24.Track and Hold Adjustments

Reference

Description

A3A9 Track and Hold

The CAL OUTPUT signal is connected to the RF INPUT. The instrument is placed in zero frequency span to produce a dc level output from the IF-Video section and this dc level is regulated by adjusting the reference level. The Offsets and Gains on the Track and Hold assembly are adjusted for proper levels using a DVM.

SPECTRUM

ANALYZER

DIGITAL VDLTMETER

 

Figure 3-87. Track and Hold Adjustments Setup
Equipment

Digital Voltmeter (DVM) .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 3456A

Procedure

1. Place instrument upright as shown in Figure 3-87 with top and A3

 

Digital Storage covers

removed.

2.Set LINE switch to ON and press (INSTR PRESET].

3.Connect CAL OUTPUT to RF INPUT.

4.Connect DVM to A3A9TP3 and ground to A3A9TPl.

5.Key in CCENTER FREQUENCY) 20 MHz, ~FREQUENCY SPAN] 0 Hz.

6.Disconnect cable 7 (violet) from A4AlJl.

7.Short A3A9TPl to A3A9TP3, or use an SMB snap-on short to A3A9Jl. DVM indication should be 0.000 IfrO.001 V de.

8.Key in CRINGLE], TRACE A (CLEAR-WRITE],MARKER C-1, MARKER [nl, SWEEP (CONT), (SHIFT_) TRACE A (BLANK) e.

9.Adjust A3A9R59 (T/H) OFS until MARKER A level indication as indicated by CRT annotation flickers back and forth between .OO and .lO dB. See Figure 3-88 for location of adjustment.

3-142 Adjustments