[RTTY] microHAM & Kenwood TS-450s

Tom Osborne w7why at frontier.com
Sat Jul 9 11:04:50 PDT 2011

Hi Joe

You are true that it looks like it should be on, but it loses something in 
the translation :-)

I use my TS-450 all the time here in FSK and it's set to 'off'.  Default is 
on.  73

 > Hold down the 'm.in' key while turning on the radio.
 > Check menu number 38.  It should be set to 'off' for normal FSK.

If this is true (and I have no reason to doubt Tom), it is another
case in which a Kenwood manual provides incorrect information about
the operation of the radio.  The Kenwood manual states that "ON"
represents a "closed" contact (switch "on") for Mark.

   "When the FSK transmission key is shorted, you can change between
   space transmission (off) and mark transmission (on)."

     - TS-450S/TS-690S Instruction Manual, pg 53.

Almost every modern FSK interface provides an open collector FSK
output that is *closed* in Mark (pulled to ground) and *open* in
Space.  This is the same as the "simple" transistor on the output
of a serial port or USB to RS-232 converter for those using EXTFSK
with MMTTY.


    ... Joe, W4TV

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