22.Place jumper A14J23 in the NORMAL position and reconnect W34 to A15A2Jl.

23.Set the HP 8560A to the following settings:

CENTER FREQ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .300 MHz SPAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . OHz

24.Place jumper A14J23 in the TEST position.

25.Disconnect W32 from A15JlOl. Monitor the Sampler IF output (A15J101, SAMPLER IF) with a synthesized spectrum analyzer such as an HP 8568A/B or HP 8566A/B.

26.The Sampler IF should measure between 74 MHz and 114 MHz at -15 dBm to +2 dBm. If the signal frequency or amplitude is incorrect, refer to “Unlocked Offset PLL” in this chapter.

27.Set jumper A14J23 in the NORMAL position. Reconnect W32 to A15JlOl.

Note

The All YTO has an initial pretune accuracy of f20 MHz. However,

 

when the Roller Oscillator frequency is <73 MHz, this is changed to

 

-l-30/--10 MHz. If the Roller Oscillator is >93 MHz, the accuracy is changed

 

to +lO/-30 MHz. This is done by changing the Main Coil Coarse DAC to

 

keep the Sampler IF within the acquisition range of the YTO Loop. When

 

dealing with the Sampler IF and an unlocked YTO, the same frequency

 

differences apply to the Sampler IF.

 

 

28. Set the HP 8560A to the following settings:

CENTER FREQ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .300 MHz SPAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . OHz

29.Connect an RF signal-generator’s output to A14J501. Set the signal generator to the following settings:

Frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...84 MHz Amplitude . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..OdBm

30.Monitor A14J17 pin 1 with a DVM or oscilloscope.

31.As the signal generator’s frequency is increased to 104 MHz, the voltage at A14J17 pin 1 should change from f8.2 to -8.2 Vdc fl V.

32.Set the signal generator to the following settings and repeat step 23.

Frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...84 MHz Amplitude . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -15 dBm

Synthesizer Section 1 O-29