Category: amateur radio

Shack-In-A-Box: Onboard Power

In a previous post, I documented the build process of my ham shack in a box.  Notably lacking was a power source to power the box, and this was something I decide that I would add and document in a later post.  Initially I though I would pull the server supply out of this box and mount it to finish out the calendar year, then purchase a solution like the Samlex closer to next year’s Field Day.  However, I decided instead of coming up with ways to mount two separate power supplies I would save myself the time and trouble and acquire the samlex supply this year.  There were issues with noise on the 80M band and I’m pretty sure the power supply was at fault.

After searching the current market offerings, I selected the Samlex Desktop Switching Power SEC-1235.

This power supply was selected because it was relatively featureless, and could provide 30 amps continuous, and 35A Peak.  With the onboard power monitoring and the way I intended to mount the supply, there was no need for the SEC-1235M model, which has its own onboard voltage and amperage display.

Samlex sells a mounting rack that allows you to mount a radio together with the power supply and I co-opted this idea for my mount. First, panels were drawn and a shop favor invoked for them to be cut on the water jet.  Then, I purchased keystock to mount the panels to, and to mount the power unit to the shack in a box.

Keystock drilled and tapped, panel holes cut & drilled

Keystock mounted. Need flat head screws for flush mounting.

Removing the factory screws and using original holes to mount the panels.

Another view of mounting the panels

Final Mounting

Another View

Fitted into the shack in a box

 


Shack-In-A-Box: Initial Build



What’s the point?

Go boxes exist across for a spectrum of purposes. Perhaps you have a sewing box, or a toolbox, or a box with everything required for D&D. By doing this, you have everything needed for that particular task and can be ready to go within a few moments notice – or not have to get everything collected for Friday’s game and you’re already late. Building a ham radio go box is no different – you can grab the unit, head out the door and and once on site have everything you need to operate.

I am primarily a portable operator (as a result of my HOA) who must set up each and every time. With a go box, having all my radios are mounted in a single portable box with the radio gear and power connections set up means I will have much longer to operate – and that much more isn’t left to chance.

I was inspired to build my go-box after joining the Ham Radio Go Box group on facebook. I ended up throwing my new 2m mobile in there as well as a result of starting to run my club’s monday night net. Here are pictures and remarks of the process.

What’s in the Box

Check out the for pictures. In the go-box, I have

  • HF + 2M/440 by the Yaesu 857d
  • MFJ 929 HF tuner connected to the Yaesu
  • 2m/440 + Crossbanding from the Alinco DR-735t
  • Built in illumination for dusk or after operations
  • Built in cooling for both radios
  • Onboard 120V power conversion and a power monitoring system for amp load and voltage (voltage is monitored on battery power)
  • USB Phone charging

Build Log

I drew an initial layout in cad to determine if I should purchase a 4u or 6u rackmount case. The rackmount system comes from the portable audio world and specifies a certain amount of space and a mounting system. Trying different variations, it was decided that a 6u box would provide for all the equipment I had currently, and some future expansion. I decided that purchasing a commercial rackmount would give me better results then building my own box as I have seen some do.

Ultimately, I selected the SKB 6U Roto Shallow Rack unit over a comparable Gator Box (or eurolite) for two reasons. The first was that the SKB features an internal gasket that while it won’t make the water proof, will certainly help keep out the spirit dampening rain storm. The second was that the SKB was better reviewed then any other rack mounts I had found. The additional sturdiness of the unit was worth the additional expense. I avoided the particle board solutions by Eurolite & Musician’s Friend due to the weight. Both the wood and plastic boxes are flight rated so there should be negligible difference in their durability with the weight of the poly boxes being at least half the weight of their wood equivalent. Radios & other things will make the box heavy enough on their own. Then, I needed to go from the vertical pillars of the rackmount system to a horizontal surface to mount the radios, tuner, and other gear. To rack them into the go-box, I ordered 1u racks from Navepoint. By ordering directly from Navepoint I saved about $2 each rack, exchanged an email for another $5 off, and still had free shipping. Much cheaper then purchasing from Amazon


I used the mounting brackets provided by yaesu and alinco for their radios. No reason to reinvent the wheel for a custom solution when what was provided works well. The radios were mounted in the slots in the navepoint shelves with the brackets that came with the radios from their manufacturers. You’ll note that at times the radio shelf is clamped a small masterforce vise. This method of keeping the shelf vertical to work on it works fairly well, especially when you let gravity work to your advantage. This is my go to method for handling the shelf when it is outside of the box.





A Blue Sea Systems 6 Circuit With Coverwas sourced from amazon. This helps protect the radios from short circuits with fusing, as well as providing a neat and clean way of distrubuting the power from whatever source I am using. I should note that its built with metric standards. Because of this, i found it a bit difficult to work with as I have minimal metric tooling. An initial fitting was done to make sure I was on course with the space requirements of everything so far. (I apologize for the potato phone pictures.)



Because of my desire to run the system from a battery, I ordered DC Shunt Monitoring System from amazon. I chose this particular model as opposed to the some of the meters around for its low draw – and that I can shut of the monitor and have no draw at all. The system displays the current voltage of power system, amps in use, watts, and watt hours. I needed a way to encapsulate the shunt, so I designed and 3d printed a shunt box that would allow me to mount the shunt in any orientation. The bottom of the shunt box has two hex hole for a 6-32 nuts to press in. The top has holes for 6-32 fasteners to fit through and tighten via the 6-32 nuts. The center hole is to bolt the shunt mount on the frame with a 1/4-20 bolt. STL below. There are tunnels for the main power wires and the display relay wires.





To mount the monitoring display, the power switches, and a USB charging port, I needed a small panel about the size of a 2u panel (3 1/2″ x 19″). The layout of the switches, power display, USB Charger, and control switches was mostly laid out on the fly. After layout, cutting, and test fits the board was sanded through to 400 grit and stained. Rustoleum Spray Lacquer was used as a protective coating. I found that laying the piece out horizontally and using heavy coats resulted in the best surface finish.

Each function of the box (such as the radios, the usb charging ports, the monitoring display) can be switched on individually. I sourced a number of 13.8 VDC 25A switches from Digikey instead of using lower amperage switches and relays – again with battery powered operation in mind. Because the switches were designed to be mounted in thin plastic, not plywood, I needed a way to engage the locking tabs on the switches on the board. Switch mounts were designed and 3d printed to engage the locking tabs on the switches and screw into the face of the board. The monitoring display was also made to be mounted in thin plastic or steel, so a frame for that was also designed and 3d-printed.




To keep the wiring neat and tidy as I run it to the switches, power supply, and more small wire mounts were designed and printed with my monoprice. An 8-32 nut is pressed into the slot, a #10 fender washer is placed in the top, and then it is bolted onto the tray with a 8-32 x 7/16″ machine screw for wires to run through. This helps keep the wiring tidy and supported.



Adding a feature I probably don’t need, stick-on LED tape was installed around front of the box. First the surface is prepped with isopropyl alcohol and then allowed to dry. The LED tape is applied, leaving the power leads in a supposedly convenient position. Deans Connectors were ordered to allow me to connect the switching panel to the LED tape. With these connectors installed, it becomes trivial to disconnect the lights from the switch board. High quality adhesive shrink tube was applied over the solder joints to protect against shorts.

After this, I began the final fit up and cable management of the wiring inside the case. This was fussy, test, trim, retest, retrim, crimp, retrim, install, remove work that consumed the better part of four days of work. Cable management is an important part of any job and I didn’t want wires hanging in loose bundles looking like garbage – hence printing and installing the wire mounts. Here you can just see the power feeds for the radio fitted over the top of the shelf. They are then fed down through the slots in the trays to each radio. Later, I realized that I needed to open up the slots as an powerpole can’t be pulled back through. Two of the ventilation slots were cut to form a generous slot to pass the powerpoles through. These were cut with a dremel, and then some hand filing to clean up the holes. I also needed to remove a section of the top rack on the side so that wires could pass out from behind the distribution box and make the required connections. Again, this was cut with a dremel and then hand filed.





