Some thoughts as a Minnesotan, American, and Human

January 26, 2026

I generally avoid overt politics on my website and YouTube channel. But I feel that the current situation in the United States has gone beyond politics. I’m aware that many won’t like what I have to say, and may stop reading right here. They might unfollow or unsubscribe. They might try to cancel or otherwise harass me. I might lose income or face other repercussions for speaking out. But I know that I have something of a platform and a following, and I feel that I need to use it for something more important than entertainment or income. Something that’s too important to stay quiet about. Something that’s important enough to risk the negativity of certain people and groups.

I am saddened and disgusted by what America has become. I had hoped we were growing as a nation and a culture over the last few decades. I saw a lot of social progress, especially from young people, and we seemed to be moving towards a kinder, more accepting culture. Sadly, and tragically, there are still backwards-looking people clinging to obsolete ideas like hatred and racism. Those people have gained control of the Federal government, and are trying as hard as possible to erase the progress and freedoms that Americans have been working towards. Trump and ICE are trying to drag America back to the 1950s, or maybe the 1850s. They’re too incompetent to solve the country’s real problems, so they’re scapegoating and distracting and hurting people instead. They’re treating the Bill of Rights like a checklist, seeing how many amendments they can break or ignore. The things you hear about from distant 3rd-world dictatorships are becoming standard operating procedure in American politics. Ethnic cleansing, killing protesters, blatant corruption, private armies, justice for certain groups over others, laws that don’t apply to the rich and famous. Those are no longer things that happen “somewhere else”, they’re standard operating procedure right here. Most of my friends know all this already. I imagine some people will have stopped reading by now, and anyone who can’t form their own opinion will be copy-pasting something about socialist paid protesters into the comments. But I still feel that I need to say something.

Yes, the US has problems. Cost of living, quality of life, housing, jobs, medical care, education, and so many other things. But all you need to do is look around and see who’s trying to fix those problems, who’s profiting from the problems, and who’s trying to blame them on others. If your personal situation is bad, is the minimum wage immigrant or the billionaire CEO the one benefitting from that? Are the people calling for better services or the ones cutting those services really looking out for others? Is some possible welfare fraud the issue, or is blatant fraud and corruption at the top the issue? Is the CEO whose parents paid for everything the bootstrappy one, or is it the person who fled their home country to start over?

We’ve made our own problems through decades of catering to the rich and powerful. The American Dream has always benefitted banks, insurance companies, and investors instead of real people. Those responsible have always tried to blame the problems on immigrants, minorities, socialists, the poor, whoever is a convenient distraction. Other countries have figured out how to provide their citizens with better healthcare, better education, and better job opportunities than us, while also welcoming immigrants and refugees. It’s possible to do both, the US is not a poor country. Even with the problems I mentioned, we’re still wealthier and better off than a lot of the world. Is it really that bad to share some of it? I’m a small business owner and I still vote for higher taxes because I like government services. I like healthcare that doesn’t bankrupt people. I like social safety nets to keep people off the street. I don’t have kids and I still vote for school tax increases, because I’d like other people’s kids to be smarter. I am not a “highly paid agitator”. I would rather spend my money in the hopes that it improves something. And it shouldn’t be about money, or how nice your house is, or how many boats and RVs you have, or whatever the mortgage company wants you to believe. It’s about what’s right for everyone, citizens or not.

To Republicans still bothering to read this, and who still don’t believe some of this, LOOK around. Don’t just look at Fox, or Facebook, or X. Look at international news. Look at a variety of news sources. Look at a variety of social media. TALK to actual people from outside your demographic, or outside the country (and not just the Russian trolls on X). I tend to get a lot of my news from the BBC since they’re outside the US and in the center of most media fairness charts. But I also look at PBS and Fox and I notice how things are spun and which things look like good old-fashioned reporting. My most important takeaways from journalism classes were integrity and honesty. Some news outlets still believe in that, others discovered it’s more profitable to go a different route. It’s not too hard to figure out which ones are in it for profits vs truth.

