Test The Ecl Threshold - HP 1660C Series Service Manual

Test the ECL threshold

Select the field to the right of Pod A1, then select ECL in the pop-up menu.
1
On the function generator front panel, enter −1.160 V ±1 mV DC offset. Use the
2
multimeter to verify the voltage.
The activity indicators for pod 1 should show all data channels and the J-clock channel at a
logic high.
Using the Modify down arrow on the function generator, decrease offset voltage in
3
1-mV increments until all activity indicators for pod 1 show the channels are at a
logic low. Record the function generator voltage in the performance test record.
Using the Modify up arrow on the function generator, increase offset voltage in
4
1-mV increments until all activity indicators for pod 1 show the channels are at a
logic high. Record the function generator voltage in the performance test record.
Testing Performance
To test the threshold accuracy (logic analyzer)
3–13