TB 9-6625-152-24
(61) Set RF power amplifer gain to 50%. Set signal generator frequency to 10 MHz
and output to -45 dBm. Slowly increase signal generator output and, if necessary, power
amplifier gain for a measuring receiver indication of +20 dBm.
(62) Use TI [ ], [ ] keys to highlight 10 MHz calibration point on displayed table.
(63) Use TI front panel rotary knob to change TI power indication displayed on
bottom of TI screen to match measuring receiver indication.
(64) Use TI [ ], [ ] keys to highlight next calibration point on displayed table.
(65) Set signal generator frequency to required calibration point frequency and
output to -45 dBm. Slowly increase signal generator output and, if necessary, power
amplifier gain for a measuring receiver indication of +20 dBm.
(66) Use TI front panel rotary knob to change TI power indication displayed on
bottom of TI screen to match measuring receiver indication.
(67) Repeat technique of (64) through (66) above for remaining calibration points in
TI displayed table.
(68) Press TI [Return], [Calibrate] then [Store Cal] keys.
(69) Set all outputs to minimum and disconnect equipment setup.
(70) Perform paragraph 23 a above.
ADJUSTMENT PROCESS
24. Preliminary Instructions
a. Disconnect TI from power source and remove outer cover by removing six screws in
rear holding metal case to frame.
b. Slide metal cover until it is clear of frame.
c. Apply power to TI and allow 30 minute warmup.
NOTE
A number of the adjustments require access to the calibration
or diagnostics screens. These are normally locked but can be
unlocked to allow service access. The locking is re-applied when
the 2947A is powered down. To gain access to the calibration or
diagnostics screens, proceed as follows; Press the [HELP
SETUP] key. If the message Locked appears adjacent to the
[Calibrate] and [Diagnostic] keys, they must be unlocked
Press [Diagnostic] or
before access can be obtained.
[Calibrate]. The message ENTRY CODE will appear. Key in
the digits 2, 9, 4, 5, and then press the [dBm/ENTER] key. If
the procedure has been carried out correctly the Locked
message will be removed, and the [Calibrate] and
[Diagnostic] keys will now be active.