Computer Aided Transceiver for Ham Radio

There was a time when transceivers only had buttons to control their functioning. Radio amateurs have given the term Computer Aided Transceiver (CAT) to a very specific device. With that CAT interface, the time has changed. The technological revolution has extended the conventional transceiver with the Computer Aided Transceiver (CAT) interface, which enables to control transceivers through a program running on a computer. Using CAT, controlling the functioning of ham radio transceivers becomes easier and more user friendly.

With the help of logging software, CAT can be used to connect ham radio rigs to a PC for better control over the ham radio frequency. And, the best part is you can use it with any type of ham radio like Yaesu, Kenwood, Baofeng, ICOM, etc. Also, you need to understand that on the market, you will find CAT devices of different brands. All devices, according to their manufacturers, are perfect to be used with different radios, but beside that you have to pick the best one per functioning and price; obviously you may not want to invest too much money for the same type of CAT interface that another company is selling at fewer prices.

You may need a USB to RS232 adapter to connect your PC to a CAT device. USB to RS232 interfaces are only necessary for CAT interfaces that are connected to your PC through RS232. One side of the USB to RS232 interface has a USB port (PC side), and on the other end, it has a serial connector, which is pinned into the CAT device. However, before you can use the USB to RS232 adapter, for most adapters you will need to install its drivers on your PC. The related drivers are provided on a CD or DVD along with the USB to RS232 interface on its purchase or you can download it through the manufacturers website. If you are a lucky one and own an old PC that supports RS232 you don’t even need this USB to RS232 adapter.

One such CAT interface for ham radio is CATbox. Let us explore it.

What is CATbox?

It is a Computer Aided Transceiver interface with a modern design having four individual matrix board cards. These cards are powered by an external supply between 9V and 15V. CATbox is able to contain maximum two of these four cards so that a pair of ham radio rigs can be controlled at the same time. The best thing about this interface is it lets the constructor prepare cards out of the CATbox. And, once the cards are ready, they can be easily slid into the box while connected with an external power supply.
There is also a MAX233 chip that is basically a line driver (also called a receiver). It converts the rig’s TTL computer interface voltage to RS232 connection on your computer. It means, without MAX233 and RS232 interface, CATbox may not be of any use. You will need particular software to work these interface. You can find software for these interfaces easily on Google.

Let us go through the technical details of CATbox

Details of the Cards used in CATbox

It has four cards, namely ICOM & TEN-TEC HF rigs; YAESU HF rigs; ICOM & TEN-TEC HF rigs & YAESU VX-7R VHF/UHF Handheld; KENWOOD HF rigs. You can use different combinations of these cards for different rigs to build the desired configuration to fulfil your requirements. For example,

• 1 ICOM & TEN- TEC HF rigs card can be used to connect three rigs at the same time from the same make
• 1 ICOM & TEN-TEC HF rigs & YAESU VX-7R VHF/UHF Handheld card can have two HF rigs of the same manufacturer. With the correct software you can also reprogram the memories and band coverage of the handheld with this card.

Why these cards are used in CATbox?

These different cards are provided to construct the desired CAT interface to work with different rigs fulfilling your specific requirements. While different cards are provided to be used with the CATbox, one thing is common among all of these cards. These cards are made up of matrix board due to a specific reason.
Matrix board is used to ease the task of a constructor. It has detailed circuit diagrams, board layout, and other details using which a constructor can easily build a CAT interface, which is ready to be used with a PC.

For more information on CAT interfaces see the homepage of KC8UNJ or the copy of G4TIC excellent article about his CATbox in our library.