By Chip Coker KD4C
As we mentioned earlier in the year, we’ve been hard at work planning some improvements to the K5RWK repeater systems. There are three separate activities in work.
- Improvements to the main Palisades repeater site
- Relocation of the UHF 443.375 Repeater to East Renner
- Replacement of the DMR Repeater at the UTD site
It’s been a challenge to get everything done that we need to do because of general pandemic slowdowns and because if antenna work is required, we are at the mercy of the city and their contractors since we are not allowed to do antenna work on city or city-leased facilities.
Improvements to the main K5RWK repeater site
In general, the main 2M repeater (147.12) and the Fusion repeater are working fine. However, occasionally the 2M repeater has some intermod and desense issues that we believe are caused by either a problem with the feedline (1-5/8″ heliax) or corrosion in the antenna connection. Since we are not allowed to do any antenna or feedline work at the Palisades site, we have been waiting for an opportunity when the city will be performing maintenance on their equipment. When that happens, we will be replacing the feedline and moving the antenna to a better spot on the building (which will make the feedline shorter). We will also be installing a backup antenna in case we have additional problems. We are also changing the fusion repeater antenna to one with higher gain, which will improve the range.
Again, we ask for your patience since we are not at liberty to do the work. Andrew closely monitors the performance and if he detects an issue, he will switch to the backup repeater. This summer has been dry and we haven’t had many problems recently (further reinforcing that it may be a water-related issue), but winter is coming so hopefully we can get this resolved soon.
Relocation of the UHF 443.375 repeater to the East Renner Water Tower
We have a one-time opportunity to relocate the UHF analog repeater to a much higher location. Currently it is located on the old Methodist Hospital at Collins/Campbell and only on a 6 story building that itself is in a hole, so the range isn’t great and because of that the repeater is underused. The city has almost completed the conversion of their traffic signal system from a point-to-point RF to a LTE cellular system. Consequently, the point-to-point equipment is being removed from the city water towers. We intend to take advantage of the climbing crew scheduling that will remove the traffic signal equipment from the East Renner water tower (east of Breckenridge Park at the East edge of the Richardson panhandle) and we will install a new UHF repeater antenna and feedline, as well as new duplexers and repeater – overall a much improved system. We are also installing more AREDN equipment for RACES as well as more weather observation cameras (similar to what we have on the Palisades Building and the just-repainted Holly Water Tower at Richardson High School). And we will also install a 10M receive antenna for the N5UA/W5DFW 10M repeater.
The resultant (and almost all new) UHF analog repeater will have much improved coverage from the 160′ antenna height and will also better cover East Richardson, as well as South Plano, Sachse, Wylie and North Garland – overall an underserved coverage area. We applied for and were awarded an Irving ARC Micro-grant for 2021 (thanks Irving ARC!) which will pay for the new antenna and duplexers – almost $1,700 worth – and we are supplying the repeater, feedline and enclosure. We hope to have this done by the end of the year (again, not under our control since we cannot do the antenna installation).
Replacement of the DMR Repeater at the UTD site
Our 440.375 DMR Repeater, installed at the UTD site, has a failed Power Amplifier. Evidently it’s a relatively common failure of a certain series of XPR8300 repeaters. While it would be possible to send it for repair, there’s no guarantee that it wouldn’t happen again to that same hardware. The best option is to replace it with a newer-model DR-1X and put some additional protection components on the output. Thanks to some horse-trading, Andrew has said replacement repeater in his possession, and we are awaiting an opportunity to get over to UTD and do the swap.
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As you can hopefully see, maintaining repeaters is a time-consuming and sometimes difficult, but it’s one of the benefits of being an RWK member so we want the best systems that we can afford to provide. Thanks again to Andrew KE5GDB for having the knowledge to install and maintain our systems and for taking the time to do it for the klub.