Things are changing rapidly with the various APRS stations that I operate. Strangely, it seems that posts about my stations are actually popular. I think that people might like to see real-life applications of APRS, and it may give some operators a little inspiration to try these applications on their own.
The biggest change is that I acquired a Microsat WX3in1 Plus 2.0 TNC. I will write a separate post about this device, but suffice to say that I am quite excited about it. While the Mobilinkd TNC has its niche, that niche is not being used with an APRS gateway. For roughly the same price as a Mobilinkd TNC4 ($150 w/o shipping or cable), anyone can get the Microsat shipped from Poland. And the Microsat TNC can do an order of magnitude more than the TNC4 if it's used for a home gateway or remote digipeater purpose. As I said, I'll write more about the Microsat TNC soon.
My current stations
- KD0TLS-1: This was formerly my gateway, but the Mobilinkd TNC stopped connecting to the tablet that ran APRSIS32. It now operates as an -IS-only station, allowing me to maintain objects and bulletins. If you have an old Windows tablet/PC (to run APRSIS32) or an old Android tablet/phone (to run APRSDroid), you will find this is the easiest way to dip your toe into the APRS waters without spending money on a TNC or setting up an RF station.
- KD0TLS-9: This is my mobile station, and it works very well. I have a monoband TYT TC-8000 HT connected to a trunk-mounted 1/4-wave whip, and the HT is connected to a Mobilinkd TNC2. I use APRSDroid on my phone, and connect to the Mobilinkd TNC2 over Bluetooth. The phone provides the "brains" and GPS. All of this is powered by a cigarette lighter jack and a USB port within a stash box between the two front seats. Everything is shut down when my car isn't running, because no power is being sent to those receptacles. The TYT HT runs a nominal 9w, and it has a solid front-end for RX. The TYT TC-8000 is pretty much discontinued, but still can be found on Ebay and AliExpress, along with accessories like a battery eliminator. While it's a poor choice for FM voice operation, it's ideal for APRS. I have no problems getting my packets gated within the metro with this setup, and when I venture outside the metro I simply upgrade the antenna from a 1/4-wave to a gain whip. If you are looking for a messaging-capable RF mobile station, then this is a very good solution.
- KD0TLS-7: I previously wrote about this station last year, though it's fundamentally changed since then. It now consists of a Leixen VV-898 rig connected to a Mobilinkd TNC, and the rig is connected to an exterior 2M antenna. Basically, it's what KD0TLS-1 used to be, however it now connects to my laptop running APRSIS32. Since that laptop is located over the 30 foot limit for Bluetooth range, it's a very unstable gateway. I operate it when I'm home to monitor the loss of the BT link and restore it. When it does work, it's a fairly effective RF station and gateway. I will, however, point out that Bluetooth is slow. This is maybe the biggest reason why the various Mobilinkd solutions are a bad choice for a gateway. APRS deals in microseconds, and a gateway that is slow will find it is consistently beaten to the punch by other gateways using wi-fi or ethernet. If you are located in a rural area, a Mobilinkd-powered gateway will probably be a suitable choice, because there isn't much competition for packets. In either case, this kind of station will function well as a standalone RF station, provided your computer (or tablet/phone) is within Bluetooth range.
- KD0TLS-4: A new station, this uses a monoband Puxing PX-777 HT (5w) connected to the circular-polarized indoor antenna that I normally use for satcom. I wouldn't recommend this antenna for a home station solution. It's far too expensive and has only unity gain (at best). A basic mag-mount whip on a cookie sheet would perform better indoors placed near a window. The HT is connected to the new Microsat WX3in1 Plus 2.0 (really unwieldy name) TNC over ethernet directly to the router. In spite of the low power and less-than-ideal antenna solution, this station has performed far better than its previous incarnation using a Mobilinkd TNC connecting to a laptop over Bluetooth.
