17. Pilot Second IF Amplifier Adjustments

 

 

A9 P I L O T

 

A10 P I L O T

 

 

 

2ND I F A M P L I F I E R

3RD

C O N V E R T E R

 

 

 

\

I

/

 

 

269MHz BANDPASS F I L T E R

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Figure 3-68.

Location of 269 MHz Bandpass Filter Adjustments

3 dB Point

> 2 1 MHz -4

Figure 3-69.

269 MHz Bandpass Filter Adjustments Waveforms

15.On the scalar network analyzer, press [CURSOR) MAX. Press cursor A, ON and set the cursor to the -3 dB point on the low side of the filter response (fO.1 dB).

16.Press cursor A and set the cursor to the -3 dB point on the high side on the filter response. The cursor A should read 0 kO.1 dB.

17.Press @ on synthesized sweeper and set to three divisions down (3 dB) from top of bandpass filter response. Press (M4) and set to three divisions down on opposite side of bandpass filter response.

18.Press MKR A on synthesized sweeper. M3-M4 should be greater than 21 MHz.

19.Disconnect cable 80 (greyblack) from A9Jl and cable 81 (greybrown) from A9J2 and reconnect instrument cables.

3-118 Adjustments