Alinco DX-801 Bedienerhandbuch PDF herunterladen (Seite 17)

MFJ-925 Super-Compact IntelliTuner Automatic Antenna Tuner Instruction Manual

Miscellaneous

Antenna Memory

The “memory resolution” is the width of frequency spectrum that the tuner recognizes as being the same

as a tuned frequency already in memory. The memory resolution is approximately 0.1 percent of the

lower frequency of each amateur band. For example, the memory resolution on the 40-meter band (7000

to 7300 kHz) is 7 kHz; if the tuner has memorized a setting for 7050 kHz, it will automatically call up this

setting for any frequency from 7047 to 7053 kHz. Memory resolution is smaller at lower frequency to

accommodate the higher antenna Q and larger at higher frequency where the antenna Q is lower. The

memory resolutions for the HF amateur bands 160 through 10 meters are:

Meter Frequency Range (kHz) Memory Resolution (kHz)

160 1800 – 2000 2

75/80 3500 – 4000 4

60 5330.5, 5346.5, 5366.5, 5371.5 and 5403.5 5 memory locations

40 7000 – 7300 7

30 10100 – 10150 10

20 14000 – 14350 14

17 18068 – 18168 18

15 21000 – 21450 21

12 24890 – 24990 25

10 28000 – 29700 28

Table 2. Memory Resolution.

The memory resolution for non-amateur frequency bands between 160 and 10 meters is approximately

0.2 percent of the lower frequency of each band. There are two primary memory banks, each with four

secondary memory banks. Each secondary memory bank has 2500 memory locations. Tuner settings are

stored in memory separately in primary memory 1 and primary memory 2. This provides memory for up

to eight different antennas. See “ALT Button” on page 5. Defaults are memory banks 1A and 2A ON.

IntelliTune

Algorithm

When the tuner cannot find an appropriate setting in its memory, it begins its calculation function. It

measures the complex impedance of the antenna (load) at the transmitting frequency, then it calculates the

LC components needed for a match. Then it fine-tunes the components for minimum SWR. If for any

reason the tuner cannot calculate the load impedance, it proceeds to yet another method of calculation.

LC Limits

The upper limits of inductance (L) and capacitance (C) are factory-limited according to frequency and

maximum power rating; i.e., higher frequencies need less inductance and less capacitance when the L-

network is properly tuned. These limits are built into the MFJ-925 to prevent matching of extreme load

impedance outside the tuner’s specification, which may result in excess voltage and/or current across the

tuner’s components.

1 2 ... 12 13 14 15 16 17 18 19 20 21 22 ... 39 40

Keine Kommentare

Alinco DX-801 Bedienerhandbuch Seite 17