I’ve tried to be respectful and open-minded about other people’s political choices. The first time Trump got elected, people didn’t *know* how bad he was. I’ll admit I laughed it off the first time. I figured he’d just be an amusing clown for a while and then some adults in Congress or the courts would step in. After a while he wasn’t so amusing, and it turned out there weren’t many adults in the room. The second time, everyone knew he was a multiply-impeached convicted felon and sex offender. But people still voted for him and all the adults left. I tried to be charitable and not just assume every Trump voter is a white supremacist. Maybe some really thought he’d improve the economy, even with his history of mismanaging businesses. Maybe some thought he would protect gun rights, even though he banned bump stocks in his first term. Maybe they thought he’d uphold their favorite religion, even when the actual Pope criticized him. Maybe they truly believed that minimum wage immigrants were somehow more responsible than billionaires for holding them back in life. Maybe they were really invested in what high school athletes had in their pants. Or maybe they were just cool with Trump fumbling everything else as long as he got the racism part right.

And here we are in Trump 2.0. Where he’s not only destroying the country within and without, but systematically betraying everyone who supported him. Trump supporters waiting for the Epstein files got a rugpull. Farmers got international crop boycotts and funding cuts to weather and research. Families struggling with grocery costs got tariffs. Rural residents lost their hospitals and clinics. Open carry advocates got to watch one of them executed in the street. He’s crippled every agency in the name of anti-woke, which really means firing anyone competent. Republicans were so eager to show that “government doesn’t’ work”, they had to make it true by ruining the government themselves. Federal law enforcement has become fractured and ineffective. Actual terrorists and criminals probably love that the Feds are busy fumbling sandwich-related prosecutions. It would be a great joke if he wasn’t doing the same with important departments like health and education. ICE can’t figure out when a suspect they’re after is already in jail. They can’t find their way from downtown Minneapolis to the federal building without asking detainees for directions. They can just about handle arresting a 5-year-old, or a grandpa in his underwear. They can manage to surround a car and shoot an unarmed woman. They can manage to shoot a nurse if 7 agents are holding him down. It would be a great joke if real people weren’t being hurt.

America is not only losing our own values and culture, we’ve become an international laughingstock around the world. We’ve alienated NATO and weakened alliances that took decades to build. We’ve broken international laws and norms that took decades to develop, eroding America’s reputation and credibility around the world. We’re losing rank everywhere from disease-free status to international traveler safety. We’re losing relevance and influence on all fronts. China probably loves it, they’re already beating us in most scientific and industrial fields, and now smaller countries are turning to them as the more stable and reliable partner. Russia definitely loves it, Trump can’t even stay on-message about Ukraine for more than a few days.

Sadly, the checks and balances we were taught in school don’t seem to exist in real life. Congress is mostly geriatric career politicians whose only skill is collecting donor money. Lower courts are completely ignored, and the Supreme Court does what Trump wants as long as the vacations keep coming. Republican lawmakers are content to follow the cult of personality, even when it means giving up their own power. Many Democrat lawmakers have also been remarkably quiet. I can only imagine that a lot of politicians, on both sides, actually love what Trump is doing. He’s made corruption mainstream with free jets and crypto scams. He’s created and shrugged off every scandal in the book from sex to money to treason. He’s escaped all consequences for his actions. He’s done everything a career politician could ever dream of. The Democrats currently sitting on their hands are probably thrilled to try the same things when (if) it’s their turn in power.

Why anyone would support Trump, or ICE, or any Republican politician at this point, I can only assume. And at this point I can only assume the worst. We’ve all had plenty of chances to see what’s going on if we’re actually willing to look. To the people cheering Trump and ICE on, if you’re still reading, please go ahead and unsubscribe. But maybe also think carefully about the examples and standards being set for future administrations that you may not agree with.

To the people still fighting to make the world a better place, thank you. Don’t give up, keep pushing for progress and demanding positive change and growth. Fight for a real future free from mistakes of the past. Fight for the future that everyone deserves.


I bought a satellite!

December 4, 2025

Technically it’s a cubesat “simulator”, but it’s the first really affordable one I’ve seen! Only $130 for the base model (I also bought a radio add-on, and I think they sent me some extra parts).

You can find these at https://www.mysatkit.com/


My Secretcon presentation is online.

November 26, 2025

Here’s my quick overview video of Secretcon 2025:

And you can find the full video of my talk here:


Secretcon Presentation Materials

June 20, 2025

Recently I attended (and spoke at) Secretcon 3 in Minneapolis! My slides are below for anyone interested.

