June Engineering Committee Notes & June Work Day

June fared to be a month with some successes and some learning experiences for the SLSRC Engineering Committee.  Let’s chat about some wins for the month.

During our June work day we successfully brought the 665 Skinker (146.970) repeater site online with our 5Ghz network.  We had two crews adjusting the dishes at each site, trying to line them up as we used the 146.940 repeater as a communication method. The 665 Skinker site 5Ghz dish basically shoots down Hwy 40 to MoBAP at 3015 Ballas Rd. where another dish picks up the signal.  This is around a 7.5 mile shot. It then goes through a switch and gets routed back over another wireless link to 9666 Olive Blvd. We have this 2 hop wireless signal because the 665 Skinker site is blocked to 9666 Olive Blvd by a large building in Clayton. Since 5Ghz thrives best on line of site, we could not get the sites to link up from a direct path.  The 665 Skinker site was the last site to be brought on line, rounding out all the sites with remote and internet access. This is a huge goal successfully implemented by the team as it gives the committee the ability for remote command and control of the repeaters via the internet.

Another success we achieved in June was replacing our internet router with a Ubiquity USG 3P router at the 9666 Olive Blvd site.  Our old router was a Linksys 1200, which fared well for the role it was playing, but if you’ve been keeping up with the internet security trends, it was #1 on the list for the VPNFilter virus that has been hitting out-of-date routers.  This new router allows us much more insight on our LAN and WAN traffic by using deep packet inspection and trending data to help us catch problems before they become issues. This new unit will also serve as our VPN server to allow us secure access into the site.

There were a few opportunities for improvement during the month of June for the committee.  We tried to replace the 146.850 repeater with a Fusion repeater with CTCSS on the output. To do this, we needed to purchase an external CTCSS encoder/decoder and wire it in-line with the Fusion to the CAT1000 controller.  When a Fusion repeater is connected to an external controller, all internal controller functions of the Fusion are disabled. Since we wanted to keep the 141.1 input tone and also add the 141.3 tone squelch functionality, this external board was needed.  Once we had it working on the bench, we installed, did some quick testing and turned off the old repeater, and the complaints started to roll in. We heard everything from reception issues, muffled audio, weak output, so we knew there was a problem. We removed the Fusion, put the old repeater back in service and we are working on trying to fix the issue.  

In the process of installing the new repeater, we think the cabling harness that connects the Echolink/IRLP controller board to the CAT1000 shorted out.  Inside the harness there are a few resistors to limit the audio coming out of the server into the controller, and we think those connections might of been compromised.  Right now the Echolink server is being checked out and a whole new cabling harness will be replaced when the Fusion is put back into production. Hopefully, by the end of the year, the committee can replace the current Echolink/IRLP server with a Raspberry Pi to make the hardware more supportable.  Right now the Echolink/IRLP server is running on a very old HP computer that was donated to the club.

While some of the crew was at the 665 Skinker site aligning the 5Ghz dish back to MoBAP, they had the opportunity to take a look at some antenna issues we’ve been having at the site.  We’ve noticed after heavy rain storms, the repeater just doesn’t perform. As the guys disassembled the antenna, our fears were confirmed with water in the antenna. The crew drained the water and tried to seal it up the best they could, but with no silicone, there wasn’t much to be done.  In the near future that site will be replaced with a new Fusion repeater and DB224-E antenna to bring that site up exactly like all the rest of the 2m repeaters the club owns.

As we look back on June, even though we had some setbacks, there was quite a bit of work we  accomplished to move the sites forward.  We will continue to build on this and learn from our mistakes, as it makes for great learning opportunities for the committee.