Model 3585A
p . Adjust A 1 5R7 for a marker reading of - 28 .0dBm .
q. Set the 3585A controls for I dB/DIV.
r. Again adjust A1 5R7 for a marker reading of - 28 .00dBm.
5· 1 8. Log Amp Slope Adjustment
a. Place the A14 board in the card nest.
NOTE
The Log amp linearity is affected by the card nest shielding.
Therefore, the procedure for adjusting the A 14 board is as
follows:
1 . Take a reading according to the instructions.
2. Remove the A 14 board (power should remain on).
3. Make a slight adjustment of the specified resistor.
(R43,R1 7,R8, R14,R21, R26)
4. Replace the A 14 board.
5.
Repeat until the required reading is obtained.
b. Set the 3585A controls for:
RECALL 601
INSTRUMENT PRESET
CENTER FREQUENCY . . . . . . . . . . . . . . . . . . . 350KHz
RANGE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . + 30dBm
REFERENCE LEVEL . . . . . . . . . . . . . . . . . . . . + 27dBm
dB/DIV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5dB
MANUAL SWEEP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . on
Set the synthesizer controls for:
FREQUENCY . . . . . . . . . . . . . . . . . . . . . . . . . . . . 350KHz
AMPLITUDE . . . . . . . . . . . . . . . . . . . . . . . . . . . -20.0dBm
c. Connect the 500 output of the Synthesizer to a 1 0dB/step attenuator. Connect the out
put of the attenuator to a 500 termination and the output of the 500 termination to A 1 7
J l
using the BNC to Sealectro adapter cable. Set the attenuator for 0dB o f attenuation . In
crease the amplitude of the synthesizer output until the Marker reading equals the Reference
Level ( = 27dBm) .
d. Set 3585A controls for:
OFFSET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . on
ENTER OFFSET
5-3 1