Parts

External Clock for jitter reduction

Job 2

Hook up the low jitter clock from the XO3 pcb to the PRO2LF pcb.

The wire pair to hook up is the purple / black pair. In the picture to the right the capacitors are however not yet removed. They should be removed before hooking up the pair.

The purple wire should be connected to the x-tal island between pen 3 and 2 of the former x-tal. This is the same as pin 16 of the IC. It is recommended not to solder direct on to the IC.

The black wire of the purple / black pair should be connected to the former ground connection of the capacitor. See the exact arrow top for this. It is not a big solder island but close to the ground hole

Leave the wires twisted. For additional instructions see the pdf download file with support from TenTlabs

IMPORTANT: As the servo decoder chip runs on 3.3V a resistor of 100 Ohm needs to be mounted parallel between the purple and black wire close to or on the PRO2LF PCB. The tolerance of the resistor is not critical.

100 Ohm resistor

Job 3

Hook up the power supply to the XO3 PCB. General solution

The ground part of the power supply was connected in Job 2. Do not use a second or separate ground. The V+ being the single red wire is the only one to connect. As the current is only modest there is no requirement to use a thicker wire. It is allowed to increase the length.

The input V+ voltage needs to come direct from the power supply used for the CD-PRO2.

Best is to use the voltage from the input of the regulator for the +9V. It is not possible to give more detailed instructions as you need to design the power supply your self. The output voltage of the regulator is more smooth but is not high enough as you need in excess of +10V. See also job 7 for the specific solution

The by now reached status allows to test implementation of the low jitter external system oscillator. The internal DAC will be driven by the low jitter clock as well as the rest of the decoding system. Any DAC unit connected to the Spdiff will work as well but will not be re-clocked. Enjoy listening for a moment to the achieved result and then get back to work.

Job 4

Test the implementation of the low jitter external system oscillator

Job 5 and 6

Hook up the Spdiff re-clock circuit.

Connect the yellow/black pair to the indicated points.

Yellow goes to a soldering pad and black to the ground side of the capacitor. The Spdiff signal is now tapped.

At the white/black pair the re-clocked signal is now available. For test purposes the new signal can be compared with the original signal as both are available. For best results the resistor as indicated by the green arrow needs to be removed. After removal only the XO3 board will be connected to the Spdiff pin of the decoder IC. It will no longer be possible to compare after the removal of the resistor.

This completes the instructions. For job 7 see here…..

By now the XO3 board is fully operational.

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