Trigger Input; Period Generator; Check For The Supply Voltages; Check The Current Sources For The Period Generator - HP 8114A Service Manual

Trigger Input

Period Generator

Delay Generator

Power Supply Voltages on the Timing Board
from a 50 0 source to the trigger input.
2. At the junction of R313, and R314, or at pin 7 of U304 a typical
voltage should read 1.75 V.
3. Program + 10 V trigger input threshold in the TRi!T;GEF:
display.
4. Check that at U302A pin 1 there is a typical voltage of
at U304 pin 9 a typical voltage of + 1.7 V.

Check for the supply voltages:

1. U407 pin 1 for + 12 V, and 1J407 pin 3 for + 5 V.
2. U402 pin 2 for -12 V, and U402 pin 3 for -5.2 V.

Check the current sources for the period generator:

1. Check pin 3 of U406, voltage regulator, for + 12 V.
Check
2. pin 2 of U406 for +8 V.
3. Varying the frequency from 1.01 MHz to 10.0 MHz the voltage at
pin 1 of U404A should vary from -0.5 V to -5.0 V.
4. Check for the following voltage drops across R402:
Check for the supply voltages:
17502 pin 2 for -12 V, and U502 pin 3 for -5.2 V.

Check the current sources for the delay generator:

1. Varying the delay from 0.00 ns to 999 ns the voltage at pin 8 of
HP 8114A Service Guide
mode
3.3 V, and
Troubleshooting 5.13