Author Archive: Jan (KD7ZWV)

Repeater Status – MARC Repeater is OFFLINE

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REPEATER UPDATE

As of Friday, 19 DEC 2024 at 1500 MST, the MARC repeater is BACK ONLINE.

Dan (N7XDL) completed the insulation in the window and has powered the repeater online again.  He also installed some recording thermometers (courtesy of Justin, [KK7VBL]) so we can track the temperature over time.

Many thanks to all those who helped with the new feed line install and especially Dan for his hard work to get the repeater back up.

Future Sunday nets will again be held on the club repeater, starting this Sunday!

PREVIOUS UPDATE

Murray City is still trying to find a suitable contractor to perform the tower work.  Sammie (NA7EGC) has offered the use of one of his repeaters on Ensign Peak for the interim period.  This repeater is at 224.080 MHz, negative 1.6 MHz offset, and tone of 136.5 Hz.  As this is a new repeater, it is not currently included in any standard load files.  If you need help programming this repeater into your radio(s), please bring your radio(s) to a club meeting and someone will help you.  We will be using this repeater for Sunday nets moving forward until our club repeater is back in operation.

PREVIOUS UPDATE

We have been advised that the tower contractor is unable to perform the work this week, so the repeater will NOT be back on line this Thursday as planned.  Please do NOT come to the tower site at 8:00 AM on Thursday 25 JUL 2024 or you will be lonely.

We will advise when we have more information.

PREVIOUS UPDATE

Thursday, 25 JUL 2024, at 8:00 AM any member of MARC who is available is requested to meet at the repeater site to assist with the installation of the new heliax feed line to the antenna.  Murray City and the Murray FD have purchased sufficient foam core heliax cable to go from the shack to the antenna and have contracted an installer to climb the tower, install the new cable, and adjust/tune the antenna in situ.  If you are available to help that day, please come to the tower site at 8:00 AM.  Bring a hard hat if you have one and you'll probably want gloves as well.

Expectations are that the repeater will be back on line later that day!

ORIGINAL MESSAGE FOLLOWS

Until further notice, the MARC repeater (223.960 MHz, standard load channel 27) is OFFLINE.

A few weeks ago, the repeater failed with a "PA FAIL" indicator.  At the time, we were able to bring the repeater back online, but a week later it failed again in the same way.  MARC members pulled the repeater from the rack and had it examined by a local repeater tech, who identified a blown cap in the finals.  The cap was replaced and the repeater is once again functional... HOWEVER:

When reinstalling the repeater, some additional testing on the feedline and antenna configuration took place.  You may recall that when the repeater was initially installed, we had a length of Heliax cable donated to the club, but the cable was not long enough to reach all the way from the antenna to the repeater.  The final 70 feet or so was bridged with LMR-400 cable.  Analysis of the installation showed that the feedline and antenna is presenting an SWR of 1.6:1.  With the repeater pushing 35W of power up the cable, this results in a reflection of about 4W of power back into the repeater's output finals.

While many repeaters would be able to handle this, the Quantar repeater we have appears to be extra sensitive to this type of SWR condition.  We need to replace the coax with a continuous length of Heliax cable and retune the antenna in situ (on the tower).  We have chosen to make plans to do this BEFORE putting the repeater back online.

We have identified a source for the cable we need, but it is quite expensive.  In addition, installation of the new cable will require someone climbing the tower, and Murray City (the owners of the tower) require that this be done by a professional tower crew for insurance purposes.  We have brought the requirements and numbers to our contact with the fire department and the city is currently working on providing the funds required.  Unfortunately, this may need to wait for the next budget year (which starts in June).

For now, we will continue using the 223.440 simplex frequency (standard load channel 29) for our Sunday evening nets, and we are also exploring other options for temporary use.  Stay tuned to this post for more details as they become available.

Winlink Workshop – Advanced Topics – 11 APR 2024

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This week we continued our 2024 advanced topics program with a Winlink workshop.  Last month, we introduced Winlink and got people set up with the software, got Winlink accounts created, and made connections using "Telnet" protocol.  This month our focus was on getting people working with RF!  We had about ten folks show up with computers, radios, and interfaces and got most of them going on VHF, using both the Crossroads club's gateway (K7XRD-10) and West Valley City's gateway (N7WVC-10).

Next month we'll continue the process of getting everyone working on RF, and we'll experiment with P2P and other techniques.  If you're just getting started with Winlink, we'll help you get going from the ground up.  If you've had Winlink for a while but not used it much, we'll show you some things you can do.  If you're having trouble getting Winlink to work with your radio, bring it to the meeting and we'll help you get it running and working.

