Hal Communications CWR6850, Инструкция по эксплуатации

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CHAPTER 4 PAGE 22
and releasing the "Y" key). A letter "Y" will appear on the status line indicating that the "word
mode" is active (between the "P" for printer on and the page number "1"). Now, type several more
words on the keyboard, separating each word with the space bar. Stop typing and notice that all
but the last word typed. Use the "BS" (Back Space) key to delete one letter at a time, up to the
first character position. Retype another word (no space bar yet); the word is displayed but not
transmitted. Now, hit the space bar; the whole word is now transmitted. Therefore, in "word
mode", the last word typed will be held until the space bar is hit.
Now, set the CWR6850 back to "continuous mode" be typing CTRL Y again ("Y" on status line dis-
appears) and set the lever switch to RECEIVE . Type four or five lines of text. Notice how only the
first three lines of text are shown on the screen. Switch to page 2 of the display using the [ PAGE ]
button (one press). Now all lines typed show on a much larger dotted area of the screen. Page two
shows all fifteen lines available for pretyped text plus the last three received lines of text and the
status line. You will probably use page 2 often if you precompose much transmit text. Cycle the
[ PAGE ] button four times and notice that other display pages, 0 and 3 may also be viewed.
Switch from [ MODE B ] to [ MODE A ] and notice that only pages 0 and 1 may be viewed. MODE
A is intended primarily for receive applications and MODE B will be used when you desire to both
transmit and receive. The extra lines on page 3 show the contents of the "HERE IS" memory chan-
nels and will be discussed in Section 4.3. The formatting of all four display pages is explained in
APPENDIX B. For the present, put the switch back to MODE B and select page 2 for display. Trans-
mit the text by selecting the SEND switch position. After the text has been transmitted, select
RECEIVE.
There are two ways in which the transmit-receive control of both the CWR6850 and the transceiver
can be done automatically. These are most easily demonstrated by using the RTTY mode. Set the
CW / RTTY switch to RTTY (button in). When transmitting, the RTTY tones will be heard through
the CWR6850 internal monitor (adjust volume with the VOLUME slide control). Leave "word mode"
turned off for now (CTRL-Y; no "Y" character on the status line).
The first of these techniques involves the CTRL-X key command (indicated by "X" on the status
line). To test the CTRL-X automatic operation, set the switch to RECEIVE and type several lines of
text. Now, put the SEND / AUTO / RECEIVE switch in the AUTO position and type CTRL-X. The
pretyped text will now start transmitting. While the text is being transmitted, type CTRL-X again.
The "X" will disappear from the status line, transmitting will stop and the RTTY tone will turn off.
Restart transmission with the command and let all the text be transmitted. Now, type more text;
notice that all letters are transmitted as you type them and that the RTTY tone continues. The
CWR6850 will remain in transmit mode for as long as CTRL-X is active ("X" on status line); you will
NOT receive text if CTRL-X is active. Also, the SW OUT - REMOTE control signal remains in trans-
mitter-on condition for as long as CTRL-X is active.
The second transmit-receive control uses the CTRL-A key command (letter "A" shown on status
line). To test this mode, make sure that all text is transmitted out of the transmit buffer using the
CTRL-X command or SEND switch position as explained above. Now, put the switch in the AUTO
position again and type CTRL-A ("A" appears on status line). Type a word and stop. Notice that the
RTTY tone turns on when you first start typing, the RTTY characters are transmitted after a short
delay and the single mark turns off after another short delay. Start typing again and the tone will
turn back on and transmit data for as long as there is text to be transmitted. The SW OUT - RE-
MOTE control signal is in transmit condition whenever you her the tone; a transmitter controlled by
this signal would be "on-the-air" during this time. The short delay of constant tone at the start of
transmission allows the transmitter and antenna control circuits and relays to "settle" to transmit
condition before data is released. This also allows the receiving station's autostart receive circuit to
activate. The delay at the end of the RTTY transmission helps to "smooth-out" variations in typing
speed, preventing multiple on-off transmitter operations as your typing speed varies. You will prob-
ably prefer to use "word mode" (CTRL-Y) when using the CTRL-A automatic control to assure that