Model 3585A
Adjustments
Figure 5·20. Step Phase Detector Board (A26)
v. Reconnect the proper cable to A23 J l (A23 J l to A26J2) .
U p per Frequency
Limit R 7 5
w. Verify that the "STEP " and "SUM" lights on the A34 board go on when the A26J3
cable is disconnected.
x. Reconnect the proper cable to A26J3 (A26J3 to A2 1 J6) .
y . Set the 3585A controls for:
INSTRUMENT PRESET
RES. BW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3KHz
SWEEP TIME . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 sec.
z. Verify that the frequency counter is now changing in I MHz increments from 98MHz to
1 38MHz.
aa. Reconnect the proper cable to A23J2 (A23 J2 to A25J3) . This completes the L .O . Step
Loop Adj ustments .
5· 1 5. First L.O. VTO And Sum Loop Adjustments
a. Turn the 3585A power off. Place the First L.O. VTO (A22) on a PC extender board
and turn the power back on.
b. Set the 3585A controls for :
RES . BW HOLD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ON
CENTER FREQUENCy . . . . . . . . . . . . . . . . . . . . . . OHz
FREQUENCY SP AN . . . . . . . . . . . . . . . . . . . . . . . . . OHz
CF STEP SIZE . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40MHz
RES . BW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30KHz
5-25