Programming Your Radio – Getting Started With Amateur Radio Series – Basic Topics – 21 MAR 2024 and 4 APR 2024

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The fourth session of the Getting Started With Amateur Radio series, this session covers programming your radio.  We start with talking about various settings and configuration options, diving into detail on what each of the options are and why you would choose one setting over another.  We continue with a discussion of programming in frequencies (and where to find the frequencies to program in).  Unfortunately, we ran out of time before we got into the demos, so we'll continue this session next time, which will be April 4th, 2024.

We continued with a discussion of programming the radio's VFO (Variable Frequency Oscillator) manually from the front panel and saving that information into a memory, then covered programming via software with the manufacturer's software, CHIRP, and RT Systems.

Here's the video from the second session:

Download the slide deck here:  Programming Your Radio

Or view the slides right now:

03_Programming_Your_Radio

What to Do When Disaster Strikes – General Meeting – 7 MAR 2024

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Dan (N7XDL) relates his experiences surviving a 7.5 and 7.4 earthquake in Chile and talks about what we should do to be ready to help ourselves, our neighbors, and our communities when the "Big One" hits Utah. MARC welcomed the Salt Lake Crossroads club, who joined us for the briefing.

Download the slides here:  What to Do When Disaster Strikes

Or view them right now:

What-to-do-when-disaster-strikes

EchoLink and the MARC Repeater – Advanced Topics – 15 Feb 2024

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Jan (KD7ZWV) introduced the MARC repeater and talked about the need to provide some type of wide area connectivity into the repeater for MARC members (and others).  He covers repeater linking, both RF and Internet based, and moves on to the solution that MARC is exploring, EchoLink.  EchoLink is introduced and we discuss how to get an EchoLink account, including getting your license validated. Finally, EchoLink configuration is covered.  Jeff (KL7KVG) continues with a discussion of the EchoLink for Android application and then talks about the EchoLink node that he has built as a proof of concept for the MARC repeater.  Finally, we observe a demo of the EchoLink software connecting to the MARC repeater using the node Jeff built, which was on display in the meeting room.

Slides are available here:  EchoLink and the MARC Repeater

Or view them immediately:

EchoLink_and_the_MARC_Repeater

Additional notes:

  1. This project is NOT complete... Jeff detailed a few things that we still want to do, including
    1. Registering N7MRY-R as an EchoLink node
    2. Installing the node at a location other than Jeff's dining room table
    3. Not hogging up Jeff's portable computer (dedicating some hardware to the node)
    4. Tweaking and adjusting parameters to improve the functionality of the node
    5. Configuring outbound connectivity from the node (i.e. DTMF control)
    6. and whatever else we think it needs to be a solid addition to MARC's repeater setup
  2. We had some previous classes that covered repeater linking, including IRLP and EchoLink
    1. April 8th, 2021, Radio Linking via Internet IRLP and EchoLink
    2. October 14th, 2021, we had a joint meeting with the Taylorsville club on IRLP and EchoLink presented by Doug (AD7LO).  This meeting was carried on the Taylorsville Zoom and we were unable to record it.  I believe the slides are the same as recently presented to the Taylorsville club and can be found here:  Doug's IRLP and EchoLink Slide Deck
  3. As mentioned during the meeting, our prototype is not online all of the time... Jeff will be facilitating experimentation with it by bringing the node up about an hour before our Sunday net and leaving it up for about an hour afterwards.  If you want to experiment with EchoLink and the MARC repeater, this will be an excellent opportunity for you to try it out.  Get the software installed, get your EchoLink account set up and validated, and be ready to try it out this Sunday beginning around 7:00 PM until about 9:30 PM.

The Farnsworth .62 Repeater – General Meeting with UARC – 8 FEB 2024

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The four of us from MARC who attended the UARC meeting tonight learned a lot about the "Farnsworth" .62 repeater.  Clint (KA7OEI), the repeater manager for UARC, started with a brief history of the .62 machine, including some unique aspects related to its installation at the Fox 13 transmitter site.  He then delved into ways to extend the coverage of a repeater by linking multiple repeaters together.  Of course, the best example of this in Utah is the Intermountain Intertie, a linked repeater system that covers most of the state, with branches into Idaho, Montana, Nevada, and Arizona.  The drawback to such a system is that each repeater needs to be on a different frequency.  This led to a discussion of the .62's setup, with a master repeater on Farnsworth peak and a secondary repeater on Scott's.  These two repeaters operate on the same frequency, using only one frequency pair for extremely wide coverage.

