Note

Note

RF Section

1.Low-Voltage Power Supply Adjustments

7.Verify that the + 120 V indicator AlA7DS2 (yellow LED) is lit.

On IF-Display Sections serial prefixed 3001A and below, indicator AlA7DS2 is a + 100 V indicator.

8.Connect the DVM to AlA7TP3. DVM indication should be + 120.0 ~k3.0 V dc. The + 120 V supply is referenced to the + 15 V supply; therefore, if the + 120 V supply is out of tolerance, a circuit malfunction is indicated.

On IF-Display Sections serial prefixed 3001A and below, the DVM indication should be + 100.0 62.0 V de.

9.Verify that the +5.2 V indicator AlA7DSl (yellow LED) is lit.

10.Connect the DVM to AlA7TP2. DVM indication should be +5.200 ho.050 V dc. The +5.2 V supply is referenced to the + 15 V supply; therefore, if the +5.2 V supply is out of tolerance, a circuit malfunction is indicated.

11.The +2OV indicator A24DS2 (yellow LED) should be lit. See Figure 3-4.

A24

V O L T A G E R E G U L A T O R

\

A24R60 +2OV A D J

I

AZ4R60

+2OV A D J

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

A24

Figure 3-4. Location of RF Section Low-Voltage Adjustments

12.Connect the DVM to A24TP3 with the ground lead to A24TPl. Adjust A24R60 +2OV ADJ for a DVM indication of +20.000 &O.OlO V dc.

13.The + 15V indicator A24DS4 (yellow LED) should be lit.

14.Connect the DVM to A24TP2. The DVM indication should be + 15.000 ho.050 V dc. The + 15V supply is referenced to the +2OV supply, therefore, if the + 15V supply is out of tolerance, a circuit malfunction is indicated.

15.The +5V indicator A24DS5 (yellow LED) should be lit.

16.Connect the DVM to A24TP5. The DVM indication should be +5.230 f0.050 V dc. The +5V supply is referenced to the +2OV

Adjustments 3-27