I'm toying with the idea of powering the AC synchronous motor in my Oracle Delphi with a Valhalla instead of the Geddon Clone currently in use.
I would of course modify it as I have done previously to provide two speeds, 33 and 45.
It is so simple to do you have to wonder why on earth Linn didn't do this instead of the silly add on pulley adaptor.

Cheers

Hi Graham - how do you see the Valhalla as being different from the Geddon?
Synthesising a perfect AC sine wave?

You may be familiar with Altmann's DIY TT?
The motor control in particular - www.altmann.haan.de/turntable/

Keep up the good work

DarkLantern blog - darklanternforowen.wordpress.com

Hi Owen

 1) Possibly a better sine wave for even smoother motor operation.

2) 2 speeds when modified.

3) Just for fun and to experiment .

what about 78s

Mar 14, 2018 9:42:35 GMT 12 michaelw said:

what about 78s

And 16

I am a non-recovering audioholic, and Ivor is my higher power.

A synchronous motors rpm is controlled by the frequency being fed to it. Not voltage.
The Valhalla has a crystal that determines the frequency of its ac output voltage.
Within reason any rpm could be achieved simply by using the appropriate crystal.
My modification simply involves having two crystals on a separate little circuit board with appropriate resistors, and a double throw switch to select either to provide the frequency for 33 or 45 rpm.
This is actually all that is inside a Mose Hercules PSU.
Cheers