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DRO-550 Construction Guide (rev. 2)
18
Step 5. Install the Connectors
The scale connectors are 4 pin mini-DIN type that mount to the back panel with 4-40 x 1/2"
black machine screws. You can install up to five scale connectors with the DRO-550. The
connectors listed in the bill of materials have a hole on either side that must be tapped 4-40
before mounting with the screws. This is most easily done with a small hand tap.
After tapping, mount the scale connectors to the back panel with the 4-40 x 1/2" screws.
The edge finder and tachometer connectors are 3.5mm stereo jacks. The DRO-550 supports up
to two of each. Remove the nuts included with the connectors and mount them on the rear panel.
If MTA plugs are used on the other end of the cables, then they must not be installed until after
the stereo jacks are installed because the MTA plugs will not fit through the hole for the stereo
jack. Solder the wires to the stereo jack as shown in the
cable construction page
.