Still MORE Observations - KC2CT - 07-05-91
  ------------------------------------------
  Well if you've been following this brief series, you probably
  know by now, that despite any criticism, I really LOVE my 850S!
  I've really dug into the guts of the radio, and truly find it
  a pleasure to explore and operate..Well here's a few other
  items that should be of interest to other hams:

. ALL BAND TRANSMIT
  -----------------
  Kenwood markets this radio worldwide, and has made provisions
  to allow the radio to transmit between 1.625 mhz and 29.999 mhz.
  I am providing this modification for INFORMATIONAL PURPOSES ONLY!
  DO NOT TRANSMIT OUT OF BAND, THIS WILL JEAPORDIZE YOUR LICENSE,
  AND HAVE THE FCC, AND/OR INTERNATIONAL AUTHORITIES KNOCKING AT
  YOUR DOOR!!!

  The All-band transmit modification requires the removal and re-
  location of a diode on the the digital board which is located
  behind the front panel.  The US version of the radio has diode
  D11 installed, and diode D9 removed.  D11 must be removed, and
  installed in the D9 position.  This modification IS NOT for the
  faint of heart, as it entails removing the front panel, and the
  digital board.  Note that the digital board has solder holes that
  are through-soldered; that is, there are circuit traces on both
  sides of the board, so make sure that ALL solder is removed from
  the holes.  This modification will also allow the antenna tuner
  to tune anywhere the receiver is tuned.  This modification should
  ONLY be performed by those familiar with soldering and de-soldering
  techniques, and requires patience, and dexterity.

. Broadcast Band Sensitivity
  --------------------------
  BCB sensitivity REALLY suffers as a 24db attenuator is inserted
  when band-switched.  This attenuator circuit is very similiar to
  the TS-430/440.  Possible modification?

. Additional Front Panel Functions
  --------------------------------
  Pressing SCAN + TX-M.CH will set the radio into its extended
  function mode.  These options can be scrolled via the M.CH/VFO CH.
  switch.  The following are the extended functions:


  00 - This is the ROM Checksum displayed as a 4-digit hexadecimal
       number  This cannot be changed.

  01 - Allow filter selection in transmit. Initially set OFF.

  02 - Antenna tuner power down.  Initially set to OFF.

  03 - Antenna tuner non-stop mode.  When set to on, the antenna
       tuner will not stop when the lowest VSWR is found.  Initially
       set to OFF.

  04 - Store mode, and filter settings prior to changing bands, or
       channels.  Initially set to ON.

  05 - Display -HELLO- on digitial display, and send it in Morse
       code on power up.  Initially set OFF.

  06 - Turn full LCD display ON on power on.  Initially set OFF.

  07 - Turn Subtone ON or OFF.  Initially set ON.  Note that even
       when set off, the TONE indicator will be lit on the display.

  08 - Unknown. Initially set OFF.
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Note: I haven't tried or verified any of this, proceed at your own
risk.  And do not transmit outside of legal bands.  WA2ISE


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