Connecting a CAT to a Kenwood TKR-720 or TKR-820.
Connecting a CAT controller to a Kenwood TKR-720 or TKR-820 Repeater can be accomplished easily by following these steps.
Build a interconnect cable with a DB-25 male connector on one end and a 15 pin Molex connector on the other end. (Note: a pre-built cable can be special ordered from CAT).
Note: Install a 2200 ohm pull-up resistor on the controller board at the COR #1 position. Set dip-switch #1 to the ON position for an active low COR.
Connector is a male Molex catalog #1625-15PRT (.062 inch pin spacing)
Interfacing a CAT-250 to M/A COM Master III
This CAT Note describes the wiring between a (GE) M/A-COM MASTER-III and the CAT-250 Controller. Connection is made between the CAT-250 and the 2/4-wire 600 ohm balance line ports that would normally be used to connect a remote console via D.C. or tone remote control over telephone lines. The MASTER-III Control Shelf Personality was setup as 4-wire D.C. Remote Control. The digital pots were optimized for audio Input/Output levels of -10 dBm at the 4-wire line terminals with full system deviation. Please note that User Output #1 was configured in this example to control the MASTER-III CG Monitor (PL Disable) function from the CAT-250 controller but any of the available User Outputs may be selected.
Install a 680 ohm resistor across RX AUDIO #1 to ground as this is needed to provide a proper termination for the Master-III Line Output. Remove the jumper block from J8 of the CAT-250 to option the input stage for de-emphasized audio as supplied by the Mastr-III. Strap J-104 (2-3) and J-105 (2-3) on the Mastr-III T/R Board.
Control Shelf Options
Morse Code Options
Information courtesy of WA8WG
USB to RS-232 Converter Cables
Computers today do not have a RS-232 port. Since CAT products communicate using RS-232 this presents a problem. The solution is to purchase a USB to RS-232 Converter Cable and install its accompanying software on your computer. When the cable is plugged in, a VIRTUAL COM PORT will be created. All of the CAT editor programs can only be assigned to COM1, through COM4. Sometimes the software will create a COM5 or higher. In this case you must reassign the COM ports number to work with the CAT editors.
CAT products only require three connections to the RS-232 port. They are pins 2, 3 and 5 of the standard 9 pin “D” connector. When connected to a CAT product, pin 7 is connected to pin 8 and pins 1, 4 and 6 are connected to each other. This is a standard connection when these pins are not being used. This does not cause a problem with a standard RS-232 port. However two of the cables tested show excessive jitter and the CAT products were unable to decode the signal properly.
It was determined that when pin 6 was disconnected from pins 1 and 4 the signal from the computer was stable, jitter free and easily decoded by the various CAT products.
In summary make sure the virtual COM port that is created can be found by the CAT software and if you encounter jitter of the RS-232 signal from the USB to Serial Converter cable remove pin 6 from the 9 pin “D” connector.
Computer Automation Technology recommends the EasySink Model ES-U-1001-C100 Premier USB-RS232 Adapter cable. This cable can be purchased from the EasySink USA web store at http://www.easysync-ltd.com/
Computer Automation Technology tested the Digitus Model PL-2303 Adapter cable. This cable can be purchased from the Digi-Key web store at http://www.digikey.com/. The Digi-Key part number is AE1488-ND. This adapter exhibited the jitter problem. It was necessary to remove pin 6 from the 9 pin “D” connector.
The Repeater Death-Ray provides a simple method of connecting a control receiver to your repeater system without having to use port #2 of the CAT controller. When a signal with the proper CTCSS tone is received by the control receiver, relay K1 will activate disconnecting the repeaters receiver from the input of the controller. This will instantly stop the interfering signal on the repeaters input. The control receiver will now temporally become the repeaters receiver. The control operator can enter commands to turn the repeater off without having to fight to over power the interference.
Connecting a CAT to the Motorola Maxtrac
and Radius line of mobile transceivers.
| Connecting a CAT controller to a Motorola Maxtrac and Radius series transceiver radios can be accomplished by following the interconnections below.
Build a cable with a Male DB25 connector on one end of a 5-wire conductor cable (Plugs into the CAT controller). The other end of the cable will be soldered to the accessory connector that plugs into the Motorola radio. Wire the cable as follows:
2) Since the transmit audio input to the Motorola radio is microphone audio, it's advisable to attenuate the TX audio output of the CAT controller. Some CAT controllers have a 100 ohm resistor from the TX audio output to ground that can be inserted with a jumper plug. If your controller does not have the 100 ohm resistor jumper option, solder a 100 ohm resistor between the TX audio output and ground.
3) The Accessory connector (16 pins) carry the following part numbers: