Homebrew Kenwood PG-4W

The recently aquired Kenwood TH-D7 needed a basic programming for FM LEO satellites I was looking for some computer program to do so. Luckily even for that old kind of radio there is software. It depends on which version of the radio you have. Mine says TH-D7E G2.0” on the back of the radio (behind battery). I found out that this requires MCP-D7G software version 1.10 (there is a version 1.20 which did not work for my radio).

In the box of programming cables I found one with 2.5mm stereo plug and a DB9 connector that was used for ICOM radios like IC-2820 or ID-51. Unfortunately the pinout differs from what is needed for Kenwood radios obviously. As both are simple RS-232 connections the only thing to change was RX and TX lines and it shows that a simple nullmodem adapter (i.e. crossing of RX/TX) made the thing work. So for reference this is the needed pinout for Kenwood TH-D7:

Plug       DB9
Tip    ---  2
Ring   ---  3
Sleeve ---  5
Selfmade Kenwood PG-4W
Selfmade Kenwood PG-4W

If you happen to have the ICOM version of the cable just make a small adapter crossing pins 2 and 3 of the DB9 connector or use a small gender changer adapter with nullmodem crossing as pictured below.

Programming Set for TH-D7
Programming Set for TH-D7
Nullmodem and USB Adapter
Nullmodem and USB Adapter

This interface does not use 5V or 3V3 levels (like FT-232). So if you want to use a USB connection you have to use a USB<->Serial Adapter with level shifters. Also wiring of the hardware handshake lines (i.e. RTS/CTS) not needed.

Please be aware that any modification to your radio may lead to a loss of warranty. Use this information at your own risk. I am not responsible for any damage to your equipment.