Neolt NED 303 (plotter)

Published on 2022-04-10 and last edited on 2022-04-23.

⚓ Files

⚓ Description

PSU is an unregulated transformer, input fuse 250mA, output fuse 1.6A, around 19VDC unloaded

There is two steppers for the axis, pen lever is selenoid activated.

Each axis uses a UGN-3119U Hall-effect switch to detect homing.

Steppers are standard NEMA16 with a length of 33m, the shaft is 5mm then apx 3.3mm…

Fonts sets are builtin:

  • UNI 7559-B (ISO 3098/1)
  • DIN 17-262
  • DIN 1451

There is a memory of 1987 characters arranged in 10 pages, stored in a Dallas DS1225Y SRAM, unsocketted.

⚓ Belts

They will probably be cooked and not smoothy-circle, I am attempting to match new ones.

Everything in mm unless specified in cursed ".

⚓ Y axis

ModelLength (OD)Length (teeths*pitch)PitchTeethsWidthnotes
Original7773,1522.032 ?36~6.4
288MXL025 (Gates)73.082.032366.35imperial belt

⚓ X axis

ModelLength (OD)Length (teeths*pitch)PitchTeethsWidthnotes
Original9691,442.032 ?45~6.4
360MXL025 (Gates)91.442.032456.35imperial belt

There is also 4 open ones, two for each axis, width of 4mm, 2x21cm, 2x58cm, for a total of 158cm (1.58m).

They seems to match the profile of the two other axis so let’s assume they are MXL too, but in 4.76mm width.

Links of belts: