Kendall Amateur Radio Society



KARS is a diverse club.  We like to think of ourselves as a club with repeaters; not a "repeater" club.  We commenced conversion from analog to digital in 2015, sold off the old stuff in 2017 and then over the next five years, completed this system to make KB5TX the premier repeater system in the Texas Hill Country.

Current Status

  • VHF: 146.64 (-)  pl tone of 88.5.  DR-2 at 1970 feet MSL (110 feet AGL) on Tower Road at 29.86N, 98.77W.  Six miles north of Boerne.

  • VHF: 145.19 (-)  pl tone of 88.5.  DR-1 at1600 MSL near Sisterdale, TX at 30N, 98.43W. Fifteen miles north of Boerne.

  • UHF: 444.9 (+) pl tone of  88.5. DR-2 using the upper UHF antenna on Tower Road, with Wires-X.

  • UHF:  444.925 (+) pl tone of 88.5.  DR-2 using the upper UHF antenna at 1610 MSL near Sisterdale, TX at 30N, 98.43W..

The VHF 145.64 repeater at Tower Road provides coverage as far north as Fredericksburg, West to Kerrville and South to Leon Springs and the north side of San Antonio.

The VHF 145.19 repeater is located near Sisterdale and provides coverage South of San Antonio to the Brooks Field area, Southeast past Randolph AFB and East into New Braunfels and Blanco. Northwest past Fredericksburg and Kerrville then to the Southwest to include Bandera.  Tests will continue to the Southwest to determine coverage around Medina Lake and the US Hwy 90 area west of San Antonio.  Ours is possibly the most capable repeater system in the Texas Hill Country and it is open to all to enjoy.

The UHF 444.9 repeater generally stays in digital mode, which means one will need a radio with Yaesu C4FM to access.  It is connected to Wires-X and can connect other Wires-X rooms.  After 5 minutes of inactivity, it automatically switches back to the SADRC room.  The internet at the tower is excellent;  IP traffic sounded as good as the RF traffic.  Thank you, Mark and Bee Creek Communications.

The UHF 444.925 is set up for analog and/or digital.   This machine is located on a private tower, near Sisterdale, TX with the antenna at 1610 MSL (150 feet AGL).  We plan to put this repeater on Wires-X.

We support Yaesu AMS, which supports both "pure" FM and emerging digital standards like C4FM and Wires-X.  We have APRS capability and a mesh network at 2.4 or 5.8 GHz to a remote site with an internet connection. This gives the capability to "call in" via the internet and participate in NETs from a remote location.  The internet connection is courtesy of Bee Creek Communications, Inc.  We got to where we are today by following the repeater plan we developed in 2017.

73, Don KI5AIU.




The Sisterdale Site Story



Marsh, just below the VHF antenna mount at Sisterdale antenna site for the .19 repeater (approx 140').


Saturday May 21st  dark and early  Don KI5AIU, Jerry N5SGM, & Marsh WA5UBO arrived at the Sisterdale site at about 6:45 hopefully to finish the tower work required in one climb.

The final mounting of the VHF antenna along with its top support. Some grounding of cables, pulling the 2nd 7/8" Heliax up the tower for the VHF antenna, connecting jumpers and strapping Heliax to the tower on the way down.

I had hopped to be down from the tower before noon but that didn't happen. Everything always takes longer when you are up on a tower.

Heliax was rolled out first and a ground cable kit was installed for the top end.

I climbed to the top and attached the pull line and  connected the coax jumper to the vhf antenna and waterproofed it before sliding the vertical out to the end of the mount. 

Finished climb to the top and worked on the top support for the vertical.  Ben K5AYR then arrived to be ground crew help. Shortly we were ready to pull the Heliax up and Ben & Don flexed their muscles and hoisted it up the tower.  I think Jerry was flying his drone getting video of the task being performed.  Once the Heliax was secured to the tower, I was going to attach the other end of the new jumper I had made and the tightening barrel came off in my hand!  I think the ground crew heard my response without having to use the radios!!

Needless to say, it's  going to require another tower climb to replace the cables.

I had issues with 2 other connectors after I had made the jumpers up, different issues but this last one was unaceptail.  I knew they were made in China, but what isn't any more.  They are all going in the trash after I contact the seller!  Don checked the SWR on the UHF antenna that we got hooked up last week and the SWR didn't look good so I'm going to get some different connectors and coax and make another new set. See more about Sisterdale in Club Activities.

73,  Marsh - WA5UBO



Tower Road Site



While working the above, Marsh Pronneke with help from Steve, Mark, Ben, Ken and Don, rebuilt the repeater building to make it water tight.  Then the team rebuilt and rewired the interior so could easily add additional capabilities, trouble shoot, and simply document what we have. They added a demarc board where devices could be mounted and signal/power lines easily traced.  This is hinged so that power can be run behind the board, yet the board can be opened up if access is needed to the wall behind it.  The Power Distribution Unit (PDU) is mounted to the bottom of the board, which allows the board to be opened without disturbing the wiring.  And now the interior of the building and the system arrangement looks like this.  See the presentations folder and then Repeater Report 2021 for all the details.














Steve Lazar has the KB5TX APRS Digipeater on the air from the tower road site since 21 May 2020. Currently we are running an ICOM IC-2100 with an output power of 25 watts to a Ringo Ranger antenna at 30 feet up the tower using a  TinyTrak 4.  Look at and search for KB5TX.  Here it is.




The various station locations which were heard directly on the KB5TX Digipeater are shown below on a screen shot from  Over time this will allow us to estimate what our system coverage.  But from what is shown below, one would have to agree that it is pretty good.



  1. Winlink  is now in operation at Tower Road and soon will be at Sisterdale.

  2. Determine the status of the backup generator we inherited at the site and cost to return to service.  Or should we rely on our current backup capability of the UPS and 72 hour battery capability?

Now, how do we use all this neat capability.  Many KARS members are using Yeasu mobile rigs and a power supply as a base station for FM.  Ben, K5AYR uses a Yeasu FTM-100.  Don, KI5AIU uses a FTM-300.  Mark, N5YZB uses an FTM-400. Meanwhile Al, K5NOF uses a FT2DR handheld at 5W from home with a dual band base station antenna with 6/9 db gain.