UARC has posted the recording of the meeting on their Youtube channel, and I'll include it here.  If you're curious how this system works, check it out.  At the end of the presentation, there was also some discussion about direction finding and how to deal with abusive use of the amateur frequencies, which was also quite interesting and may be the subject of a future UARC talk.

Advanced Topics for 2024 – 11 Jan 2024

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Last night we met to discuss what we want to do for the Advanced Topics classes in 2024.  As you may (or may not) know, MARC has a so-called "Advanced Topics" class on the second Thursday of each month.  These classes are intended to reflect more advanced and/or esoteric topics.  Historically, I've presented something about amateur radio that I found interesting... a technology or subject that is related to amateur radio and is more involved than just chatting on the repeaters (or even via HF).

For 2024, I want to continue this model, but extend it.  I want to spend several classes on each topic, starting with an introduction and background, but moving to a hands on session where we (the club members) actually DO something with it.  This may include things like configuring equipment, building antennas, etc. and ALSO includes taking that configured equipment, antennas, etc. out and actually USING it.  I want the Advanced Topics classes in 2024 to be more about DOING than just being SHOWN something.

To this end, I suggested three sample topics that I am interested in and that I thought would fit into this model fairly well.  The topics I put forward were Winlink, 10m operations, and AREDN.

I know we've done some classes on Winlink before, and we participated in the multi-club Winlink Workshop last year that was very well attended.  I want to do that one better... starting with an overview and background on Winlink one month, then having a mini-workshop the following month where we actually get our equipment configured and working, and finishing it up with us taking our gear out and actually using it to send messages, process forms, etc.

For 10m, I suggested a similar model, but concentrating on what you need to get on 10m.  That basically includes a radio and an antenna, so one class session could be on actually building (or modifying existing CB) antennas.  This series would culminate with us getting onto 10m and participating in Paul's 10m weekly net.

And for AREDN, the club has a bunch of hardware that was donated by a ham who was moving.  We could spend a session learning about it, another session configuring the hardware, and a final session hauling the gear out into the real world and setting it up to see how we can make it work.  I think we may be able to leverage UVARC's people as they have been using AREDN effectively in Utah County.

After presenting these three topics, I opened it up for discussion from the group about other topics that may be of interest.  We came up with another fifteen (!) possible subjects.  I'm going to do a little research on these, since many of them will require some level of investment in hardware and/or software (antenna parts, while often inexpensive, are not free).  Once I have some idea of what's involved, I'll put together a little survey for people to register their interest.  If you have an idea for another topic that isn't on this list, please let me know and I'll add it.

Without further ado, here is the list of potential topics for MARC Advanced Topics classes for 2024 (and likely beyond):

  1. Winlink
  2. 10m operations
  3. AREDN
  4. Software defined radio (both receive AND transmit, and what to do with the things you receive)
  5. NVIS (Near Vertical Incident Skywave antennas, how they work, building them, using them)
  6. mounting antennas (mobile and fixed base)
  7. SKYWARN/weather monitoring (to include CWOP and building your own weather station, weather telemetry on APRS, etc.)
  8. APRS in depth (using APRS in events, digipeaters, building a digipeater, getting club assets on APRS as objects)
  9. Digital Voice modes (this we broke out into three sub-topics since there is probably enough in each to spend at least a couple of classes on)
    1. D-star
    2. DMR
    3. YSF
  10. radio astronomy
  11. high altitude ballooning (build a balloon and launch it!)
  12. EME (Earth-Moon-Earth, from what do we need to actually do it, to let's actually do it!)
  13. satellite operations (what satellites are working, build a dual-band yagi, make contact with someone via satellite)
  14. digital (data) modes
    1. packet (build our own packet station)
    2. vara HF/vara FM
    3. PSK31
    4. FT8/JS8
  15. time and clocks (how does GPS work, what about atomic clocks, why do we care about accurate time)
  16. amateur radio crossovers with other hobbies (model rocketry, RC aircraft, drones, aviation, etc.)

Again, if there are other topics that interest you, that are not on this list, send them to me and I will add them to the list.  There are so many things we can do with amateur radio... we have only scratched the surface!

Other topics suggested after this list was first posted:

  1. QRP (low power, 5W or less on HF)
  2. Learning Morse Code (I know we're not going to learn the code in a session or two, but we can cover various techniques and tools for learning and maintaining proficiency in code.)