My list of satellite links and resources can be found here: https://saveitforparts.wordpress.com/2024/11/12/resources-for-satellite-experimenters-hackers/


Laser-Cut HRPT Antenna for L-Band Satellites

March 19, 2025

This was an L-Band (~1.7GHz) feed I made for weather satellites like NOAA, Meteor, and MetOp. I’ve previously used some 3D-printed designs like DerekSGC’s (https://www.thingiverse.com/thing:4980180) and T0nito’s (https://www.thingiverse.com/thing:6436342), but my 3D printers often struggle with these.

Since I also have a laser cutter, I decided to try making one out of wood. It’s pretty simple, but works decently well! This one is a left-hand version, but could probably be a right-hand spiral by swapping two of the uprights. In addition to the wood pieces, it needs some kind of ground plane (I used an aluminum pan lid), some stiff wire (I pre-coiled around a 1/5″ PVC pipe), an SMA connector, and an LNA (I like the Nooelec SAWBird+GOES for L-band: https://amzn.to/41CO8sG).

(You also need a satellite dish, but hopefully you already have that if you’re looking for helical feeds!).

You can find the files here: https://www.thingiverse.com/thing:6963608

Or just use the images below. These are sized for 3mm wood, and scaled to 10px/mm. The engrave file can be burned as a raster with engrave power to mark which pieces go where, and the cut file used as a vector / centerline at cutting power.

Below is a preview image of what the full cut and engrave should look like (don’t use this file with the laser).

Mine came out a little loose, I tacked it together with hot glue and then more permanent glue. If you use thicker or thinner material you might have to edit the image to re-size some holes and/or tabs.

I have a video of the project here: https://youtu.be/GUHieqIKgMM


Cyberex CN-7500 Folding Satellite Dish Manual & Walkaround

December 27, 2024

People keep asking how my folding satellite dish is designed, so here’s a quick tour of it:

And here’s a scan of the user’s manual:

As far as where to find one of these, you’re on your own! Another local radio amateur gave me this one, and I’ve never seen them on the used market. Apparently a company called Sub-Lunar makes modern versions, which you can find at https://sub-lunar.com/products. Sadly they don’t list any prices, and if you have to ask…


Resources for Satellite Experimenters & Hackers

November 12, 2024
Fig 1: Some of my satellite dish collection

I discuss a variety of satellite and radio projects on my YouTube channel. Satellite tech has become the most popular topic on my channel, even though it’s not what I initially started with! I often get questions from viewers along the lines of “how do I get started in this hobby?”. Personally, I bought the cheapest possible Software-Defined Radio (SDR) and just started messing with it! I’ve since moved on to slightly better SDRs, but there’s a lot you can do with just a $15-$20 unit from eBay and some creativity.

I usually try to include links and details in the descriptions of my videos, but I don’t always make “how-to” or instructional videos. Usually when I film a project, I’m learning right as I’m doing the project, and viewers are seeing me develop a skill as I do it. This isn’t the most efficient way to teach something, as I make plenty of mistakes along the way! My personal learning style involves a LOT of trial-and-error. My projects also involve a significant amount of dumpster-dived material and equipment, so it can be hard to make a “parts list” for someone to replicate what I did!

Fig 2: A portable / RV satellite dish re-purposed for different frequencies.

If you are just starting out with the amateur satellite hobby, there are a couple directions you can go. If you’re an amateur (ham) radio operator or just into listening to radio traffic, you can get into amateur repeater satellites pretty easily. The International Space Station is the most powerful and easiest to start with. Some info about that is in the list below.

If you want to start tracking and decoding weather satellites, the low-Earth-orbit Meteor series is probably the easiest to start with. Previously some of the US NOAA satellites used VHF, but the ones with this capability have been retired, so some of the info about them is outdated. As of early 2026, Meteor M2-3 and M2-4 can be received on VHF frequencies with a Software-Defined Radio. Images can be decoded with simple software like SatDump. Once you’re experienced with VHF you can upgrade to the L-band signal available from the same satellites (and some others), although this takes a little more effort and equipment.

If you want to try geostationary satellites, the GOES series (in the Western hemisphere) is a great place to start. However, you will need to find or make a satellite dish slightly larger than what’s normally found on houses today. More info and links are below.