I had to decide how to hook up the radios – whether I was going to use the factory connectors or powerpoles. I ended up with a mix of the two. I removed the alinco connector and switch the radio directly to Anderson Powerpoles. For my 857, I decided to keep the yaesu connector because of the brown wire (a stupid item imho but best to leave it). Powerpoles were installed on the drops, then a generous coating of dielectric grease was applied. I’ve read that powerpoles corrode quickly so this will help keep them from oxidizing without damaging the ability of power to flow across the tabs.


Axial fans were ordered to provide additional cooling to the radios. The fans from digikey were selected to to provide maximum airflow with a low 38.5dBA noise. If needed, I can mount a rheostat to slow the fans and lower the noise, at the cost of airflow. A fan mount was drawn in cad, and a shop favor called in for the panel to be cut with a water jet. Once it came back from the shop, a coat of rustoleum professional grade primer and then rustoleum gloss black was applied. I refuse to utilize krylon paints in my shop. I broke a fan blade just by tapping with with my finger, so I clearly needed to provide some protection to the fan blades. A fan cover mirroring the style of the grid on the fan mount was designed and printed. I reasoned that the fans could push no more air then they could pull, and mirrored the design of the fan mount. To save print time in the future, I redesigned the guards to have a sleeve and cover. While the sleeve adds slight complexity to the walls and increases their print time, it will save roughly 3 hours should I need to redesign or reprint from breakage the guard grid in the future. Here are the sleeves, and the first & second iteration of the guard. Printing with just shoulders pressing against the fan saves an hour of print time on the monoprice.

Small rubber grommets were ordered and 3/32 holes appropriate for the grommets were drilled. Grommets installed, the wires were passed through the side of the guard, and then wired in parallel to a deans connecter which was then hooked to the appropriate circuit. As will the led lighting, this makes it easier to service various parts of the box. The fans are attached with 6-32 bolts and acorn nuts for a finished look. The fans pull air from the rear of the case and push it towards the front. The user of the go-box experiences a slight breeze.











A “rack” of sorts was designed and printed for the MFJ-929 HF Tuner paired with my Yaesu 857d. This rack barely fit on my monoprice – I had to set the bed size to 121mm x 121mm and get rid of the brim to print these. Taking advantage of rapid iteration through 3d printing, here is the mark 2 version of the tuner mount mount, which loses a mounting hole on the base, and eliminated the need to drill and tap the side of my tuner as I had originally planned. A slot that fits to the center screw on the side of the tuner helps center & retain the tuner in these mounts. Then, a sliding armature was designed that will insure the vertical retention of the tuner.

With the initially printed arms, I had issues with the print warping, and the arms tilting back. I lost some faith in the retention ability of the arms because of this. I initially planned on printing the arms in a way that they couldn’t warp from heat differences as the layers were applied. I changed from the initial arm design to Mk 2.5 to help reduce the print time, and to make things look nicer. After a test print with the arm at about 15° on the print bed I decided I didn’t like the results when I cleaned up the print. So instead, I printed two more arms, gently heated the pla prints, then pressed down with a wood slat to intentionally warp the print so that when bolted onto the mounts, they would squeeze down and against the print. Mk 1 & Mk 2 below.

The fan panel makes it harder to get to the pl-259 jacks on the back of the radios. To make it easier, I ordered and installed some right angle adapters to the radios. The 857 was connected to the tuner with a cable that has a right angle connector.














Closing Thoughts

At this point, I’m posting the build log. I will have to make a few updates for things such as integral power supply, hand mic mounts, and the smaller 2M antenna I’m building to keep in the go-box for deployments. However, the go-box itself is practically done.

There are a few things I will do differently for the next build. I would have a smaller switching section. The parasitic draw of the radios is not enough to justify the cost & trouble. If I was doing a SOTA where I had to hill climb for this, I would take a Yaesu FT-817nd or Yaesu FT-818. Still, for this box I think it all works well and I am in no hurry to tear everything apart to make Mark 2. Even though this is less of a go-box and more of a shack in a box I’m satisfied with the result.

