Repeater

The Yellow Thunder 2 meter repeater is located high atop the Baraboo Bluffs, 5.5 miles SE of Baraboo on the Pointon Communications Tower.

The repeater transmits on 147.3150MHz with a 123.0Hz CTCSS tone and receives on 147.9150MHZ with a 123.0Hz CTCSS tone.

Our receive antenna is located at the 400 foot level (on the top) and the transmit antenna is located at 320 feet.

The repeater system is all commercial grade, industry standard equipment.

The repeater radio is a Kenwood TKR-750. This unit is rated at 25 watts continuous duty. From there we are driving a Crescend Technologies PSV100-15RF amplifier. 15 watts of input power gives us a nice, clean 100 watt output. The system is controlled by an S-COM 7330 repeater control panel.

The transmitter is fed into a Wacom transmit combiner. This allows our repeater to share the antenna at 320 feet with other VHF repeater transmitters.

The receiver gets it's signal from the top antenna at 400 feet. This signal is fed into a Wacom receive combiner, where the signals are pre-selected then amplified and fed into a multi-coupler. From here it goes to our receiver and other VHF repeater receivers.

Here's a photo of the Amplifier, Controller and Repeater Radio


This photo shows the VHF Combining system. The rack to the left of the repeater is for the transmitters and the rack to the right is for the receivers

At the repeater site we have incorporated a battery-backup system in the event of a power failure. This consists of an APC XS-1500 UPS with 2 external 120AH gel-cell batteries. This will give us an approximate run-time of 6 hours minimum with normal use.

When there is a power failure at the site, the repeater controller makes some changes in how the system operates.

First, the repeater hang-time is reduced to 1 second from 5 seconds.

Second, the letter 'B' in CW is appended to the end of the repeater hang-time.

When you are using the repeater during a power failure, when you un-key your mic, you will hear the courtesy tone, a 1 second delay, then the letter 'B'. This is to let everyone know that the repeater is on battery power and to keep your transmissions short (if possible).

During extended power outages, which are very rare, we have a small generator available.