Skiratcha Tonearm Install Guide
-adds an m44-7 compliant tonearm with integrated phono preamp to the Numark PT01USB, and PT01-Scratch
Parts needed:
-Skiratcha Tonearm kit
-Philips Screw driver
notes:
-the Skiratcha Tonearm has an integrated RIAA phono preamp. Do not install an additional preamp.
-the spring counterweight adds the ideal weight for record playback. Add the optional black tension band (see step 41) to increase stylus weight, while scratching
-touch the Skiratcha chicken head to turn on/off the headshell lights
-use the integrated bass kill slide switch to turn on/off bass kill
-add platter bars for best bounce performance
-Before You Start: Test Your PT01
-Any defects in performance will likely still be present after upgrading the tonearm. Fix them first
-Make sure the power turns on and you see the red power light (next to the 33/45/78 rpm switch)
-Listen to a record using headphones connected directly to the PT01’s headphone jack
-Using headphones, make sure the left and right audio channels are both working
-Using headphones, listen closely for any audio hum or buzzing
-Using headphones, turn on the motor without playing a record
-Listen for any pops or hum, while the motor is turned on and off and while the motor is running
-Remove Existing Tonearm (part 1)
1. See tonearm removal guide. Keep the tonearm axle for the Skiratcha install.
-Open the PT01
2. Remove the 8 screws on the bottom of the PT01 (see pic_1_open_pt01)
3. On the PT01’s USB board, unplug the red and white audio connectors (see pic_2_USB_cables)
4. On the PT01’s power supply board, unplug the TE14 red/white power cable and the TE12 black ribbon cable (see pic_3_power_cables)
-Remove Existing Tonearm (part 2)
5. On the PT01’s main board, remove capacitors C8 and C18. The easiest way to do this is to clip the leads with wire cutters or fingernail clippers. Cut the capacitor legs flush with the main board, so they do not touch each other or other parts of the main board (see pic_4_remove_capacitors_and_wires)
6. On the PT01’s main board, remove the existing tonearm wires. Cut the existing tonearm wires from the “R IN”, “GND”, and “L IN” bars. Cut them as close to the bars as possible, so they do not touch each other (see pic_4_remove_capacitors_and_wires)
-Mount the Tonearm Clip
7. On the platter side of the PT01, mount the tonearm clip. Remove the paper backing from the clip’s adhesive, and press it onto the existing tonearm clip. Note the orientation of the clip’s step groove (see pic_5_clip_install)
-Mount the M44-7 Cartridge
8. Remove the stylus from the m44-7 cartridge. This will avoid damage to the needle during the tonearm install.
9. Connect the m44-7 to the tonearm wires (see pic_6_headshell_wires)
10. Mount the m44-7 onto the headshell using the included black screws, nuts, and hex key. The screw head should be on the top side of the tonearm, and the nut should be below the cartridge (see pic_7_mount_m447)
-Mount the Tonearm
11. Feed the Skiratcha tonearm wire through the spring clip using the included tweezers. Note that the flat part of the spring clip should face upwards towards the tonearm (see pic_8_spring_clip)
12. Feed the Skiratcha tonearm wire through the PT01’s tonearm base (see pic_9_base_wire)
13. Press fit the spring clip into the PT01’s tonearm base. Make sure to press the spring clip all the way down (see pic_10_spring_clip_installed)
14. Align the holes in the Skiratcha tonearm’s base with the PT01’s metal tonearm base. Remove the slack in the tonearm wire by gently tugging on the tonearm wire from inside the PT01.
