Instructions for connecting the Optical Rotary encoder to my DDS-VFO

On my DDS PCB you will find in the lower left hand corner a large rectangular space marked "R-Enc" There are a total of 7 holes for the "normal" encoder. The two largest holes are for mounting and are connected to ground. The pair of holes on the left side are for the push switch, the lower one is connected to ground. The group of 3 holes on the left are for the encoder. The center one is ground. The other two are for the encoder pulse signal lines. Manufacturers Drawing This encoder is "900" series, "Style 0"

Here's how to connect the encoder.

The optical encoder has 4 conductor cable attached. The cable is gray, with one line painted black. Lets call the black line #1 which is ground. the next two are the encoder signal lines, and the last one is 5v power.

There will be a 4 conductor connector on the end of the cable. If you have the Aug 2009 version of the DDS PCB, you will also receive a 4 pin header you can solder on the back PCB, and the cable will plug into there. Optical Encoder Connector Closeup
Watch the polarity, the black wire on the cable is ground.

If you have an older version of the PCB, then you need to cut off the 4 pin connector and manually wire it.

This encoder will work OK with the default settings in the EEPROM. But it will work better if you make some changes since debounce logic is not need.

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