Time Base Stability - TB-9-6625-2215-350013

TB 9-6625-2215-35

b. Mount a calibrated TD-1209/U (Hewlett-Packard, Model 5300A) measuring system

on TI and orient the interconnected units upside down.

c. Connect measuring system to autotransformer and connect autotransformer to a 115 V

ac source.

d. Adjust autotransformer output for 115 V.

e. Adjust measuring system SAMPLE RATE control cw to ON position and allow 1

hour for warm-up.

f. Set INT STD-EXT STD switch on rear panel of frequency counter to EXT STD.

21. Time Base Stability

NOTE

Some models do not have an internal oscillator. When calibrating

these models, omit this check.

a. Performance Check

(1) Connect frequency counter A input to TI OSC jack (rear panel).

(2) Adjust Y1 adjustment (fig. 1) as required to obtain frequency counter indication

of exact frequency stamped on TCXO case (fig. 1).

Figure 1. Test instrument - (Hewlett-Packard, Model 5303B) - bottom view.