Gallery

Go Box at Field Day

The go-box’s first deployment was the ARRL’s 2018 Field Day. Note that the tuner is retained by string and that the power supply is external. I simply ran out of time to get everything done.

Operated with my W4KGH End Fed Antenna (Doc 1, Doc 2) with 9:1 Unun, 55’ radiator & counterpoise. Worked well on 40M. 80M was barely able to tune. The noise floor for 80M was S5-S9 though so I was unable to hear anyone.






Random At The Bench

I had an issue with the amperage display reading incorrectly. Here I am verify the wire and testing its reading against my fluke 87V.


Parts

Ordered Parts

  1. SKB 6u Shallow Rack
  2. Blue Sea Systems ST Blade Fuse Block
  3. NavePoint 1U Racks
  4. Switches
  5. PowerSupply
  6. DC Shunt Monitor
  7. 12V Warm White LED Strip Lights
  8. 18 Gauge Stranded Hookup Wire, White
  9. 18 Gauge Stranded Hookup Wire, Black
  10. Deans Connectors
  11. Shrink Tubings
  12. Case Fans
  13. 90° PL-259 to straight PL-259 cable
  14. 90° UHF adapters
  15. Rubber Grommets

Printed Parts

Note: I have chosen to provide many of the solid model STLs for the 3D Printed Parts I used. 3D Printing is an incredible technology, and I amazed to be able to use it so easily. However, I provide these STLs without support. I may have suggestions or warnings but they are provided as is. I hope that they are useful to you, but they may not be.

  1. Switch Plates
  2. Wire Guides. Note – max capacity is 4 12 gauge automotive wires. A 8-32 x 7/16″ bolt will rack these perfectly with no interference to the wires with a .050″ fender washer and a 14 gauge steel shelf.
  3. DC Shunt Box STL’s
  4. Fan Sleeve
  5. Fan Cover
  6. Tuner Mounting Fixtures

Creative Commons License
These STL’s are licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License. I do not certify anything other then loosing your beer money over these. They may or may not be useful. Remember, only Hu can Prevent Florist Friars!


Alinco DR-735T: Initial Thoughts

I recently purchased a new VHF\UHF radio. I intend to purchase 2 of the same radios, one of which will reside in my go-box and one which will be installed in my new car (that I do not own yet). One of the things that attracted me to the was the crossbanding feature.  Another was that it was not yaesu\icom.

Another one of the things that attracted me to the Alinco’s DR-735 Clone Utility was the programming software … which is actually terrible and undocumented. I’m going to relate a few things about the programming software as I haven’t seen any documentation.  Hopefully this will help someone having a bonehead day.

First – it requires .Net 4.5 which is happily installs … with a japanese installer.  Good thing we just keep clicking next right?  Ugh.  But it does actually install, and run.

Configuring channels is hard – let’s export from my CHIRP config and remix that to import as the clone utility.  But … it appears that the cvs import is broken.  I received strange errors like “Subtone NG : Line=3” until I managed to craft a CVS file that the program was happy with:

Once I was able to edit my cvs file to match the exported format from the software, … I was barely able to import simplex channels. I could not load repeaters from the cvs file (even one that was exported by the software itself). I don’t understand the problem and ended up putting in the first memory manually. Copy/paste does work though, so once you struggle through setting up the first repeater you can copy\paste and then edit the rest:

But here’s what really screwed me up (for to long).  If you’re working on a smaller computer, like a netbook you’ll get a cryptic error message.  If you’ve worked serial ports before you’ll instinctively know what the problem is.   Until you get a larger screen though, you won’t be able to do anything about it.  Here’s from a VM shrunk down:

And here’s from a VM that I left at the full 1920×1080 of my new computer:
You’ll notice off in the right hand side a dropdown saying “COM3.”  Yes, that’s right.  You lose the option to configure the com port the clone software expects to use!   Once I tried a bigger monitor (for some reason the external display on my netbook goes to 1280) I was able to select the proper COM port and then only upload the first channel of my config.  Turns out you have to select all the channels you want to upload.

