Universal Tuner Interface

Project files are available for download here.

Download User Manual

Radio Interface
Tune button on transceiver can be used to start tune or bypass tuner.
Repeated tune in 3sec will start Full tune.
CAT command can be used to start tune or bypass from PC.
Compatible with TS-2000, TS-480, TS-590 or any rig capable of controlling Kenwood AT-300 tuner.

Remote Control Panel (optional)
Using just 2 LED's and a push button to change antenna ports on remotely installed tuner.

Computer Control (optional)
Connect to PC LPT port to switch between antenna ports or bypass tuner.
Ham Radio Deluxe can be configured to automatically change antenna when changing bands.

Automatic Power Amplifier Control
Safely switch OFF the Power Amplifier during tuning, changing antenna port or bypass operations.

Project Status

At this point all functions are working fine. Tested with 50ft S-Video cable extension between interface and AT600ProII and with Ameritron ALS 600 Power Amplifier.

UTI application

Update April,23, 2013
P.C.Boards and parts for the first batch are on stock - ready for assembly.
User manual is ready for download: Kenwood Remote LDG Tuner Interface KTI-LR.

Update April,2, 2013
Prototype was tested and working fine. P.C. Boards and parts have been ordered.

Some History
This was started around Christmas 2011 when I changed my old and trusted MFJ-994 (with Kenwood interface) to LDG AT-600Pro automatic tuner. Don’t ask me why, I liked the idea of adding 6m band and wanted a new toy. There was no Kenwood radio interface available, so I started to build one. I made a prototype and a couple of days later found a bug in the AT-600Pro radio interface. The tuner was not pulling down its Key line when tuning was started from radio interface by pulling Start line as described. The interface (and TS2K) was not able to see that the tuner was activated or when it was finished. I wrote a couple of emails to LDG, and Dwayne told me to wait for the fix. I found a workaround that made it work by pressing AT button on TS2K, then waiting the tuner to finish, and pressing again to stop tuning. It’s not very convenient, but at least I can use it and safely put my PA in standby when tuning. I checked in June 2012 to see if LDG was going to fix the bug, and recently found out about the new AT600ProII with “Meter Interface”. This new serial port gave me the idea to upgrade to AT600ProII and start making the new “universal” one with more features.