The list below is my attempt to compile helpful resources and links related to satellite experimenting, “hacking”, or other hobby-level activities. Some of these are things I’ve written or filmed, and some are links that have helped me learn.

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“How-To” style videos that I’ve made:

Basics of VHF weather satellites (NOTE! The NOAA series is now retired): https://www.youtube.com/watch?v=icADyjm3PBE

Basics of L-band weather satellites (the next step in difficulty, but still not too hard): https://www.youtube.com/watch?v=w5DyJHMw7aY

How to hack Winegard brand portable satellite dishes: https://www.youtube.com/watch?v=6kQa6nfUkIs

How to listen to the International Space Station’s amateur radio repeater: https://www.youtube.com/watch?v=4TRrqPqxpe8

How to find free satellite dishes: https://www.youtube.com/watch?v=_qX30ayOcDU
TLDW: Craigslist, Facebook Marketplace, and estate sales/auctions are great places to try! You can also contact local TV stations and ask if they have old ones. Or you can post on a classified site offering to remove old unwanted dishes from someone’s yard.

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Other articles or software I’ve written:

A how-to article I wrote about turning small satellite antennas into radio telescopes / microwave imagers: https://saveitforparts.wordpress.com/2024/03/19/my-mini-radiotelescope-made-it-into-the-amsat-journal/

My Winegard microwave radio telescope program: https://github.com/saveitforparts/Carryout-Radio-Telescope/

My Dish Tailgater microwave imager program: https://github.com/saveitforparts/Tailgater-Microwave-Imaging

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Links that have helped me:

Satellite tracking and prediction info, probably the #1 site that I use on a regular basis! https://www.n2yo.com/

A great site for visualizing orbits: https://sky.rogue.space/

Starter guide to VHF weather satellites (NOTE! The NOAA series that used VHF are now retired): https://noaa-apt.mbernardi.com.ar/guide.html

More technical info on the APT format used by some weather satellites: https://open-weather.community/open-weather-apt-guide/

Info on receiving Russian “Meteor” satellites (currently the easiest place to start): https://blog.chaospixel.com/linux/2019/12/receive-meteor-satellite-images-with-rtlsdr-gqrx-linux.html

Good basic intro to receiving US weather satellites (NOAA VHF series are retired, but GOES is still available): https://hamsignal.com/blog/this-is-major-tom-to-ground-control

Step-by-step guide to geostationary weather satellites like GOES and GK-2A: https://www.rtl-sdr.com/rtl-sdr-com-goes-16-17-and-gk-2a-weather-satellite-reception-comprehensive-tutorial/

USRadioGuy has some great stuff! His whole site usradioguy.com is super useful. This is his page on Geostationary satellites: https://usradioguy.com/goes-satellite-imagery-reception/

USRadioGuy’s page on low-earth-orbit weather satellites: https://usradioguy.com/noaa-apt-reception/

SGCDerek’s guide to HRPT satellite signals: https://sgcderek.github.io/blog/beginner-hrpt-guide.html

Various satellite frequencies and info: https://uhf-satcom.com/satellite-reception/uhf

More satellite frequencies: https://www.satdump.org/Satellite-List/

Even more satellite frequencies: https://sgcderek.github.io/satfreq/

Using a Raspberry Pi computer for automated (low-earth-orbit) weather satellite downloads: https://www.instructables.com/Raspberry-Pi-NOAA-Weather-Satellite-Receiver/

How to make a DIY motorized satellite tracker (rotor): https://www.sarcnet.org/rotator-mk1.html

International Space Station radio repeater info: https://www.ariss.org/current-status-of-iss-stations.html

CHIRP software for Baofeng and similar radios: https://chirp.danplanet.com/projects/chirp/wiki/Home

Improved squelch settings for Baofeng radios: https://www.miklor.com/COM/UV_Squelch.php

Commercial / TV Satellite info: https://www.lyngsat.com/
Another TV satellite resource: https://www.satbeams.com/

This is a great site for aiming dishes at geostationary satellites: https://www.dishpointer.com/

S-band satellite info (more challenging, and something I’m still learning!): https://www.a-centauri.com/articoli/the-definitive-s-band-satellite-guide

