Timewave DSP-232, Operating Manual

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Chapter 9 AMTOR Operation
EAS — E cho A s S ent—is used in ARQ AMTOR. With
EAS ON
, you’ll see characters echoed to your screen only
after the other station has validated them; the characters appear on your screen three at a time. This allows you to
observe the progress of your transmission. If progress is very slow or jerky—most likely due to deteriorating
atmospheric conditions—then it’s probably time to wrap up the contact.
For this reason, you should set your own
AAB message to DE ( callsign ) ( MYSELCALL ) ( MYIDENT ) . If you turn
WRU ON
, your DSP will automatically send your
AAB
message when another station requests your identity.
Speed Change
In accordance with FCC Part 97.69 and international regulations, AMTOR is operated at 100 bauds. The DSP does
not permit any other speed.
WORDOUT
Some AMTOR users like to have their words sent out only when they’re complete, rather than individual letters sent
as they’re typed. Turning
WORDOUT ON enables you to edit the word you’re currently typing as long as you
haven’t pressed the (
SPACE
) bar or any punctuation.
Operating on the “Wrong” Sideband
By convention, AMTOR is used while in LSB. If you find a station operating on USB, you can reverse your receive
“sense” with
RXREV to copy him. Likewise, if someone tells you that you are on the wrong sideband you can
correct your transmit signal sense using
TXREV
, but ideally you should just switch to LSB and adjust your
frequency accordingly.
Letters and Figures Case
In the “old days” a key was used on mechanical teletype machines to differentiate between numbers, letters and
punctuation since AMTOR is limited to 32 different characters. The DSP takes care of that automatically so no
separate keybord stroke is required.
Function Keys
The following immediate commands and “Function Keys” are included for AMTOR operating convenience:
ARQ (SELCALL) Starts mode A selective call and forces Converse.
FEC Starts mode B transmission and forces Converse.
SELFEC (SELCALL) Starts Selective mode B transmission.
R Stops sending immediately, forces AMTOR Standby, clears the transmit
buffer of all remaining data.
AM Stops transmission, forces AMTOR Standby, clears the transmit buffer of
all remaining data.
AL Forces re-synchronization in ALIST (AMTOR mode A Listen).
L Forces LETTERS case.
N Forces FIGURES case.
Function Keys embedded in transmitted text:
(
CTRL-B
) Sends your AAB string as a “HERE-IS” message
(
CTRL-D
) Stops sending when the transmit buffer is empty
( CTRL-E ) Sends a "Who Are You? (WRU)" request to the other station
(
CTRL-F
) Sends callsign in Morse and shuts off your transmitter
( CTRL-N ) Sends FIGURES character
(
CTRL-O
) Sends LETTERS character
( CTRL-T ) Sends the time if the DAYTIME has been set; the date if DAYSTAMP has been set.
Switching Time Problem?
For operation in AMTOR ARQ, your transceiver or transmitter-receiver combination must be able to change
between transmit and receive within 20 mS. Most modern solid state radios can easily meet this specification. Many
older tube-type radios that use electromechanical relays also operate very well in AMTOR ARQ.
9-6 September, 05