usually most convenient to normalize the LINEAR

h. Adjust VERTICAL GAIN to place maximum

SENSITIVITY vernier by setting it to "1" (blue scale).

signal amplitude exactly on LOG REF (top) graticule

line, Figure 4-2. Repeat Steps g and h to obtain

optimum adjustment of VERTICAL GAIN (increments as

a. Set the LOG/LINEAR switch to LINEAR. Set

close to one division per 10 dB step as possible).

LINEAR SENSITIVITY to 1 mV/div (1 mV x 1). Since

the -30 dBm calibrator output is = 7.1 mV (across 50

ohms), the CRT deflection should be 7.1 divisions.

b. Adjust AMPL CAL on 8553B for a 7.1 division

CRT deflection, if necessary. (LINEAR display is more

a. Set the LOG REF LEVEL controls to -30 dBm (-

expanded than the compressed LOG display, so

30 + 0).

adjustment of the AMPL CAL control can be made with

b. Adjust AMPL CAL so that the signal amplitude (-

more resolution in LINEAR without noticeable effect on

30 dBm) is exactly on the LOG REF (top) graticule line

the LOG calibration.) The analyzer is now calibrated for

of the CRT. The analyzer is now calibrated in the LOG

both the LOG and LIN display modes.

display mode.

RANGE- MHz ................................ .................... 0-110

SCAN WIDTH ................................ .......... .0-100 MHz

SCAN WIDTH PER DIVISION ........................ 10 MHz

calibrated in absolute voltage.

For LINEAR

BANDWIDTH ................................ .................. 10 kHz

measurements the LIN scale factors on the left side of

LOG-LINEAR ................................ ....................... LOG

the CRT and the blue color-coded scales of the LINEAR

LOG REF LEVEL ................................ .......... .-10 dBm

SENSITIVITY controls are used. The signal voltage is

the product (note lighted "x" lamp) of the CRT deflection

Perform tests in Table 4-2, Front Panel Checks.

and the LINEAR SENSITIVITY control settings. It is