HP 415E User Manual

Model 415Е
Section ІП
Paragraphs 3-15 to 3-21
Table 3-1. Panel Descriptions
1. Selects desired 415E power source: BATTERY/
CHARGE position allows internal battery re-
charge when power cordis connected to AC line,
2. Indicator lights when power switch is in LINE/
ON or BATTERY/CHARGE position.
Female BNC INPUT connector.
4. Set input of Model 415E for use with a bolom-
eter or crystal detector mount. See Paragraph
3-53.
5. Adjustment allows center frequency variation
by 70 eps.
6. Attenuator adjusts gain in 10 db steps.
7. Allows full scale expansion of any 2.0 db portion
of the 10-db scale.
Changes bandwidth from 15 to 130 cps.
9. Allows initial meter reference setting with a
control range of at least 10-db.
10. Provides fine adjustment of GAIN control meter
settings.
11. Mechanicalzero adjustment allows exact sett-
ing of meter needle to 2.0 db calibration mark.
12. With POWER switch set to BATTERY/TEST, a
meter needle indication within the "BATTERY
CHARGE" area on the meter face (indicated ру
12A) shows that internal battery is charged suf-
ficiently for proper 415E operation; if needle
indicator is to left (area 12B) of "BATTERY
CHARGED" area, then battery is not charged
sufficiently for proper instrument operation
(option 01 - ONLY).
13. Additional input connector (wired in parallel
with front panel connector); supplied as Option
02 for 415E only upon request.
14. DC output for recorder use (0to1voltinto open
circuit or 1000 ohmg.
15. AC output for use as tuned amplifier output.
16. Three-conductor AC power cord receptacle
(NEMA-type).
17. Contains power line fuse.
18. Slide switch to allow 115- or 230-volt AC
operation.
3-15. SWR MEASUREMENT EQUIPMENT
AND TECHNIQUES.
3-16, EQUIPMENT.
3-17. A typical setup of equipment used in SWR meas-
urements is shownin Figure 3-3. The signal source is
usually square-wave modulated at 1000 cps since other
modulating waveforms often cause undesirable fre-
quency modulation of the source. Harmonics from the
Source sometimes cause trouble andcanbe eliminated
with а low-pass filter.
3-18, The detector shouldbe а square-law device (out-
put voltage proportionalto RF power input) such as a
barretter or a crystal diode operated at low signal
levels. The meter of the 415E is calibrated for square-
law detectors. Crystal diodes are normally more sen-
sitive than barretters but barretters are square-law
over a wider dynamic range. Both types of detector
normally maintain accurate square-law responseupto
at least fullscale deflection with the RANGE-DB switch
set to 30 position and coarse GAIN at maximum. (1 хау
RMS sine wave or 2.2 mv peak-to-peak square wave
causes full scale deflection on HIGH. XTAL IMPED
position. On other positions of INPUT switch, 0.15 mv
RMS sine wave or 0.33 mv peak-to-peak square wave
causes full scale deflection.) Above this level these
detectors should be individually checked for departure
from square-law behaviour or manufacturer's data
should be consulted,
02152-3
3-19. A short circuit termination is useful in establish-
ing reference positions along the transmission line and
is measuring transmission line wavelengths.
3-20, SLOTTED LINE PROBE PENETRATION.
3-21. Ageneralrule in slotted line measurement is to
use minimum probe penetration that still picks up ad~-
equate signalto measure. The probe couples to the
@ MODEL 415E
SIGNAL
GENERATOR
ATTENUATOR
—
UNDER
TEST
СС
4iSE-B-4
| й DETECTOR LOAD
SLOTTED LINE
Figure 3-3. Typical SWR Measurement Setup
3-3

HP 415E Specifications

General

Brand	HP
Model	415E
Category	Measuring Instruments
Language	English