Heathkit SB-401 - Page 33

Page 108
METER READINGS
Refer to Figure 5-1, and study the meter scale,
Note how it reads for various positions of the
Meter switch, Observe that the meter has two
main scales and an ALC area, The scale
numbered from 0 to 10 is read directly for
relative power indications, For Grid Current
readings, each small scale division represents
.l milliamperes, For High Voltage readings,
each small scale division represents 100 volts,
The 0 to 500 scale is read directly to indicate
plate current in milliamperes, The meter scales
should be interpreted as follows:
Co.
RELATIVE
POWER
OUTPUT
REL PWR
READING
TRANSMITTER
FREQUENCY
To read the desired frequency, add the BAND
switch setting in epahe rs to the slide rule
pointer setting in hundreds of kilohertz and the
circular dial setting in kilohertz,
For Example: If the BAND switch is set to 3.5,
the slide rule pointer is between 2 and 3, and the
METER
SWITCH
MEASURES
SCALE
READING
POSITION
SS
FINAL GRID
D = &
Sexe FINAL PLATE 0 - 500 MA
CURRENT (Normal, 250 ma)
ALC AREA ONLY
POINTER SET
AT 0
LC
FINAL HIGH
Gg rearyxir
TOP EDGE OF ALC AREA REPRESENTS MAXIMUM
ALLOWABLE MODULATION DETERMINED BY
MICROPHONE LEVEL CONTROL
RELATIVE POWER
0-10
GRID CURRENT
O-1 MA
HIGH VOLTAGE
0-1000 VOLTS
PLATE CURRENT
0-S00 MA
FIGURE 5-1
RANGE OF READING
0-1MA
(Normal, 0-0.1)
MAXIMUM MODULATION
AT RIGHT EDGE OF
ALC AREA
0 - 1000 VOLTS
(Normal 700-800 volts)
ADJUSTABLE ZERO TO
MAXIMUM WITH REL
PWR CONTROL
circular dial is set to 53, the frequency is
3.753 MHz, If the BAND switch is set to 14,0,
the slide rule pointer between 0 and 1, and the
circular dial is set to 12, the frequency is
14,012 MHz,
Figure 1-2 (fold-out from Page 86) explains
each front panel control,