TelePost LP-100A, Руководство по эксплуатации

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Detailed Operation
Operation of the LP-100A is straightforward, and designed to require a minimum of input once set up and calibrated. There are only
three buttons which are used in combination to access all the menus on the LP-100A. There are five main modes for the LP-100A,
which are accessed by momentarily pressing the “Mode” button. Pressing the button in mode 4 returns you to mode 1. The mode status
is saved in non-volatile memory, and the LP-100A will return to the saved mode upon powering up. There is also an automatic two-step
screen saver mode which dims the screen after approx. 30 sec of inactivity, and marches your call sign across the screen after approx.
2 min. of inactivity. This is done to extend the life of the GVFD display.
Mode
There are five selectable modes… Normal, Vector, dBm, Field Strength and Compression. A sixth mode which display relative power
and phase between phased array elements or stacked beams is in the works as well.
Normal mode is designed to display all the information you normally need on one screen. It displays power in three auto-ranging scales,
and SWR, plus bar graphs for both.
Vector
mode displays Z, Phase angle of Z, X and R. These values are relative to the “LOAD” connector, not the antenna. Antenna Z
can be calculated by knowing the feedline length and using a program like TLW, or a Smith Chart. Note: The LP-100A cannot
determine the sign of X automatically.
dBm mode uses professional dBm and RL (Return Loss) instead of watts and SWR to indicate power and load quality. The resolution
is 0.1 dB for both. The range is +15 dBm to +64 dBm, and RL from 0 to 49.9 dB.
Direct/Field Strength mode is similar to dBm mode except that it is calibrated to display power from
–15 dBm to +33 dBm. There is no
return loss in this mode because it does not utilize the coupler. Power is supplied directly to one of the inputs on the back of the LP-
100A.
This mode can be used for accurate low power bench measurements, as in checking the output to a transverter or the level of a local
oscillator of mixer. It is also very useful for doing antenna field strength measurements, as in checking a beam pattern. This requires
feeding a small pickup antenna to one of the inputs. The LP-100A could be set up in a field, connected to a laptop computer with wi-fi,
and the results can be read over the wireless LAN back in the shack. This eliminates any wiring that could distort the pattern.
NOTE:
The maximum power for the direct inputs is 2W.
Peak-to-Average Ratio displays the ratio of the peak signal to average level of the RF envelope. It is used to determine the
effectiveness of speech processing and compression equipment in your radio.
Alarm
The Alarm button is used to set the SWR alarm set point. There are 6 choices… OFF, 1.5, 2.0, 2.5, 3.0 & User. The User setting is
adjusted in Setup/CAL mode, and the programmed value
is shown next to the word “User” on the display. Holding the Alarm button will
advance the choices every half second or so. Tapping the button will put the Alarm in “snooze” mode for a minute. Tapping again
during tuning will reset the function for another minute. This allows adjusting an antenna tuner without the alarm going off, but it returns
to normal after tuning to protect the amplifier as intended. If “Avg. During Snooze” is selected for the W Mode SWR Display setting,
then entering Snooze mode will also make the SWR display average instead of peak until the timer times out. This makes antenna
tuning easier since you can stay in the W mode even during antenna tuning.