In my mind, the com port selection should be with the File\Write menus, not where it can get lost.  I can understand the CVS import failing (to an extent).  But a properly crafted CVS, or indeed, one exported by the program itself should import more then just the simplex options in the config.

I have to give the clone utility 1 star since it seems mostly broken.  How does the radio follow suite?  Suffice it to say I am glad I did not buy 2 from the start.  I look forward to the radio functioning well enough that I have no reservations about buying a second.


AAR: Pumpkin Fest

On October, I helped out my local ham club doing background logistics for the floats in the Pumpkin Fest Parade.  Our job was to get the floats out in the order they should be, monitor the progress of the floats through the parade, and radio if something went south.  Pretty interesting work, if a bit boring.  If you get the chance you should definitely help out your local club with a parade.

Here is my “kombat rig” that I wore while helping out.

img_3073-jpg-convert

The list of things I’d do differently is pretty short. I’d dress a bit warmer. I’ll also wear my electronic muffs. I wasn’t thrilled about cutting off my hearing entirely – if something happens I want to hear. But if the noise gets to loud it will cut off. And I should have packed some snackage to munch on once the parade got started.

Previously I had used a back pack. It worked, but it was really over kill for the situations I have worked. My car is always within walking distance, so now I prefer this super simple, light weight rig. I will be adding this radio carrier to the mix.

Parts from left to right:

  • Dump pouch
  • Organizing pouch, good for holding maps and a spare battery for your radio.
  • Baofeng Radio setup:
    • Signal Stuff Antenna. My antenna and radio are setup for BNC.
    • Baofeng BF-F8HP radio
    • Extended battery. The 8 watts really drains the stock battery. Keep it for a spare.
    • A Handset. I’ve goofed around with the throat mics, and honestly these are the best no muss solution. Quality control it yourself and make sure everything works before you hit the field, or you’ll do my screw all over again.
    • Acoustic Tube. You definitely should be using an acoustic tube so you can actually hear the communications over the din of the crowd.
  • A few nondescript carabiners for attaching things to. I had my drinking bottle clasped to my belt as well as my volunteer flag.
  • An earplug for the other ear. The noise of the crowd started to mess with me and put me into sensory overload. Not fun, and not acceptable when working an event. Additionally, when a 100 year old steam engine whistle goes off 5 feet in front of you, you’ll appreciate the lowly ear plug..

Building a Ham Radio Power Supply

Ham Radio Isn’t Cheap

Much like shooting, ham radio is expensive. I think all fun hobbies are. But after spending $820 for the radio, I wasn’t in the mood (or the financial state) to drop another $100 to $150 on an Alinco Power Supply. Slick as spit, but not worth it.

So, here is what I came up with:

My power supply has the following features:

  • Hacker cred. I put it together, and it looks nice and works great, on 2M at least.
  • Dual USB ports, for keeping a phone topped off.
  • A cigarette lighter, for powering/charging a baofeng or anything 12V compatible.
  • Dual Anderson Powerpoles on the rear, for the ham’s favorite 12V connector
  • Uses a standard computer power supply cable.

So, here is my Bill of Materials:

A few build notes:

