Note
QST, Mar 1980, p. 179.
QST, Apr 1981, p. 127.
QST, Jan 1982, p. 159.
The ROBOT Model 800 is a complete communications terminal for sending and receiving Baudot, ASCII and Morse Code. In addition, the Model 800 generates alphanumeric character displays for use in Slow Scan Television. and transmits this information in the amateur SSTV format. The Model 800 is a microprocessor based system utilizing the 8085 Microprocessor, 6144 bytes of ROM, and 2560 bytes of RAM.
An intel 8251 USART is used for serial I/0 and intel 8155's are used for parallel I/0 and keyboard interface.
The Model 800 can be interfaced directly to the audio input and output jacks of communications equipment. It has a built-in terminal unit for demodulation of incoming Morse and RTTY signals as well as an audio frequency shift keyer for transmission. A standard closed circuit television monitor is used for the display and is connected directly to the Model 800 Terminal.
Specifications
– AUDIO INPUT: 20 millivolts to 3 volts; 600 ohm impedance.
– AUDIO OUTPUT: 0 to 2 volts adjustable; 600 ohm impedance.
– VIDEO OUTPUT: Standard TV video signal 1.4 volts p-p white positive into 75 ohms, compatible with standard 525 line CCTV monitor (625 lines in 50 Hz countries).
– TTY LOOP KEYER OUTPUT: Transistor switched current loop keyer.
– CW KEYER OUTPUT: Transistor switched to ground for cathode or grid-block keying.
– PTT OUTPUT: PTT line switched to ground during transmit.
– SCOPE OUTPUTS: Separate discriminator outputs for oscilloscope monitoring.
SIGNAL CHARACTERISTICS
– BAUDOT: 7.5 unit code (1 start, 5 data, 1.5 stop) A-Z, 0 to 9, `!"#$&'(): BELL;, 1?/`; CR, LF, LTRS, FIGS. SPEEDS: 60, 66, 75, 100, 132 WPM.
– ASCII: 110 Baud, 11 unit code (1 start, 8 data, 2 stop) A-Z Upper and Lower case, 0 to 9, `!"#$%&'()* = -'@ BELL+; []< ..?/`.
– TONE FREQUENCIES: IARU Low Tone Pairs (Model 800): 170Hz Shift: 1275Hz Mark, 1445Hz Space; 850Hz Shift: 1275Hz Mark, 2125Hz Space.
– High Tone Pairs (Model 800H): 170Hz Shift: 2125Hz Mark, 2295Hz Space; 850Hz Shift: 2125Hz Mark, 2975Hz Space.
– MORSE: International Morse Code, A-Z, 0 to 9, `.,?:;-/`, AR, AS, BT, KN, SK.
– SSTV OUTPUT: Crystal controlled SSTV Audio-FM 1200 Hz Sync, 1500 Hz Black, 2300 Hz White, 3.0 volts p-p (adjustable) into 600 ohm load. Horizontal sync 6 ms., vertical sync 66 ms. (Notice: The Model 800 does not receive SSTV pictures. An SSTV Scan Converter such as the Robot Model 400 is required for this purpose.)
TRANSMIT MODES
BAUDOT, MORSE, ASCII
Continuous: Transmits each character as it is entered on the keyboard.
Word: Transmits whole word when space bar is depressed.
Line: Transmits entire line when complete.
Editing: Delete key causes backspace and erases previous character.
Tune: Locks CW Keyer Output for transmitter tuning.
Transmit Text Buffer: 511 characters.
Automatic CR, LF: Prevents splitting of words at the end of each line.
SSTV
– Display: Real time display of transmitted text. 36 or 18 characters (6 lines of 6 characters or 3 lines of 6 characters).
– Cursors: "Winking" cursor indicates the next character position. Line cursor indicates which portion of the display is being transmitted.
– Editing: Cursor controls include up, down, left, right and home to top of screen. CLEAR function causes the entire display to be erased and "homes" cursor.
– Fractional Frame: LINES function changes the number of character lines transmitted. Operator may select from 1 to all 6 lines.
– Reverse: Causes display to change from normal black on white to white on black.
– Test Patterns: 6 bar gray scale and checkerboard.
PROGRAMMABLE FEATURES
– WRU: 8 character programmable WRU code. The Model 800 responds to valid code by transmitting one of its HERE IS messages.
– SELCAL: 8 character programmable SELCAL Code. The Model 800 responds to receipt of valid code by copying the message immediately following the code into display memory.
– HERE IS: 2 programmable 64 character HERE IS message memories.
– ID: Programmable 8 character ID memory.
– AUTOMATIC CQ: A CQ message can be accessed which automatically inserts your call letters from the programmable ID memory.
OTHER FEATURES
– DISPLAY: 72 characters per line; 11 lines received text, 11 lines transmit text (split screen mode); 24 lines total (full screen mode): 5 x 7 dot matrix (except in SSTV mode).
– UNSHIFT ON SPACE: Automatically returns terminal to letters mode when space is sent or received.
– KEYBOARD TRANSMITTER CONTROL: Complete transmit control via PTT line.
– SIDE TONE OSCILLATOR: Audible side tone oscillator can be enabled for code monitoring. Volume is adjustable via rear panel control.
– MORSE TRAINER: Automatically sends random 5 letter groups at selected speeds (1-99) WPM.
– ON SCREEN STATUS INDICATOR: Status line shows all operational modes, shifts, and data rates which are in effect.
– ON SCREEN TUNING INDICATOR: "Plus-Plus" type, displayed as a moving bar in the status line. Displays relative outputs of the discriminator filters.
– MORSE AUTO TRACK: Tracking of received Morse code is totally automatic over the entire range of 4 to 99 WPM.
– TEST MESSAGES: RY and "Quick Brown Fox" test messages.
DEMODULATOR
– DUAL TWO-TONE ACTIVE FILTER DISCRIMINATOR
– SHIFT FREQUENCIES: 170 Hz, 850 Hz.
– AUTO START RESPONSE TIME: 2 seconds.
AUDIO FREQUENCY SHIFT KEYER
– TYPE: Phase coherent crystal controlled.
– DISTORTION: All harmonics below the 15th are 50 db down.
– STABILITY: Crystal controlled to plus or minus .025%.
CONNECTORS / CONTROLS
– KEYBOARD: 55 key alphanumeric array, two-shot molded keytops, matte grey finish, tilted keys.
– TO MONITOR: Is a BNC video output connector for connection of fast scan monitor display.
– TTY LOOP: Is a phono connector for connection of peripheral TTY equipment to the loop keyer output.
– SCOPE MARK and SCOPE SPACE: Are phono connectors for connection of an oscilloscope display to the discriminator outputs.
– FROM RCVR: Is a phono connector for inputting audio to the Model 800 from the station receiver audio output or from the Model 400 SSTV Converter.
– AUX OUT: Is a phono connector auxiliary output jack for connection to an audio tape recorder or the Model 400 SSTV Scan Converter.
– TO XMTR: Is a three conductor 1/4-inch jack. One conductor is used for the push to talk line which is grounded during transmit. The other two conductors are for audio and ground.
– OUTPUT LEVEL: Is a control which sets the audio output level between 0 and 2 volts.
– TO CW KEY: Is a 1/4-inch three conductor jack for connection to the transmitter CW key input.
– SIDE TONE: Is a control which sets the volume level of the audible side tone oscillator.
Power Requirements: 105 to 125 VAC or 210 to 250 VAC (specify) and 50 or 60 Hz (specify). Power consumption 10 watts.
References
Review. QST, Apr 1982, p. 48.