Minutes of the Board of Directors Meeting of
The Rib Mountain Repeater Association
11 January 2004
Weston Fire Department Building, Weston Wisconsin
The meeting was called to order circa 19:45 by President KC9NW.
Present were, KB9VBR, KC9NW, and K9DB.
K9PT was absent with the flu, and KC9UC could not attend due to a prior commitment.
The first order of business dealt with a proposal by K9DB regarding the re-establishment of the 146.04/.64 repeater on Rib Mountain. The written proposal as submitted follows:
Proposed Modification to the RMRA Repeater System on Rib Mountain
4 January 2004
Reasons for Proposal:
Of primary concern is interference and subsequent degradation of the performance of the 146.22/.82 system. This interference, primarily 146.22 MHz receiver desense, can be mitigated by some or all of the following actions:
o Maintaining vertical separation of the antennas. The antenna heights as proposed would provide about 160 feet of vertical separation.
o Establishing horizontal shielding. By adjusting the angular position of the mounting brackets, the tower structure and commercial feedlines can be used to shield the two antennas from each other.
o Reducing of power output of the 146.64 transmitter. The WVRA ran about 100 watts into the antenna. Initially, this transmitter could run 10 – 20 watts.
o Employing more sophisticated isolation measures such as circulators, cavity filters, and digital filters could be used as funds become available.
It should be noted that the bracket and feedline are already in place at the 125-foot level, and are owned by the RMRA.
Paul Nelles K9DB
4 Jan 2004
- end of proposal -
After discussion it was decided by consensus that even though the 146.22/.82 system probably does suffer some compromise in antenna pattern to the west, a reconstruction of the 146.04/.64 system on Rib Mountain would not be desirable. With the removal of .64 from Rib Mountain, it is believed that the 146.22 MHz receiver can be reequipped with its preamp and returned to near its maximum performance. K9DB’s proposal had assumed that interference from the .64 system was due entirely to the 146.64 MHz transmitter getting into the 1466.22 MHz receiver. However the problem was a result of a more complicated mix of frequencies including a harmonic of a strong 146.04 MHz transmission. The permanent solution may involve running a split antenna system using antennas at both levels. A single additional receiver on the west side of the tower and multiple remote receive sites remain as plausible solutions.
Tower crews are scheduled for commercial work later this week and may be available to reinstall the cross band coupler removed in October and re-enable the 444.3 MHz UHF system. The noise has not been present since the coupler was removed, and the coupler has been checked out on the workbench, leaving the coupler to antenna jumper as the likely source of the noise. This will be swapped out.
The immediate system engineering goals of the organization were prioritized. They are:
1. Return the existing antenna system, both VHF and UHF, to fully functional.
2. Installation of a second VHF antenna on the RMRA bracket at the 125-foot level.
The long-range system improvement goals as will appear in any capital improvement funds request were prioritized. They are:
1. Replace the existing Spectrum Communications 146.82 MHz transmitter and power amplifier system with a newer or state-of-the-art transmitter package.
2. Replace the obsolete ACC Controller system with a newer or state-of-the-art controller, preferably one that can accommodate multiple repeaters.
3. Improve receiver coverage with multiple remote receiver sites
It was decided that any request for capital improvement funds should have these goals enumerated into this three-tiered plan.
New Wisconsin Section Emergency Coordinator Bill Niemuth KB9ENO has agreed to speak at the February quarterly meeting. However, the WVRA announced at the meeting Tuesday night that they were attempting to bring him in at about the same time. In order to avoid duplicate programs, it was decided that the RMRA should suggest a single jointly sponsored event. K9DB will contact Myron Oestreich KB9STB to coordinate.
Officers for the 2003-2004 fiscal year were chosen by consensus. They are:
President - Rich Maier KC9NW
Vice-President - Dean Andrewjeski K9PT
Secretary - Paul Nelles K9DB
Treasurer - Mike Martens KB9VBR
Member at Large - Bill Bergs KC9UC
Meeting adjourned 21:30.
Paul Nelles K9DB