An open source Cubesat project that invites people to set up their own receiver stations: https://wiki.satnogs.org/Main_Page

How to make a simple Yagi antenna for ham radio satellites: https://www.instructables.com/The-Tape-Measure-Antenna/

How to modify GPS antennas for L-band use: https://wiki.muc.ccc.de/iridium:antennas

Making a “cantenna” for GOES: https://lucasteske.dev/2016/10/goes-satellite-hunt-part-1-antenna-system/

3D-printable helical antenna feeds: https://www.thingiverse.com/thing:4980180

Homemade QFH antenna for NOAA and Meteor satellites: https://usradioguy.com/wp-content/uploads/2020/05/20200307-How-To-Build-A-QFH.pdf

Good source of SDR project ideas: https://www.rtl-sdr.com/

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Products and devices I’ve used:
(These affiliate links give me a little kickback from Amazon if you buy from them)

RTL-SDR that I’ve used for many projects: https://amzn.to/3BK54nU

Nooelec VHF filter / amplifier for weather satellites: https://amzn.to/4haNp96

Nooelec L-band Low-Noise Amplifier and Filter: https://amzn.to/4dP8Auf

Combination dish and radio setup for GOES and L-band satellites: https://amzn.to/3YdsiKD
(I have not personally used this entire combo, but I’ve heard good things about it).

Higher-end HackRF One SDR with more features: https://amzn.to/3BL0Zj3

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Useful (and mostly free!) software:

SatDump is probably the single most useful program for decoding almost any satellite signal you’ll come across: https://www.satdump.org/download/

SDR++ is a powerful interface for Software-Defined Radios: https://www.sdrpp.org/

I used to prefer GQRX, and still use it on some computers, as it’s a simpler SDR interface: https://www.gqrx.dk/

MMSSTV for decoding Slow-Scan Television images: https://hamsoft.ca/pages/mmsstv.php

GOEStools for Geostationary Operating Environment Satellites: https://github.com/pietern/goestools

Raspberry-NOAA is a great program for setting up a dedicated NOAA / Meteor downloading station using a Raspberry Pi computer: https://github.com/jekhokie/raspberry-noaa-v2

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Other places to learn:

Reddit has some decent forums for beginners:
https://www.reddit.com/r/amateursatellites/

https://www.reddit.com/r/RTLSDR/

There’s a group chat for the SatDump software: https://matrix.to/#/#satdump:altillimity.com

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Some other videos I’ve made on specific satellite projects (not as much how-to, more of me just messing around):

An automated satellite tracker made from an old security camera pan/tilt mount: https://www.youtube.com/watch?v=8Gz17Mv7RU0

Pirate radio on UHF military satellites: https://www.youtube.com/watch?v=HT2i7mFpFxM

GOES weather satellites:
With a modified TV dish: https://www.youtube.com/watch?v=EK8mFrxxSbY
With a slightly larger TV dish: https://www.youtube.com/watch?v=cb8taCjVigA

SSTV / Cubesat: https://www.youtube.com/watch?v=WRl7ewRimIM

Using an umbrella as a satellite dish: https://www.youtube.com/watch?v=zM84sSXFL0Y

Detecting Starlink beacons: https://www.youtube.com/watch?v=5cwEkhFdXGw

Raspberry-NOAA and QFH antenna setup for VHF weather satellites: https://www.youtube.com/watch?v=WM99A1uUprQ

Hacking a Winegard Trav’ler RV dish: https://www.youtube.com/watch?v=sn-Ayr4j6Ac

Microwave imaging with a hacked TV dish: https://www.youtube.com/watch?v=lVOTZxNCgTM

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Hopefully this has been somewhat useful! You can always email me (gabe@saveitforparts.com) although I don’t always reply in a timely manner!


A Luggable Cyberdeck for Satellites & Conventions

June 24, 2024

There’s something about the 1980s “Luggable” computer form factor that just gets me. Maybe its because I always wanted one in the ’80s, or the retro-future look, or just the convenience of having all your ports and interfaces conveniently on the front. Whatever it is, I’ve been sketching out designs for a DIY version for a while now.

This version uses a Pelican 1340 case, slightly modified to remove some internal lumps and protrusions. The brain is a Raspberry Pi 4 with 7″ screen. I laser-cut a custom front panel and 3D-printed the “Drive Bays” (files available here: https://www.thingiverse.com/thing:6672979)

The larger top “drive bay” holds an accessory set (adapters, SDR, etc) store in a small tackle box. The bottom bay holds a Voltaic V88 battery pack. I picked up a few of these at a local surplus auction and I really like them. They are small enough to be legal in carry-on luggage, but powerful enough to keep the Raspberry Pi running for 4+ hours. They can output a variety of voltages through the barrel plug, can be charged with various input voltages, and can also output USB QC and USB C. They’re all-around a great external battery for your laptop or projects like this.

The Cyberdeck is great for running my satellite antennas and other SDR projects. Despite not having much cooling and being a black case, it seems to run just fine outside in the sun. And yes, I have an old bathtub in my yard next to the satellite hacking deck. I guess I’m a space redneck or something.

Almost immediately after building this deck, I found a real live Osborne 1 luggable at another auction. That will appear in a future video as soon as I re-cap the power supply.

This cyberdeck is great not only for my satellite experiments on the go, it was also a fantastic part of my exhibit booth at Open Sauce 2024, a Youtube/maker/science convention in San Francisco. I used the deck to run one of my hacked satellite antennas for microwave imaging. It was a real attention-grabber at the booth and I think more people may have stopped to look at the deck vs the dish!

The build video for this cyberdeck can be found below:

You can also find my earlier (and less refined) cyberdeck project here: https://saveitforparts.wordpress.com/2023/02/08/the-saveitforparts-spacedeck-v1-a-cyberdeck-for-space/


My mini radiotelescope made it into the AMSAT Journal!

March 19, 2024

A few weeks ago I was invited to write an article for the AMSAT Journal, an online magazine of amateur satellite communications. The article is now out, in the January/February issue! You can see my article below, or you can subscribe to the journal to read all the articles in this issue and back issues! It’s a fascinating magazine, and I just subscribed myself!


A Cheap DIY Satellite Tracking Mount

March 10, 2024

I’ve wanted an azimuth/elevation mount for a while, but never had the money for a real one! Even used models go for $700 and up, so the sticker shock always kept me away. Building my own always seemed complicated and confusing, since it combined all the skills I’m only sort of OK at. Aligning motors, balancing things, programming motion, reading a sensor, and automating the whole rig just seemed like a lot of work!

Fortunately, a few factors made this project relatively easy! First, I got a used pan/tilt camera mount from Ax-Man Surplus. This is a nice robust unit designed to move old-fashioned heavy security cameras, so it can take some weight and doesn’t need too much balancing.

Next, I discovered I could modify the design and code from the SARCNET Mk1 Tracker to use this camera mount. The original project had options for different motors, including a homemade mount assembly and a pair of regular old TV antenna rotors. My camera mount was functionally and electrically similar enough to a pair of rotors that it worked just fine! The main modification I did to the mount was to remove the side cover and slide the vertical limit switches farther apart. This lets me move the mount a full 180 degrees. So far the tracking software hasn’t needed to go a full 180, for overhead passes it just spins the dish and then goes back down the other side. If your camera mount can do a 90-degree elevation, that should be sufficient.

The SARCNET project is aimed at Yagi-Uda antennas for 2m and 70cm (VHF/UHF). This is a typical setup for contact hamsats and talking through the amateur radio repeater on the International Space Station. I wanted to use a parabolic dish for L-band (~1700Mhz). That would let me receive images from satellites like the NOAA POES series, Russian METEOR series, European METOP satellites, etc. While some of these satellites also transmit images on VHF, the L-band signals are higher bandwidth, higher-quality images and contain more data. The VHF signals can be received with a stationary antenna like my QFH rig, but L-band usually requires an aimed directional antenna that tracks the satellite as it passes overhead.

My take on the SARCNET Rotator worked great with a dish! I’ve used this dish for other projects in the past, it was originally a 5.8ghz wireless network antenna, given to me by another local ham. This project would also work with a Wifi grid dish or any small lightweight antenna (even an umbrella covered in foil!). Note that this is a pretty beefy pan/tilt mount, mine is a model PT570. It can handle my reflector without any counterweights, but if you use a lighter-duty camera mount you may need to balance it with a weight opposite the dish. Some larger pan/tilt mounts do exist, and some apparently have built-in position sensors. Mine just has 5 wires for control. One common, and one for each of the 4 motion directions.

