Agilent Technologies 856290216 service manual LC Bandpass Adjustments, TAM Connector Pin Locations

3. IF Bandpass Adjustment

Procedure

1.Turn the spectrum analyzer off by pressing @. Disconnect the power cord. Remove the spectrum analyzer cover and fold down the A2 controller, A3 interface, A4 log amp, and

A5 IF assemblies. Reconnect the power cord. Turn the spectrum analyzer on and allow it to warm up for at least 30 minutes.

2.Connect the negative DVM lead to pin 6 of A5J6. See Figure 2-5 and Figure 2-6. Set the HP 3456A controls as follows:

Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DCVOLTS Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1OV

3.On the spectrum analyzer press, (-1, l=), 2, LMHz), ICAL), and IF AD3 IX OFF so OFF is underlined.

PIN 2 . . • . . . . . PIN 16

PIN 1 n . . . • .m

SP114E

Figure 2-8. TAM Connector Pin Locations

LC Bandpass Adjustments

4.On the spectrum analyzer, press AD3 CURR IF STATE. Wait for the IF ADJUST STATUS message to disappear before continuing with the next step.

5.Read the voltage on A5TP5 (this is an empty-hole type of test point). If the voltage is less than t6.06 Vdc, turn A5L300 LC CTR 1 clockwise. If the voltage is greater than +6.26 Vdc, turn LC CTR 1 counterclockwise.

6.Repeat steps 4 and 5 until the voltage reads i-6.16 Vdc flO0 mV.

Note	If the range for the LC CTR adjustment is insufficient, replace the
	appropriate factory-selected capacitor as listed in Table 2-6. To determine
	the correct replacement value, center the LC CTR adjustment and press
	AD3 CURR IF STATE. After the IF ADJUST STATUS message disappears, read
	the DVM display. Choose a capacitor value from Table 2-7, based on the
	DVM reading and the presently loaded capacitor value. Table 2-10 lists a few
	capacitor part numbers.
Caution	Turn the spectrum analyzer off by pressing luNE) to the off position before
	removing or replacing any shield.

7.Move the positive DVM lead to A5TP6.

8.Adjust A5L301 LC CTR 2 by repeating steps 4 through 6.

9.Move the positive DVM test lead to A5TP2 (this is a resistor-lead type of test point).

10.Adjust A5L700 LC CTR 3 by repeating steps 4 through 6.

2-22 Adjustment Procedures