Marathon Computer V3.5 user manual Slidewire Board Calibration

Maintence and Troubleshooting

Unipro 3.5

time. Wait 5 to 10 seconds to allow the reading to record, then take it out of calibration mode by throwing the switch.

Remove the banana plugs from the simulator (remove the load from the line) and wait for the instrument to "max out" at 3500.

Let the reading settle at maximum (another 5 to 10 seconds) then reinsert the banana plug into the simulator to see if the instrument returns to a steady 1500 at all inputs.

Vary the input millivoltage down and verify that 1500 reduces to 1000 at a steady level for each input setting.

Check the reference voltage on TBD-5 and 6 (for input B) and 8 and 9 (for input C). Should read around +2 mV (between 1.8 and 2.2 is considered good).

Slidewire Board Calibration

Zero

Turn off the power at the simulator. Short the input by putting a banana plug shorting block into the simulator. Short the jumper ( switch) wired into 17 and 18 to calibration mode.

This will produce some value in the PROCESS window and Z-A in the SET window.

Use the left and right arrow keys to change the adjustment from coarse to fine in the PROCESS window, and the up and down arrow keys to change the value. Adjust the PROCESS window value to zero (0), or as close as possible.

Press the [Enter] key twice to store the value.

Rev. 11.00

December 30, 1995