The 145.310 Mhz repeater site is located atop Mt. Thorodin at an elevation at 10,511 feet, approximately 12 miles southwest of Boulder, Colorado. This repeater has reliable coverage from Cheyenne, Wyoming to the north, Monument, Colorado to the south, Limon, Colorado to the east, and the continental divide to the west.

The Mount Thorodin repeater site is the hub of the Connection. The Rocky Mountain Ham Radio IP microwave system traverses the front range from there and we’re connected directly to it.  At this location is the transmitter and a voting receiver on the 145.310 MHz VHF repeater. The repeater is a GE Mastr III commercial unit converted to amateur use. VHF duplexer is a 6 cavity from WACOM. The VHF repeater uses a Sinclair four bay folded dipole antenna.  The linking over IP allow for full-duplex break in operation between all of the east and Front Range repeaters, Breckenridge, Akron and Durango use the commercial internet.

This configuration is not the old “HUB” system as it used to be.  It is now a system linked by private “Allstar” Radio over IP Systems and all of the controller and messages are generated by the linux hub controller at the Thorodin Mountain site.

The links report morse code “L” (dit dah dit dit) on the local repeater to indicate that traffic comes in over a link.   Your local repeater reports always “K” or (dah dit dah)

The North West systems (Craig, Walden, Steamboat and Kremmling) uses UHF links.  We’re frequently asked for the frequencies of the UHF links. We don’t give them out for a reason. If you use the UHF links, portions of the system will only link in one direction, rendering your audio unheard on some repeaters. We discourage the use of our UHF links for this reason.

The photos below are quite old and the equipment has transitioned several times since these photos were taken in the early 90s.  More updates and current photos will be posted as soon as we find out who has them!

As seen below, the Thorodin repeater package is pretty tightly packed! In order to keep our rent to under $150 per month, we had to fit our equipment into a two foot square, no higher than four feet from the floor!

Mt. Thorodin, Colorado

The Flatirons of Boulder, Colorado, with Mt. Thorodin (home of the 145.310 MHz repeater) in the rear.


Our work crew inspecting the antenna location prior to antenna installation.

Connection volunteers getting ready to erect the 145.310 repeater antennas.

Continued preparations for antenna installation at the Mt. Thorodin repeater site.

The work crew just about ready to erect the folded dipole for the VHF repeater.

After installation, our antenna is the highest on the building! (UHF antenna not shown.)

The VHF repeater mounted on top and UHF repeater on bottom. A lot of heat!