This article explains how to add USB based CAT control to a Kenwood TS-50 and maybe squeeze some extra life out of this great radio when it comes to digital modes.
Kenwood TS-50 USB CAT Control: Gathering Supplies
The bottom of the TS-50 has a small removable plastic disk that allows the user to access a 6 pin connector which the no longer available (and expensive) Kenwood IF-10D computer interface connected to along with the also expensive (and no longer available) Kenwood IF-232C serial converter.
The original Kenwood IF-232C accessory permitted the inverted TTL communications native on the TS-50 to work via standard RS-232 serial communications at a blazing 4800 baud which is more than fine for simple communications between a radio and computer.
While there are some other aftermarket solutions still available in 2020, there is a cheaper way.
For less than $20 in parts, you can add modern CAT control to your TS-50 for easier use of digital communication modes like PSK31, FT-8, FT-4, JS8CALL and so much more.
We will also not need to be removing that little plastic disk, so leave that alone.
To add modern USB CAT control to a Kenwood TS-50 you will need:
CP2104 USB-TTL UART Serial Adapter
JST ZH 1.5MM 6 Pin Female Single Connector with Flat Wires
Some ingenuity to mount the CP2104 in your TS-50
Kenwood TS-50 USB CAT Control: Connections
The below photo diagram illustrates which of the six pins on the Kenwood TS-50 offers what function.
On the CP2104 USB-TTL UART serial adapter, we are going to need to attach the following wires.
For this to work, matching up the TX to the RX and RX to TX pins are needed between both devices.
While some other less detailed guides made it seem that only the TX, RX and GND pins were needed, on the recommended UART serial adapter, we also need to connect the 5V line for a total of 4 wires used. The remaining two wires from the 6 pin pigtail were just left for future use and taped up.
You will see the onboard green LED blink to show that communication is happening between the radio, TTL adapter and computer.
Mounting the CP2104 inside the TS-50
There are not many places to put the TTL adapter inside the Kenwood TS-50 unless you want wires hanging out of the TS-50 which looks messy and unsafe, so now is the time to get organized. If you wish to be neat with this modification, you will need to cut a hole into the side of your TS-50 on the side of the bottom cover.
Using the TS-50 CAT Upgrade
When using software like FLdigi, you can use the “hamlib” for control and select the TS-50 from the menu of supported radios. This is the easier path for CAT control.
Be sure to set your speed to 4800 baud and you select the correct COM port. Most other settings should be automatically found when using FLdigi and most other software.
After you have the software configured, then go ahead and power up your radio after connecting the USB cable to the TS-50 and into the USB micro port.
You should be easily be able to change frequency on the radio and have it track correctly in your software of choice.
Using a TS-50 on digital modes with CAT control
Adding CAT control only offers control of frequency and some other basic functions of your TS-50. This upgrade does not route any transmit or receive audio, nor does it offer PTT control.
It is possible to use the TTL adapter and a simple 4N26 optocoupler with the CTS wire to add on PTT, but its possible to accidently trigger transmit while the radio powers up or down when the USB wire is connected between the radio and computer, so this feature was left out of this article on purpose. If you wish to enable this convenience, that is up to you.
You can follow this article by HB9AMO to add PTT if you wish and by using the extra wires we taped up before from the 6 pin connector.
Routing of audio signals and PTT is done via the 8 pin microphone connector through your interface of choice such as a Rigblaster, Signalink or something like those devices.