The Commodore NEO Rev 3 & 4 PCB Build Experience

I wanted to document my experience with doing the Commodore 128 NEO PCB build, which my daughter and I performed on a REV3.3 and REV4 board. This was a fun project, and granted, there are some minor bumps in getting it all said and done, but it was both a valuable and prideful experience. Mental note, order as much as you can from Mouser and Digikey with one order each - it will save you a lot of shipping costs in the long run!

  1. the PCBs - Rev 4 is the latest out there, found on the GriffinRetro store at Tindie and Ebay amongst other stores. Rev 4 is great in that it captures all the lessons learned and includes a custom made video section to replace the RF modulator as well as EMI Joystick port protection.

REV3 NEO PCB for Commodore 128

The support area is awesome, featuring a very helpful Build Material List (BOM) as well as an interactive component placement guide to help with the installation.

Some of the parts listed in the BOM were obsolete and no longer manufactured. We were able to get around this in a few ways. One way was we had in stock several older C128 boards. Notable items were:

  • 0.1uF Capacitors (51 of them needed!). These were ordered from several manufacturers, all on backorder to the day of this blog. That said, there were some Commodore stores like that carry a pack of 10 (and limits 1 order at a time). I will update this section once we get our backorder from Mouser electronics.
  • Electrolytic 1-uF 50V capacitor PN USA1H010MDD1TE (C91) no longer manufactured. We replaced this with a similar-properties capacitor part number 2322-50PX1MEFC5X11 and will advise once tested. Alternative is to buy a capacitor pack from a reputable Commodore store.
  • The full bridge rectifier P/N 251026-01for the REV 4 was hard to find - and we finally located it at VETCO. For the REV 3.3 board, this P/N will not fit and we ended up salvaging an existing one off our C128 spares.
  • Rocker switches (DP/DT) for power were on Retroleum and E-bay
  • The 16 MHz Oscillator (Component Y1) P/N MX045-2C-16M0000 was listed as obsolete and replaced by 3C version. Will advise once we test!
  • 8701 Clock Generator (U28) ordered from
  • Murata Ferrite Bead components (FB-XX on the board, P/N BL02RN2R1M2B) were near-impossible to find unless you were willing to pay hundreds of dollars per component. The BOM notes that these parts are not available and “No Replacement has been found”. Well, we finally DID find these at Aliexpress. We will advise how testing goes with these components in place.
  • EMI component(s) P/N EMI470T-RC was difficult to locate. Both Mouser and Digikey were a no-go/discontinued. We finally found them at where you have to order 80 minimum (where only 5 are needed), but they were there! We are selling our extras here.

We’re excited to light these boards off once complete and will update this blog accordingly!!

My REV4 board:

Daughter’s REV 3 board: