KD0TLS: Duluth area APRS update 6/14/23

  As with the Brainerd update, I'm trying to break this effort up into bite-sized pieces rather than one massive post. 

 Much of the northern MN infrastructure has long relied on a "digipeater-heavy" model: many big digipeaters feeding very few gateways. Though things are starting to change, the situation in Duluth remains a prime example of that model. Several years ago, the gateway in Knife River (KNFRVR) was the anchor for all APRS traffic (though under a different name), including everything from Duluth. A few years ago, KB1YTR-1 appeared in Duluth proper, and the big digipeater in Tamarack went off-air, changing the landscape quite a bit.

 Before we get too deeply in to an analysis, let's look at a map of the current infrastructure for the area:

Current Duluth infrastructure

 As always, you can click on these maps to enlarge them. The map above doesn't include the new N0MR-11 digipeater near Wales, MN (about 18 miles to the north of Knife River), but this station is also beginning to interact with the Duluth infrastructure. Even more exciting, we are already seeing that N0MR-11 has a weak hold on the Bemidji W0RFP-1 TX gateway. This has potential to realize the dream of an RF link between the east and west sides of northern Minnesota. W0RFP-1 is increasingly busy and taking on a critical role as a hub for traffic. But that, perhaps, is a subject for another post. 

N0MR-11 current coverage

 Duluth itself is ringed by three big digipeaters: PROCTOR, DULUTH, and PRKPNT. The names indicate the location (e.g. PRKPNT is in Park Point outside of Duluth proper). This seems more like over-kill and less like redundancy, in my opinion. Further, all three of these digipeaters beacon at an inappropriate rate of less than ten minutes. Still, this trio hauls in packets from the surrounding areas, and connects Duluth to some of the wider infrastructure in the state. 

Current PRKPNT coverage

Current PROCTOR coverage

Current DULUTH coverage

 What makes this arrangement actually work is the KB1YTR-1 RX-only I-Gate. This is an extremely busy gateway, though much of that load has recently been shed to the KE0OPK-13 TX gateway near Cloquet. And more recently, the big KNFRVR digipeater has transformed into a TX gateway/digi. Both of these TX gateways reach Duluth, and provide RF-based messaging. 

 As I've mentioned before over the years, there's a need for a small-scale TX gateway in Duluth (or the immediate suburbs), or in Superior across the border, to handle the large amount of traffic. An inordinate share of this traffic comes from the digipeater ID packets, including big digipeaters in Wisconsin. Some of the noise-makers have gone off-air over the past few years, but it remains an issue. A small 5W TX I-Gate could easily leverage the surrounding digipeaters to provide reliable messaging service within the Duluth metro. 

 With Duluth as a hub, we can now look at the surrounding stations that feed into that hub and provide coverage to the approaches. 

 MHTOWA 

 In keeping with the theme of naming digipeaters with the nearby town, rather than a callsign, MHTOWA is located in Mahtowa. In theory, MHTOWA is the critical RF link connecting Duluth to the rest of the state -- such as Brainerd, Askov, and even the metro. The reality is that MHTOWA is kind of an "alligator" (big mouth, small ears) that transmits much better than it receives. Instead, it provides the service of more local coverage, extending the range of the Cloquet gateway further south. In keeping with that role, it dovetails nicely with the direct coverage of the KE0OPK-13 I-Gate and the Askov AD0MI-1 digipeater. The addition of even a modest TX gateway near Moose Lake would make it considerably more valuable to the network.

MHTOWA current coverage

 KE0OPK-13 

 This relatively modest TX I-Gate is taking on an increasingly important role. It covers the southern approaches to Duluth, handles digipeater traffic from Duluth, Mahtowa, and Solon (in WI), and provides messaging service. While I tend to refer to it as the "Cloquet" gateway, it's really several miles further south-west in Otter Creek. A small-scale digipeater in Cloquet itself would be a significant boost in coverage.

KE0OPK-13 current coverage

KNFRVR 

  The KNFRVR gateway has gone through several incarnations over the years. For a long time, it was an RX-only gateway with no digipeater capability under the KC0MKS callsign. It went off-air for several months and returned as a digipeater-only station with the KNFRVR name. Perhaps in support of recent marathon events, it switched over to operating as a TX gateway/digi last week or so. Currently, it's the dominant force in the area and could take over Duluth's status as a traffic hub in the future. And with the Ely-based micro-network slowly starting to rebuild -- thus far with the COOKMN and K9MLD-11 digipeaters -- it has potential to shape the growth of the Iron Range's infrastructure simply by providing gating capacity.

Current KNFRVR coverage

Summary 

 The region still seems to prefer digipeaters to gateways, for whatever reason. It also seems inclined toward big solutions, rather than easier-to-achieve small solutions. While some of the old North Shore digipeaters have faded away (Silver Bay and Lutsen come to mind), the addition of the new N0MR-11 digi is a promising sign that we may see coverage expanding further inland. Some kind of gateway expansion to the west of Duluth would be welcome, at least to cover the approaches and serve as a basis for future digipeaters. It seems unlikely that the big digipeaters in Tamarack or Aitkin will return. Rather than wait for big towers to open up, the path forward might be better served with more modest digipeaters in cabins or small-scale gateways in resorts. Certainly, clubs could promote the idea of small TX gateways in members' homes. Perhaps it could be a club project to pass around an RPi gateway (with HT as TX) to various members, each operating it for a month or so. 

 Local operators have proven they have the will to build repeater networks, and even WinLink gateways, across the Range. There is a lot of APRS infrastructure that's simply been allowed to fall into disuse, so perhaps the problem is lack of interest in APRS. The Soudan I-Gate (K0VRC-2) has been down for nearly a year, for example. It's a bit unfortunate, because the relative isolation of the Iron Range would be an almost perfect application of APRS for EmComm and dissemination of information.