  • I crimped the powerpoles using my standard channelock wire strippers and then soldered them with my hakko. This gives about as good as a connected as you can get.
  • I used standard spade connectors (though mine are from Menards), again crimped and soldered, to connect everything to the power supply unit.
  • Most ham radios expect 13.8VDC, instead of the 12V this one was outputting. That’s okay, there’s a dandy reostat you can use to adjust the output power. I had mine set for 13.81V and its drifted to 13.84/5. I suspect it has to do with the construction and actually powering the unit up. However, my 857 will tolerate a +/- 10% range, so eh. I’ll adjust it again the next time I fire it up.
  • Take care when making the AC Mains connections. I am using a cut\trimmed piece of a PC power cord, with crimped and soldered spade terminals connected to the socket and to the power supply unit. I used some push on connecters to make a removable/solid connection to my socket, then put heat shrink over the arrangement to make sure I had removed and electrocution hazard, as best as possible. 14VDC will tickle, 120VAC will kill, and hurt the entire time.
  • Cut outs for the Chassis mount and PC powersupply socket were done with an x-acto knife, a ruler, and a little bit of caliper work. Everything fits perfectly. Lay out the holes you need, then visually check the marks are in the right place. Make light passes with the x-acto to cut through the plastic of the dry box.
  • This is such a gadgety thing, but it makes doing zip ties so much easier, tighter, and with practice the cut offs cleaner.

The total cost of the arrangement? Not counting the sundries I had on hand, $54.04. Not bad, a third of the cost and quite a bit more fun. You could do this even cheaper if you skipped the power powerpoles and the other features, but charging phones is good. When I first made it, I had the radio and a cut off power cord running directly to the power supply unit. It worked, and worked well, but I wanted to make things cleaner for sure.

Questions? Comments? Leave them below. 73, and good night all.

Edit: I posted this to /r/amatuerradio and generated a fair response. I would like to highlight Megas3300’s RF Choke. This is probably needed for mine as well, but so far I’ve only used this on VHF. A proper HF antenna system awaits.


Icom IC-W32A: A Work in Progress

This is contingent to my “Workin’ the Birds” Series. However, it is a more technical discussion of amateur radio equipment. The primary purpose of this blog is preserve information I want for later. However, I feel that the information contained in these posts may be found edifying for others. If you can’t look up edifying, you are not the target audience of that secondary purpose. A third purpose is a demonstration of my technical skills and abilities as well as communication. It is not working as well as I would like.

I wanted an upgrade from my Baofengs for multiple reasons and the Icom IC-W32A is the radio that I ended up choosing. The W32A is well regarding within the Amateur Satellite Radio community as one of the best. After my post on the high price and poor selection of equipment available at this time, I ended up back tracking into the early 2000’s for my “new” gear. This HT is well loved. Wear spots, but no nicks or gauges. Used, but not abused. The only thing that was missing from what I wanted (better receive, reasonable price, better channel management, S-Scale) was better channel management, though there is the option of skip programming which may prove useful.

The bad is being an ebay radio (and 10 years old), I knew I would be needing a new battery. With this particular auction I didn’t get a charger either. At this moment in time, the charger missing is a bad thing. I don’t know if the radio will even turn on. While I was willing to risk what I did on the auction, I wasn’t ready to double the bill to fail. I need to know if this thing will power on and transmit. I was able to get around this though, with an adapter from RadioShack. Two options:

Since I have all of components for option 2, I went with that. The primary reason was the low cost – $3.50 and a bit of wire and solder. You could buy an official Icom Charger, but if this thing functions well, I’ll be switching to this lithium-ion battery pack. What a waste to get the official Icom option when I’ll use it … once.

After looking around the manual and talking with people on reddit and the AmSat mailing list, I was able to determine the polarity and power output of the plug. 12V, center positive.

After charging, the radio powered up! Oh joy. I at least have a reasonably priced scanner now. Except tuning to a NOAA Weather station, I do not have audio output. Plug in some headphones, and I have sound. Great. This could be either a broken speaker, or a broken headphone jack. Without the headphones, I have a working mic. With the headphones, I do not. For now, the solution is to find a reasonably priced handset to plug in. This will work until I have checked everything else out, and insure that the radio is worth my time to repair further. It will also provide inexpensive replacement parts. The replacement will be here Monday (4/18) and I will attempt to check into my ham club net with the radio that night.

That’s all I have for now. I’ll leave this post linking various resources and information that I found while waiting and getting the radio to function to this point.

Resources

Parts

Disclaimer:

Borrowing from my podcasts, this post is not sponsored by our employers, employees, who or what have you. All opinions expressed have been, are, and always will be our own. Said opinions expressed on the show are believed to be well reasoned and insightful. If you find a topic mentioned on the show interesting and decide on further action, then it is your responsibility to research, consult your doctor, lawyer, significant other, etc and understand the full risks of such an action. Providing a link to a resource online does not certify the usefullness, safety, or reliability of the content or providers on the other side.

The information in this post is semi-technical and capable of damaging\ruining\destroying your prized transceiver. It’s not my fault if you turn it into and efficient boat anchor.

Minor Update

I’ve found that filling a bit off the bottom of the plug from radio shack makes it connect more reliably.


Amateur Radio HT’s, A comparison

Short blog post today.  This is a spreadsheet I made comparing my choices for a new ham radio HT.  Not really notable, but the result of a bit of work so I thought I would share.  Click the spreadsheet to grab it.

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Installing OpenWebRx On Fedora 22

I’m a pretty regular viewer of Hak.5. The point still matters. Hak5 Season 19 Episode 16 featured OpenWebRx, a pretty awesome web powered interface for an SDR dongle. I thought it would be useful for monitoring my ham club’s repeater. OpenWebRX is kind of limited in its use cases (to my mind) because of its limited frequency range. It neatly centers about 15 Hz on either side of the set frequency. The author states that its because of the multiuser intentions behind the software. However, that doesn’t mean OpenWebRx still can’t be useful – or fun to play with.

For my use case, I have two purposes:

  • General monitoring of my club repeater. Even though I have a baofeng docked and listening, I like the thought of it.
  • Another use is to slide down the frequency range touch and be able to test radio microphones without needing another person to phone back – plus I’ll actually be able to hear myself.

While not a flaw of OpenWebRx, the listening range of the SDR is pretty limited – at least with the stock antenna. At present, its not able to hear my club repeater. I’ve picked an adapter from Amazon in the hopes that putting something bigger then a measly 6 inches will pick up my club repeater. After attaching my 1/4 Wave Ground plane, there was noticeable improvement but it was still hard to hear the repeater. Local copies are very strong however, using my 5 watt HT.

There are no install instructions for installing from source in Fedora and there is no package within the Fedora repos. At present, you will have to use the dev branch of openwebrx for the system to run. You’ll see (if you read the ticket) that I promised the developer install instructions for Fedora. The following are the commands I used to get OpenWebRx running on my Fedora 22 headless server.


#OpenWebRx Fedora 22 Install Script(ish)
#Get OpenWebRx dependencies from the repos when possible (assuming you started with the same packages I had - you may need to install Development Tools, among other things.  I often install from source.)
su -c "dnf install dh-autoreconf fftw-devel libusb-devel -y"

#Get openwebrx source from github
git clone https://github.com/simonyiszk/openwebrx
cd openwebrx
git checkout dev #and switch to the dev package so it will run on Fedora 22

#Get openwebrx dependencies not provide by the fedora repos
git clone https://github.com/simonyiszk/csdr
cd csdr
git checkout devs #also need the dev version of this
make
cd ..

#need to build rtl-sdr from source - since udev isn't installed apparently by the repos, so .... yup, build from source
git clone git://git.osmocom.org/rtl-sdr.git
cd rtl-sdr

#build guide available from http://sdr.osmocom.org/trac/wiki/rtl-sdr
cd rtl-sdr/
autoreconf -i
./configure
make
su -c "make install && ldconfig && make install-udev-rules"

#openfirewall port since I want to be able to access this from across my lan
firewall-cmd --add-port=8073/tcp --permanent
systemctl firewalld restart

At this point you have to do some configuring to the config_webrx.py file. Go ahead and pop it open in your favorite editor, and add in the required info. One important thing to note, use the local lan address for server_hostname=. Also, note that openwebrx supports opening your server to the world. My DSL won’t support it so I’ve decided to disable that feature for the time being.

To run openwebrx, a simcple chmod +x openwebrx.py && ./openwebrx.py will get you up and going. For running openwebrx unattending, you need to use screen or tmux. Using nohup doesn’t work and creates a mess.

