The conveyor accessory is just a long conveyor, about three feet long. One end holds a power supply unit and a stepper motor to run the belt and a simple control board that controls the speed and direction of the conveyor. Because of the power supply the whole thing weighs abut ten pounds, and combined with its size, makes it a little awkward to move around and store.
On the side there is a fuse receptable and a power switch.
Strange, the fuse rating isn’t marked.
Inside the control box you can see the toroidal transformer in the back, the stepper motor (mounted on slots to adjust the belt tension), and the circuit board.
I do not know what U1 is. I pried off the heatsink, and from what I could make out the part number is UCN4204B. U2 is a 74LS08 quad AND gate, one being used to gate the clock signal. U3 (next to the small blue 4.7µF timing capacitor) is a 555 timer set up as an oscillator.
Someone had green yellow-wired the back of the circuit board to fix a routing error.
The pin on the bottom was supposed to be connected to +5V, but it was routed to GND by mistake. The trace had been carefully cut (due to the proximity of the nearby pins) and the yellow wire connected to it and the OUT pin of the voltage regulator.
The back of the control panel contains some point-to-point wiring to connect all the banana jacks and switches to the ribbon cable from the main circuit board.
The direction, clock enable, and motor power enable switches are wired with the center pin connected to the input of a control signal (pulled up by a 10kΩ resistor on the board) with one side connected to ground and the other connected to the banana jacks next to the switch to allow remote control by shorting the two jacks to each other with a relay. I really don’t know what the 10µF capacitor is for – debouncing, perhaps?
