TurntablePSU.comReviews and Technical Analysis
Linn Axis Motor Controller
Overview
The Linn Axis Motor Controller is a dual frequency, dual phase analog oscillator that is used only with Linn turntables. It has one button to switch between 33/45 RPM and to switch between standby and run.
Circuit Description
The Linn Axis controller uses an analog oscillator consiting of U3 configured as a dual integrator state variable filter with quadrature output (O1 and O2). The two outputs are amplified by U4 and Q5/Q8 which form 2 high voltage amplifiers. The outputs are AC coupled to the motor windings. R35 and R37 provide analog adjustment of the frequency; the phase and amplitude are fixed. The Axis can be powered by 115/230VAC but the output is 115VAC only.
Specifications
Nominal Speeds...........................33 and 45 RPM .
Speed Stability.............................Not defined
Distortion (Freq Generator)............Not Available
Distortion (115VAC output)............Not Available
Pitch Control................................Not adjustable
Output Power...............................3W
Reduced Voltage..........................Not available
Motor Connection.........................120VAC
Linn Lingo Motor Controller
Overview
The $1550 Linn Lingo Motor Controller is a dual fixed frequency, dual phase crystal contolled oscillator that is used only with Linn turntables. It has one front panel button to switch between 33/45 RPM (long press) and between standby and run (short press). There is a power switch on the back turn the unit on/off. The Lingo is designed to work with 230VAC inputs and 50Hz 115VAC motors on the output.
Circuit Description
The Linn Lingo controller uses two crystal oscillators (3.2768/4.42268 MHz) to generate the frequency for 33 and 45 RPM. The selected crystal frequency is divided by 65,536 to create 50Hz or 67.5Hz (33/45 RPM). U1B/D and U2B/C form a 8 Pole LPF/HPF with cutoff frequencies of 20Hz and 90Hz. There are separate level controls for 33 and 45 RPM, but the output level is fixed during operation. U2A delays the output of the filter by 90° and U3 selects different time constants for 33/45 RPM to maintain 90° over both speeds. The output of the LPF and the phase delay drive U1A/C which drive the HV output amps. The output of the HV amps are capacitively coupled to the windings of the motor. The Axis is powered by 230VAC but the output is 115VAC only.
Specifications
Nominal Speeds............................33 and 45 RPM .
Speed Stability..............................0.01% (100 PPM)
Distortion (Freq Generator).............Not Available
Distortion (115VAC output).............Not Available
Pitch Control.................................Not adjustable
Output Power................................3W
Reduced Voltage...........................Not available
Motor Connection..........................115VAC
Dimensions...................................12.5"W x 12.5"D x 3.1"H
Weight..........................................3.3 lbs.
Retail............................................$1550
Linn Valhalla Motor Controller
Overview
The Linn Valhalla Motor Controller is a single frequency, crystal oscillator controller that is used only with the Linn turntables.
Circuit Description
The Linn Valhalla controller uses single quartz crystal oscillator at 3.2768 MHz (50Hz) or 3.93216 MHz (60 Hz). The crystal frequency is divided by 65,536 by U3 (MC4060) and U5 (MC4013) to produce 50 or 60Hz. RV1 control the output level and U2A/D forms a 4 pole low pass filter. U2C, Q1-4, Q11 and Q22 form a high voltage amplifier which is AC coupled to the motor. The Valhalla can be powered by 115/230VAC but the output voltage is 115VAC only.
Specifications
Nominal Speeds...........................33 RPM .
Speed Stability.............................0.01% (100 PPM)
Distortion (Freq Generator)............Not Available
Distortion (115VAC output)............Not Available
Pitch Control................................Not adjustable
Output Power...............................3W
Reduced Voltage..........................Not available
Motor Connection.........................115VAC