TS790 cat interface

A CAT interface  for the old TS790 144/432/1292 tranceiver

to work with N1MM  including the internal CW keyer DTR and "PTT" RTS

and WSJT MSHV with "PTT" control

Using the 3€ FTDI USB serial interface picture bottom page

first i bought the Kenwood USB serial interface cable

that cable has the TS790 special 6 pin DIN plug

this interface works well ...as long as you cut the 4-5  wire bridge on the ACC din..

with the wire bridge it did go offline after 30 seconds or so 

Kenwood interface cable with CH330 eBay 15€ 

  This type Kenwood interface cable uses a tiny 6 pin USB CH330 chip 

The driver is CH340 known for Arduino it workes in W7/10 64 

It has only TX RX Usart function no DTR RTS available

 The TS790 settings are 4800b 8bit data 2 stop  default 

N1MM does not list the TS790 it has the TS890  but that one does not support modes

the TS2000 does support freq and modes and let you switch 2/70/23
it seems the TS2000 Hamlib is the best choice. 

N1MM VHFDX logtype  so hat you can select VHF and UHF bands in general logging mode

That is logging with locator and remarks for general use

it is a pity that the DX general logging mode i always use  does only have the HF bands buttons

but it follows the rig frequency if tuned at 144300 f.i. 

With transverter use it is possible to display the correct frequency by setting the offset frequency 

left mouse button on bandmap index: set tranceiver offset frequency in kHz 1296000  146000 f.i.

picture below is general DX logging not contest mode mixed  that seems a flaw

And for some reason N1MM keeps hanging in FT8 mode and does not switch to  rig mode i have to type USB enter to correct that..

VHFDX type log general logging no contest that is also faulty text...

to continue

I use only the DIN plug of this Kenwood cable

And the  cheap FTDI USB serial interface below that has the complete i/o RTS DTR 

it needs like the CH330 logic inverters to make the TTL logic positive

I drawed with pencil and paper a diagram, i would like a PC schematic program that can do this

but that seems to be very difficult .. the libraries do not have the right parts

I have tried several schematic drawing programs including Fritzing  nice but does not have the parts needed and to make that work for you you have to work for the program to get it right 

it should be the other way around ..

Even a scann of my hand drawing was not correct a PDF can not be used for this page and a jpeg scann does only show a part of the A4 for unknown reason

 I never get what i see it seems random what i print or scann

this is rocket science for me... 

so i took a picture of the drawing with the smartphone mailed it to myself and then paste it here that is the only option to do it.

The ACC1 computer interface connector  has 6 pins
I used the layout from Rigexpert the TS790 doc does not show ACC1 connections.

ACC1 I had to remove wire jumper 4-5 “CTC RTS” to get a long time stable CAT connection

With 4 and 5 connected the CAT communication stopped  after some time 

I wonder if the RigExpert is functioning having pin 4-5 connected.

Could be those signals are used by the original Kenwood serial interface   CTS is  input  and RTS  output to the TS790 CPU.  Nothing found about the function of these signals.

What could be the use of the signing an output to an input  over an external connection?

The external programs do not use hardware handshakes anyway.

So i would free pin 4 and 5 for more useful functions like "PTT" and "CW"

to have 3 pins 4 5 6  free for that

The internally connections must be rewired to get a full functional  ACC1 communication port

that works like the K3 data port