15. Press the smooth end (not the knurled end) of the tonearm axle through the tonearm base, PT01 metal base, and spring clip (see pic_11_tonearm_axle)
16. Look through the hole on the opposite side of the tonearm to align the tonearm holes with the holes in the PT01 base, and press the knurled side of the tonearm axle into the tonearm (see pic_12_hole_alignment)
17. Press fit the neck of the Skiratcha tonearm into the tonearm clip to secure the tonearm (see pic_13_secure_tonearm)
-Connect Tonearm Wires to Tonearm Adapter Board (TAV2)
18. Close and lock the PT01’s lid onto the top half of the PT01. This will protect the tonearm, while we complete the install (see pic_14_close_lid)
19. Pick up the top half of the PT01 and place it on a table with the cover side down
20. Bend the Skiratcha tonearm wires into a pitchfork shape. The wire order should be black (GND), white (right), yellow (left), red (+). Make sure that the exposed wire ends are bent back onto the wires insulation. The adds strength to the wire, when connected to the green terminal block (see pic_15_wire_ends)
21. On the Tonearm Adapter board, use the supplied blue screw driver to loosen all 4 of the green terminal block screws (i.e., open all 4 terminal block holes)
22. Insert all 4 Skiratcha tonearm wires into the Tonearm Adapter board’s green terminal block at the same time. Make sure the wires are inserted all the way into the terminal block (see pic_16_terminal_block)
–Very important: note the wire orientation: black (GND), white (right), yellow (left), red (+)
23. Tighten all 4 terminal block screws
-Connect Tonearm Adapter Board (TAV2)
24. On the PT01 main board, unplug TE13 (see pic_17_TE13)
25. Connect the TE13 wire from step 24 to the “USB” header on the Tonearm Adapter board (see pic_18_USB_header)
26. The Skiratcha tonearm kit includes a white 3-pin cable with plastic plugs on each end. Connect one end of this cable to the “MAIN” header on the Tonearm Adapter board (see pic_19_main)
27. Plug the other side of the cable from step 26 into header TE13 of the PT01’s main board (see pic_20_main_TE13)
28. On the PT01 power supply board, unplug the connector from header TE14. This should have been done in step 4 (see pic_21_TE14)
29. On the PT01 power supply board, remove the screw closest to TE14 (see pic_21_TE14)
30. On the PT01 power supply board, install the Tonearm Adapter board. Insert the PT01’s mounting screw, and make sure it’s tight (see pic_22_mount_TAV2)
31. Insert the red/black 2-wire plug from the Tonearm Adapter board into TE14 (see pic_23_TAV2_TE14)
–Very important: note the wire orientation: black (VCC), red (GND)
32. Plug the cable from step 28 into the “PT01” header of the Tonearm Adapter board (see pic_24_PT01_TE14)
-Reconnect PT01 Wires
33. On the PT01’s power supply board, reconnect the PT01’s black ribbon cable to header TE12 (see pic_25_TE12)
34. On the PT01’s USB board, reconnect the red and white audio cables (see pic_26_USB_cables2)
35. Align and place the top half of the PT01 onto the bottom half of the PT01 (don’t put the 8 screws into the bottom side, yet)
-Skiratcha Tonearm Spring Counterweight
36. Open the lid of the PT01
37. Stage the PT01 to get a good view of the back of the Skiratcha tonearm
38. On the back of the Skiratcha tonearm, grip the ring of the counterweight spring with the supplied black tweezers
39. Angle the tweezers at a 45 degree angle (with the the tip of the tweezers pointing upwards), and pull the spring towards the tonearm’s spring anchor (see pic_27_spring)
40. While keeping the tweezers’ angle at 45 degrees, place the ring of the counterweight spring onto the spring anchor (see pic_28_anchor)
-Optional: Scratch Tension Band
Note: The tension band adds stylus weight above the recommended Shure M44-7 tracking weight of 5 grams. Only add the tension band for scratching.
41. Place the black tension band over the Skiratcha tonearm neck (see pic_29_neck_tension)
42. Attach the tension band between the Skiratcha tonearm neck and the PT01’s tonearm base (see pic_30_tension_base)
-Test
43. Reinstall the M44-7 stylus (see pic_31_stylus)
44. Turn on the PT01’s power and look for the PT01’s red power light (next to the 33/45/78 rpm switch). If the light doesn’t turn on, immediately turn off the power. Check the red/black cables on all of the connectors, and try again.
45. Test the audio output of the PT01 using stereo headphones. Make sure the left and right audio channels are present (see pic_32_headphones). If there are any stereo audio issues, check the wires in step 22.
-Reassemble
45. Close and lock the PT01 lid
46. Flip the PT01 over, and install the 8 case screws into the bottom. Make sure that none of the ribbon cables or wires are stuck between the screw mounts or PT01 edge, before tightening the screws (see pic_33_reassemble)