Future plans
Now that I've configured and tested the Microsat TNC, I will move it close to the exterior antenna and set up a permanent gateway using the Leixen VV-898 (10w) rig connected to the exterior 2M gain whip antenna. The Microsat WX3in1 Plus 2.0 requires an ethernet connection, but I've already obtained a wi-fi extender device that allows me to connect the Microsat to my home wi-fi. While I expect a reduction in speed using wi-fi compared with the direct ethernet connection, I also expect it will be much faster than the Bluetooth alternative. This will be the new KD0TLS-4 gateway/digi.
This will allow me to set up a highly-reliable, efficient, and self-contained gateway that can run 24/7. I will no longer be reliant on a Windows 10 tablet that needs weekly rebooting. The Microsat TNC has an embedded OS, and it's designed to run continually for years. I will also set up the Microsat TNC to operate as a full digipeater if I lose connection with the -IS. So, if I lose my internet connection in some EmComm situation, I can still keep the Microsat TNC and the rig running on battery power. Neither uses much power, since the radio only transmits for a mere second on APRS. Using the exterior antenna (plus the greater 10w RF output) will allow for an increased capability.
The -IS station (KD0TLS-1) will remain as it is, maintaining objects, bulletins, and QST messages. APRSIS32 is an excellent choice for such a station, making it easy to do all of these tasks, plus allowing an operator to send STATUS text over the -IS. APRSDroid will allow messages and bulletins to be sent, but not objects and STATUS text, and bulletins/announcements will not be repeated at regular intervals. APRSIS32 and the Microsat TNC (with proper tweaking) will allow all of this.
Likewise, KD0TLS-9 (the mobile station) will continue as always. I will continue to tweak the SmartBeacon settings to provide more responsible transmission rates for my commute and errands. The Mobilinkd TNC2 will use my phone as the "client" over APRSDroid.
KD0TLS-7 will become an RF station powered by my spare 10w TYT TC-8000, connected to my circular-polarized indoor antenna, and using a Mobilinkd TNC to connect to my laptop using Bluetooth. It will not operate 24/7, but should be an effective RF station even when All Else Fails.
The Bluetooth module for the Microsat TNC should arrive soon, and this will allow me to operate KD0TLS-4 using APRSDroid or APRSIS32 as a client, making it a full-featured APRS gateway/digi and RF/IS station. But I will be able to connect to the Microsat TNC whenever I please with my phone/tablet/laptop, leaving the device to operate as a gateway/digi independent of such connections.
My situation, and yours
I live in a condo, and I've attached a mag-mount 2M gain whip to the steel cap of my balcony. Certainly, other operators can use a roll-up J-pole or concealed 1/4-wave whip to duplicate my exterior antenna situation. Once you stop thinking as a ham, you will find that a roll-up J-pole hanging from the eaves will support a few Christmas lights, and a whip will fit behind a flag or inside some other decoration. Even those without an HOA to contend with will find that a J-pole hanging from the eaves of their garage, running to a spare HT with a Microsat TNC connected to the -IS over wi-fi will provide a stealthy gateway/digipeater. Fit the whole thing into a Styrofoam cooler for cold/hot weather. You can run the entire station on an old car battery, because cold-cranking amps don't matter in an application like this.
Also, I live midway between two massive digipeaters -- the Medina W0PZT-1 and the Robbinsdale K0YTH-13 -- so operating as a digi isn't very useful in my case. But your situation may very well be different, and you could operate the Microsat TNC connected to a mobile rig and exterior antenna to provide digipeater coverage even without an internet connection. Remember, the mobile rig only draws significant power when transmitting, and only for a second. A 25w rig and the Microsat TNC can be run off of a solar panel with a battery in most cases, particularly if you don't use wi-fi or Bluetooth.
Summary
While the Mobilinkd TNC is a great mobile and portable solution, the Microsat WX3in1 Plus 2.0 is the superior solution for a home/remote gateway or digipeater. At the very least, anyone can set up an -IS-only station using free software.
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