Korg Poly-61 Boards

The two Poly-61 versions

The Poly-61 exists in at least two versions, an old production and a new production version. The following image shows the old production version, in the newer models, you won't find the boards numbered 5 and 6. Both models are described below and are not easy to distinguish without opening them, even that i have seen a difference in the models which i have seen for now, which is the color of the power cable.

The old production model

The following boards are found in the old production model. My two old models have a gray power cable.

1	Clock-board	contains the master oscillator and handles the joystick functionality.
2	Programmer-board	the main user interface to select and edit programs.
3	Assigner-board	controlling voice assignment and the arpeggiator.
4	Connector-board	contains the connectors to the outside world and some switches.
5	Antilog amplifier	this board contains the antilog amplifier (exponential converter) and CV multiplexer for the 6 DCO1 instances. This board is not present on the new production model, as the function is on the voice board there.
6	Correction-board	it seems this board corrects a bug on the CPU board of the old production model, as it is connected to the CPU board where one IC should have been. This bugfix is not present on the new production model.
7	CPU-board	here all the control logic comes together. It is not interchangeable with the NP version!
8	Voice-board	the tone generation happens completely on this board, all the analog circuitry (except the master clock, CV multiplexer and antilog amplifier) is found here. Not interchangeable with the NP version!
9	Power supply	a relatively simple +5V/+-15V power supply.

The new production model

The following boards are found in the new production model. My new models has a black power cable and i have seen another new model with a black power cable somewhere else.

1	Clock-board	contains the master oscillator and handles the joystick functionality.
2	Programmer-board	the main user interface to select and edit programs.
3	Assigner-board	controlling voice assignment and the arpeggiator.
4	Connector-board	contains the connectors to the outside world and some switches.
7	CPU-board	here all the control logic comes together. It is not interchangeable with the OP version!
8	Voice-board	the tone generation happens completely on this board, all the analog circuitry is found here. Not interchangeable with the OP version!
9	Power supply	a relatively simple +5V/+-15V power supply.

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