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Mods Database
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KENWOOD TH-21 series HT TNC Interconnection
The following is a suggested circuit for
connecting a packet TNC
to a Kenwood TH-series HT. Included is the TH-21/31/41, the TH-
205/215/315/415, and the new TH-25/45 series HTs.
The connections are as follows:
A sub-miniature plug is used for receive audio. The tip of
this plug is audio out; the sleeve of this plug is the
common ground for PTT, transmit audio, and receive audio.
A miniature stereo plug is used for transmit audio and PTT.
Connect the middle "ring" of the plug to the TNC audio out
through a 0.2 uf cap (for DC isolation). Connect the sleeve
of the plug to the TNC PTT. The plug's tip is unused.
Set the TNC audio for 50 to 80 mv audio output into a 2K ohm
impedancie.
All mods found on this database are offered to me by other amateur radio hams or captured by Packet system.
KB2LJJ take no responsibility or liability for any damage done resulting from any modification.
However, I haven't received too many. If all of you contributed a little more, I believe I would be able to help
all the other ham's that are looking for these mods. I know it is possible to get more mods from all the Ham's because of
the wide range that exist throughout the world. By doing this we can flourish and enjoy more of this hobby that
we've taken part in for so many years. Furthermore, I ask you not to forget to send me any modifications that you might
have through email. I would really appreciate it.
Email webmaster@kb2ljj.com
73's
John Ribeiro
KB2LJJ