 

openwebrx-screenshot


Workin’ The Birds: SO-50

For a change of pace, I thought that I would try making contacts through SO-50. SO-50 is another FM repeater satellite and until the commissioning of Fox-1 as AO-85 the only FM repeater still operational.

Unlike AO-85, the uplink for SO-50 is 2M and the downlink is 70cm. Here is my channel configuration that I’m using for my baofeng. Here’s what I’ve learned since my last attempt.

  • Open the squelch:
      I was debating whether or not I would leave the squelch open in my last post. I’ve deciding now that I will.
  • Mount the antenna on a tripod:
      I’d seen about as many people with mounts as just aiming the antenna by hand. Tracking a satellite is hard, let alone managing two radios, a recorder, a time piece, directions …. I could go on.
        I’ll be mounting mine on a camera tripod from now on. I found a piece of aluminum square stock, then I drilled a 5/8″ hole through it and then a drilled and tapped a 1/4-20″ through the side. Finally, I cut it off (about 2″ long) and drilled and tapped a 1/4-20 hole in the bottom. I find that I need a small piece of flat stock about 3 1/2″ long to put between the tripod and aluminum block. Clear as mud right?

    2016-01-06_18-51-11_328

      I cut a piece of 1/2″ copper pipe (that conveniently fits up the south end of a north bound arrow antenna). Insert it in the south end, then slide through the 5/8″ hole and tighten the thumbscrew to keep it in place. When I do a day pass and finish up a few other things, I’ll dedicate a post to the subject, with pretty high quality pictures.
  • I seriously need a way to orient angles
      Like, I set of protractors or something. Its very frustrating trying to track a satellite with no clue where the angles are.
  • Higher qualities recordings are only good if they’re complete:
      Oops. I noticed that my last recording wasn’t all that high quality so I tried to improve it. It worked, but I alo managed to get skips in the recording. I guess my droid 2 is getting old. Let’s see if I can’t find a decent dedicated recorder somewhere in addition to those protractors.
  • Relax, it’s late night pass and there’s only a few people on:
      No, seriously. I did an 11pm CDT pass and there were only 3 people trying to trade. Chill people. I said they were going fast and furious but for a late night pass it didn’t hold true.

Anyway, that’s what I’ve learned from my last two passes. Also, congrats to this young lady on her first contact. I also made my first contact last night, and yes, I was pumped.


Workin’ the Birds: Fox-1A

This is a continuation/review/progress report from my previous Workin’ The Birds post. The reason is to talk a little bit about the new bird on the block, Fox 1-A and notate what I learned while I tried to listen in on one of the passes.

Amsat just put in Fox 1-A into orbit and gave it the designation AO-85.  I was able to use the AmSat Prediction Tool to find out when the passes would be. I have a recording of what I was able to hear at the bottom of the post for you to listen to if you like.

My simple setup to get the recording was as follows:

  • A uv5r set for receiving, locked to 145.980. Placed on my left pocket with the volume cranked to max. I had the squelch set to 2.
  • A BF-F8HP setup to transmit to AO-85 w/ doppler shifts, using medium power, at 4 watts. I didn’t really have anything to say, and my tracking was so sporadic (as you can hear) that I didn’t try to get into the sat. I was prepared for transmitting with my throat mic however. Using a throat mic will prevent the echo crossing on the two radios. I had thBF-F8HP sitting next to the uv5r, clipped onto my left pocket.
  • For recording, I launched a sound recording app on my droid, then slid the phone mic out into my left pocket, underneath the baofengs. It should still have been able to pick up my voice.
  • I used an arrow antenna directional antenna.

What I learned tonight:

In my previous post, I mentioned that I thought magnetic declination might be an issue. NOAA has a website showing magnetic declination and for my QTH magnetic north is … only off by 2 degrees.

Rotating the antenna along the boom can make quite a difference in receiving ability.

I would debate the value of leaving the squelch open. In the future, I’ll set it to 1 or 2. When you get close to the satellite it will open the squelch, letting you know you’re in the neighborhood of what you’re aiming for.