Yaesu FT-950 Operating Manual

Also see for FT-950: Brochure & specs Reference Manual Update Update

Page 101FT-950 O PERATING M ANUALMost RTTY operation today is accomplished using a TNC or other computer-based system that utilizes AFSK tones. Assuch, the previous discussion on LSB-mode “Packet” operation will apply for Baudot operation, as well. For RTTY opera-tion using a Terminal Unit (TU) or the “FSK” output from a TNC, please see the discussion below. See also the illustrationfor details regarding connection to your TU.SETTING UP FOR RTTY OPERATIONBefore commencing RTTY operation, please direct your atten-tion to the setup steps shown in the chart to the right.BASIC SETUPRTTY (RADIO TELETYPE) O PERATION1. To engage RTTY operation using “LSB” injection,which is generally used in the Amateur service. Pressthe [RTTY/PKT] button repeatedly until both the“ ” and “ ” icons appear on the display.2. To switch to USB-side injection in RTTY, press andhold in the [RTTY/PKT] button. Both the “ ” and“ ” icons will appear on the display.3. When you begin typing on your TU or computer key-board, the command to transmit should automaticallybe sent to the transceiver, causing it to enter the trans-mit mode.NOTE:If you anticipate making data transmissions of longer thana few minutes, we recommend that you reduce the trans-mitter power to 1/3 ~ 1/2 of its normal maximum via theMenu item “111 TGEN TX PWR111 TGEN TX PWR111 TGEN TX PWR111 TGEN TX PWR111 TGEN TX PWR”.ADVICE: If you need to adjust the output level from the “DATAOUT” pin (pin 5) of the RTTY/PKT jack on the rearpanel of the transceiver, please use Menu item “061061061061061RTTY OUT LVLRTTY OUT LVLRTTY OUT LVLRTTY OUT LVLRTTY OUT LVL”. For the input level from the TU, thereis no adjustment of the FSK input level (Pin 4) of theRTTY/PKT jack. Please make any needed level ad-justments at the TU side.TO1 ANT DC IN2FROMGND ROT LINEAR TUNER PTT REC REM KEYDMU CATEXTSPKRINPUT: DC 13.8 V22 A-TUNE -TUNEAFIN PTTFSKOUTFSK INDATA OUTDATA PTTGNDTUN.C.GNDPTTFSK OUTAF INN.C.RTTY/PKT JACKDATA IN (Pin 1)Pin 6GND (Pin 2)DATA PTT (Pin 3)FSK IN (Pin 4)DATA OUT (Pin 5)SQL OUT( )MENU I TEM AVAILABLE VALUES059 RTTY R PLRTY nor (normal) / rEU (reverse)060 RTTY T PLRTY nor (normal) / rEU (reverse)061 RTTY OUT LEL 0 ~ 100062 RTTY SHIFT 170/200/425/850 (Hz)063 RTTY TONE 1275/2125 (Hz) The Mark/Space Shift utilized in most Amateur RTTYoperation is 170 Hz. Other shifts may be configured,however, using Menu item “062 RTTY SHIFT062 RTTY SHIFT062 RTTY SHIFT062 RTTY SHIFT062 RTTY SHIFT”. TheFT-950 is set up for “high tone” operation (centeredon 2125 Hz) by default, but you may configure it forlow tone (1275 Hz) operation using Menu item “063063063063063RTTY TONERTTY TONERTTY TONERTTY TONERTTY TONE”. You may find that you are unable to decode some RTTYstations, even if they are of sufficient signal strength.If this is observed, there may be a Mark/Space polarityproblem between your station and the other station. Ifso, try setting Menu item “059 RTTY R PLRTY059 RTTY R PLRTY059 RTTY R PLRTY059 RTTY R PLRTY059 RTTY R PLRTY” to“rEUrEUrEUrEUrEU” (“Reverse”) to see if that permits copy. A sepa-rate Menu Item permits reversal of your transmitter’sMark/Space polarity: “060 RTTY T PLRTY060 RTTY T PLRTY060 RTTY T PLRTY060 RTTY T PLRTY060 RTTY T PLRTY”.QUICK POINT:In the FT-950, “RTTY” is a mode defined as being an“FSK” mode, whereby the closing and opening of a key-ing line (to ground) causes the Mark/Space tones to alter-nate. The RTTY mode is not an AFSK based mode in thistransceiver, and the AFSK output tones from a TNC willnot cause Mark/Space shifting to occur. Use the “Packet”mode for AFSK-based Baudot and other data modes.