Kenwood TK-840
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Kenwood TK-840 / TK840 information
Kenwood TK-840
TX: 425-500 RX: 435-495
Software only programs 450-488mhz. To override... Hex dump programming file. At offset 116: 01 E0 AE 00 B2 (ch 01, tx E0 AE, rx 00 B2) To get the bytes to edit into the file, use this formula: (freq + 109.6)/.0125 then convert to hex and reverse the bytes (e.g. B200 to 00 B2)
Front panel controls:
PWR, VOL-UP, VOL-DOWN, SYS-DOWN, SYS-UP, GRP-DOWN, GRP-UP, SCAN, AUX
PWR + SYS-UP = "PROGRAM" THEN PRESS AUX = "89EC" THEN PRESS SCAN = "PROGRAM_" PWR + SYS-UP = "PROGRAM" THEN PRESS SCAN = "PROGRAM_" PWR + GRP-DOWN = "UHF F1" "TUNING" "7-1"
PRESS SYS-UP/SYS-DOWN TO SELECT SYSTEM # PRESS GRP-UP/GRP-DOWN TO SELECT GROUP # THEN PRESS SCAN TO TOGGLE PROGRAM MODE: SYS-UP/SYS-DOWN TO SELECT PROGRAMMING OPTION (SQL,BAL,FQT,FDQT,FID,SENS,POWR,DEV) GRP-UP/GRP-DOWN TO SELECT SETTING, AUX TO SCROLL THROUGH OPTIONS, SCAN TO EXIT
PWR + GRP-UP = DISPLAY TEST THEN SHOWS SYSTEM/GROUP #
PRESS SCAN TO TOGGLE SPEAKER MUTE/UNMUTE PRESS AUX TO TOGGLE TALKAROUND PRESS SYS UP/DOWN & GRP UP/DOWN TO SELECT SYSTEM/GROUP
S G (G 1 THRU 8 ALL THE SAME) 1-1 467.500 2-1 467.075 3-1 468.850 4-1 469.075 5-1 469.500 RX 470.500 6-1 487.400 RX 487.500 7-1 487.900 RX 487.875
START RADIO NORMALLY IF PROGRAMMING WITH PC & RIB
Here is a description of how the PC/radio talk over the serial interface:
PC INTERFACE IS 1200 8N1 PC: TOGGLES CTS PC: "PROGRAM" RADIO: "<06><01>" PC: (ONE OR TWO-BYTE PASSWORD) RADIO: "" IF PASSWORD IS INVALID PC: TOGGLES CTS OR DOES SOMETHING ELSE TO RESET RADIO AFTER 3 INVALID PASSWORDS
RADIO REPLIES WITH MODEL # PC SENDS PASSWORD (0-10 UPPERCASE CHARACTERS AND/OR PUNCTUATION).
Raise RTS, send 11 bytes, drop RTS A = 04 41 FF FF FF FF FF FF FF FF FF
04 THEN PASSWORD PADDED WITH FF'S.
Get reply from radio. 15 = bad password.
chars decimal 32 thru 96
