Accessories
Battery Pack
The included battery pack takes 6 1.5v D-cell batteries, in series, for a total of 9v. It is swappable for the PP-1 AC power adaptor.
I believe this came with the keyboard, though none of the three I bought came with one, so I ordered one off eBay.
Music Rest
The metal wire music rest attaches on the top of the keyboard, and can be stowed on the bottom panel for storage.
Again, none of my 3 keyboards came with one 😠I’m actively looking for one
Dust Cover
A vinyl dust cover was included in the box. It says “YAMAHA” in the bottom right corner.
PP-1: AC Power Adaptor
This 15W AC power adapter replaces the battery pack on the back of the keyboard, providing 600mA of 9v DC power.
It seems there are multiple versions of this power adaptor. One version only supports 120v 60Hz AC power, while the other supports 220-240v and 50hz AC input. The latter also has a switch to select which mode to use.
I’ll likely create a schematic for this power supply, but for now, here’s some component details:
- Two TKK transformers. 240v model has different transformers with an additional tap selected by a switch.
- Two rectifier diodes (1D2Z1+1D2C1 or S2VC)
- The capacitors are:
- one line-to-earth EMI suppression cap (PME265 or 2B473M)
- two 25v 1000µF electrolytic
- one 16v 10µF electrolytic
- one 100nF ceramic disc
- There’s an internal 5kΩ trimmer, maybe for voltage adjustment
- It uses a 7808 voltage regulator
- 4 390Ω resistors