My control box was also slightly different than what SARCNET used. I had a slightly different Arduino, and I couldn’t find the Triac control board they suggested. I ended up using relays to run the motor, which seems to work just fine. The things do make a lot of clicking and clunking at low speed and for fine tuning, so hopefully I’m not wearing them out too fast! They only cost a few dollars on Amazon, so I’m not too concerned. I’m using the same sensor suggested by SARCNET (the LSM303DLHC). Calibrating it is a little fiddly and took me a couple tries. They have a video about the process here.

My wiring is pretty messy in the above photo, so here’s a diagram of what I did:

I mounted the parabolic dish flat on the top of the camera mount, and placed the sensor at the rim of the dish. My reflector is made of aluminum, so it doesn’t affect the sensitivity of the accelerometer / compass chip. I had previously tried placing it closer to the base of the dish, but the sensor was confused by the motors in the camera mount.

For the radio system, I’m using an RTL-SDR Blog v4 on a laptop, connected to a Nooelec SAWBIRD GOES on the dish (these links give me a small Amazon kickback if you buy from them!)

I followed the Compilation and Set To Work instructions on the SARCNET website. Once the Arduino code is loaded, and I had Hamlib and Gpredict on my PC, my procedure for use is as follows (using Linux):

Ensure rotor has enough play to follow sat (check position of cut-off switches underneath)

  1. Connect SDR
  2. Connect 24V AC to pointer
  3. Connect USB from pointer to PC, Dish will rotate to Az 0, El 0.
  4. Open terminal, run “rotctld -m 202 -r /dev/ttyACM0 -s 9600 -C timeout=500 -vvv -T 127.0.0.1 -t 4533”
  5. Open Gpredict
  6. Select / open desired module
  7. Options -> Antenna Control
  8. Select target sat and click “Track”
  9. Select rotator device (“MediumDish”) and click “Engage”

Dish will run to initial Acquisition of Signal (AOS) position and wait

If serial connection crashes (rotctld window start showing errors and dish stops moving)

  1. Unplug 24v
  2. unplug and re-plug USB
  3. Ctrl-C rotctld and re-run. May need to change ACM0 to ACM1
  4. Go back to Gpredict rotator controller and re-select “Track” and “Engage”
  5. Re-connect 24v

Settings for Gpredict:

  1. In Preferences -> Interfaces -> Rotators
  2. Host: 127.0.0.1
  3. Port: 4533
  4. Azimuth type: 0->180->360

Recording and processing the satellite pass is the same as with a handheld dish. I use N2YO.com to look for upcoming passes (Select your satellite, like NOAA 18, click on “10 Day Predictions”, then “All Passes”, and look for ones with a high El number for the max altitude.
My procedure for each pass is as follows:

  1. Open SDR++ on the laptop
  2. Select the SDR device (sometimes I have to refresh), make sure the sample rate is as high as you can go (2.56Mhz for the RTL-SDR) and click the Play button at the top.
  3. Make sure the BIAS-T function is checked. Sometimes I need to do this several times to get the power light on the SAWbird filter to come on
  4. Set the gain, I sometimes start with max and drop it as the signal improves, or you can use AGC or whatever works best for you
  5. Set recording settings to Baseband, WAV, Int16
  6. When the satellite is in view and the antenna is tracking, click “Record”
  7. When the signal drops and the pass is over, stop recording
  8. Open SatDump
  9. Select the appropriate satellite pipeline from the list at the top
  10. Set the Input File to the baseband recording I just made
  11. Set the Output Directory to wherever I want the images to go (I usually make a new folder for each satellite and pass)
  12. Make sure the Baseband Format and Samplerate are the same as SDR++ (this should automatically update once the Baseband recording is loaded)
  13. Click Start
  14. Once the processing is done, open the Output Directory and see what I got!

As with all of my projects, this too plenty of trial and error, and didn’t work right on the first few tries. Eventually everything came together and worked smoothly! I’m looking forward to repeating this with some other types of antennas, like VHF/UHF Yagis. I’m also planning to do a bigger dish in the near future!