All four of our club repeater systems use Yaesu, Vertex, VXR-5иии Industrial repeaters.

There are five of these repeaters, two for the 2 meter, 44и mhz, dual band repeater, one for the 6 meter AM repeater, and one for each our Multi-Band, Remote Base Repeaters.

All of these repeaters have factory repeater controllers, but they do not have identifiers. Also, most of our repeater systems require remote control of some sort, so the repeaters needed amateur radio controllers that would ID, and have touch-tone switching capabilities.

All three of our repeater systems use different types of controllers for the different features required. The most complex was the Multi-Band, Remote Base repeater.

Well, the Vertex repeater controller was not replaced, only switched off of repeat mode, and the new controllers were installed.

MODIFICATION ONE

Vertex designed their controller cards with capabilities for simplex base remote control over telephone lines, as well as for repeater use.

What I have done is modify these controllers so that the line audio compressors and filters are inline to the repeater audio in and out to the amateur radio controller. Doing this has improved the repeater audio quality and gain levels considerably.

There are two changes to the card. The first one is to install jumpers were to route in-bound controller audio to the phone line input, and to route phone line output to the repeater modulator input.
These 2 jumpers are shown in the picture.

On the flip side of the controller card, you can see where I have removed the audio coupling capacitor C-2и79 from the board.
This capacitor connected repeater receive audio to the telephone line output amplifier, and is the final modification to the Vertex controller.

MODIFICATION TWO

All of our repeater equipment is mounted in 19 inch rack panel cabinets. Vertex gets around $350 for a rack panel kit for the VXR-5иии, and with it there is no way to help cool the repeater.

I purchased some blank aluminum rack panels, and modified them to mount on the front of the repeater, and contain a cooling fan to cool the repeater heat sink. Yaesu says the repeater is capable of 1ии percent duty cycle without over heating, but our equipment shed can get quite warm in the summer, so I felt the fan modification was needed.

Blank repeater panels ready to be installed on the repeaters. The repeaters had to be disassembled to drill the mounting holes. Some of the yaesu screws were used, I had to make 4 additional holes, plus one for the fan wire.

If you are wondering about the large panel, it was intended to rack mount a old tube type 6 meter transmitter to be used for the 6 meter AM repeater. That idea was discarded, and the solid state Ranger radios were used instead.

Aluminum tape was used to cover the side of the heat sink to duct the air through the fins. This works quite well.

MODIFICATION THREE

A switching transistor was needed to turn the fan on. I installed a terminal strip on the ground lug of the power supply. I installed the switching transistor, bias and feed resistors on the strip. The transistor is switched on by the repeater TX light signal, available on the accessory connector.

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MODIFICATION FOUR

The VXR-5иии is a well built repeater, but it does have one major fault. They used a cheap plastic fuse holder for the main DC supply as seen above. The holder gets hot, loosens up and gets hotter, then melts down.

I replaced the holder with a better built, 2 fuse holder. I tied the fuses together, and used 2, 15 amp fuses. I have not had a failure since.

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