Images from ARISS SSTV Event

Just listened to the last pass from the ISS SSTV event. I suspect that this was ended a bit early as the signal dropped off completely mid-pass. Here are the images I received since the last post:

These were received using my VHF/UHF base station using the Ed Fong Antenna and the IC-7100 along with MMSSTV software.

ARISS SSTV Images from the International Space Station

SSTV images are being transmitted from the ISS through December 31st at 17:05 UTC. There are a few YouTube videos available showing the process even as live streaming events. Before bed last night, I fired up the IC-7100 along with MMSSTV Software on 145.80 MHz and left it running. This morning and after several ISS passes I had the following images waiting for me:

I’ll keep running these today and hope for a decent pass. Next one is in 45 minutes but is very low angle to the QTH.

Moxon 2.2 Ready for Deployment

Version 2.2 of the Moxon antenna is ready for a calm day to test. It has been very breezy here of late but expecting good weather tomorrow to try and set this up again. Version 2.2 has a newly printed Hub. The last hub was made with PLA and cracked after 24 hours. The new hub is printed in PETG with an Octet infill. I also designed the center to nominally be at the 7m Spiderpole height. I can add an adapter now to move it up to 9m with no other changes to the hub.

Printing the hub in PETG took 20 hours and uses up about half a roll of filament. Warping looked well under control for about 60% of the print. I started noticing some small warping at the ends. When the print was complete both ends had about 1mm of warp. This was enough to through the pole adapter holes out of round by about 1mm. I modified the pole adapters by this amount and reprinted them in PETG. They now slide in quite nicely and are held in place with #6 screws.

I had difficulty on the last go around in the pole adapters fit to tightly inside the fishing poles. One of the pole tip adapters would not come out of the fishing pole. I used a 3/16″ piece of steel rod from Home Depot to pound it out with little difficulty. I plan to sand down the pole adapters a bit before the next setup but they will likely still fit a bit too tightly.

I also opened up the holes on the wire clamps to give me a bit more freedom to adjust the wires on the fishing poles. These I printed in PLA as before.

My current plan for tomorrow is to setup the 15m Moxon at 23 feet. I am going to attempt to adjust the pole tension this time using Kevlar kite string with the intent of have the fishing poles in an “upside-down umbrella” configuration. Pretty much every Moxon I see on the internet has the poles bent in this fashion. I do this with the poles at full length for 20m. Once this is set I’ll add the wire elements and start testing.

Moxon Structural Issues

I brought the Moxon down today after having it deployed for 24 hours. The only physical issue I found was that the Moxon hub cracked where the pole adapters are inserted.

I’ll have to redesign this yet again. One additional feature will be inserts for the center diameter allowing me to set this up at different heights with an adapter. The pole adapters fit very tight inside the fishing poles. I could not remove one of them. I may have to sand them or worst case print them again a bit smaller.

Moxon 2.1 Test Results

Very good performance on 15m with Moxon 2.1. First up made the WSPR Challenge board after only 12 hours of operation. Came in at #41 with 67 unique spots or the top half of the spots. As of this morning and with 24 hours of WSPR operation I have 92 unique spots which would put the antenna in the top 20 WSPR Challenge spots. Significantly many of the spots are pointed right into Europe this morning which is exactly what I wanted to see. Here are the recieve spiots:

Here are the 20% transmit spots at 1W:

I will play around with this antenna a bit more today but will need to bring it down later this afternoon as winds will be picking up. I also want to check how well the mechanical components have stood up over night.

Moxon 2.1 Is On the Air!

Antenna weather returned to South Texas just as previously advertised. I got an early start this morning and fiorst took down the EFHW antenna which was gathering some WSPR data on 20m. I made the 20m WSPR Challenge board yesterday at #88 with 188 unique spots.

Once the EFHW was stowed away I tried best as I could to straighten out the aluminum angle I use as a support for the mast. It’s better but still needs a bit of work. I re-installed the Spiderpole and set the new mast clamps, guy ring and Moxon hub. First issue was that none of the mast clamps were the right size. Not sure what happened there but I had to take them all off. The guy ring and hub worked fine. Next up was installing the pole adapters into the fishing pole spreaders. These tuned out to fit much tighter than I had anticipated and I had to pound them in a bit to fully seat. It may be the outer sleeves I added to the fishing pole ends may work a bit to well. I then installed each of the poles in the hub and placed a screw to hold them in. One adapter would not fully seat but I left it in as it was plenty tight. I extended the fishing poles to full length and added the wire clamps to each pole. Next was placing the wires in place. I had previously measured each wire and added a cable tie to mark the appropriate position. This is where it gets interesting as adjusting the wires also creates tension on the poles. This time I opted not to use Kevlar string for added support and let the antenna wire do the tensioning. Here is the antenna after these bits were completed:

A quick test on the antenna analyzer showed things generally in band and this improved when I further adjusted the wire clamps. I will likely need to open up the holes in the wire clamps for more adjustment range. I put in my hard hat and sent the antenna up to about 9m and guyed it down:

Here are the SWR and Impedance plots once this was fully deployed:

So the antenna deployed well and initial checks looked good. I went into the shack and found little SSB activity on 15m. I called CQ and was answered by a station in Michigan who reported me S9+10 on 100W. We talked for a bit and then I switched over to FT8 and generally found good signals into Europe as before. The arc in the image below is basically centered on the heading I have the antenna pointed to.:

I am currently running WSPR and collecting spot data. Looks like the antenna is working pretty much as expected. One area I’ll like experiment with is the use of the tension lines and I may need to modify the wire clamps a bit. Overall happy with the results so far.

Moxon Testing Poised to Continue

I have been on weather hold on the Moxon testing due at first to breezy conditions then a frontal passage over the weekend. Looks like tomorrow will be great antenna weather here in South Texas so I plan to setup the Moxon 2.1 on 15m for testing. I’ll be using the original fiberglass fishing poles as spreaders this time to see if this eliminates the tuning issues I had last time with the carbon fiber poles (thinking about how to objectively test this but am coming up with very few ideas…).

Here are the 3D printed components for the antenna:

I printed some mast clamps for each of the sections which I will try our for the first time. The pole adapters were reprinted in PETG for strength and heat resistance. The hub and wire clamps are reused from last attempt.

I setup the EFHW on a fishing pole in the same location and am collecting WSPR data which I can then use as a comparison once I get this setup. I may reseat the aluminum channel I use for a mounting point as the ground is somewhat soft after the rains and is leaning a bit off of vertical.

A Tale of Two Benchys

I ran two 3D Benchy models through the two printers just to evaluate the overall print quality of the the two printers and types of filaments. The following image shows the Benchy model printed in PLA on the CR-10S and in PETG on the Ender 3 with all metal hotend and direct drive conversion:

Overall, both prints came out very well. The PLA version displayed a bit more low level detail and resolution vs the PETG version. I thing this is more material related rather than printer related. Dimensionally no issues, nor issues with bridging or oozing (i.e. stringing). So far pretty happy with the results now.

Stuff I am working on

I will likely be out of pocket Saturday and Sunday so I’ll not try and deploy the Moxon until Monday. Very windy today and rain likely tomorrow. I am printing pole adapters in PETG on the Ender 3 and am using Cura slicer. So far three sets have printed perfectly. I am impressed with how cleanly I can remove supports.

I have also pulled out my Raspberry Pi project and am working on the mounting into the Apache case from Harbor Freight. Build-a-pi is happily installing now on a pi. The goal is a portable computer for Field Day logging and digital modes.

Creality CR-10S Upgrades

I installed a bed leveling sensor to the Creality CR-10S today along with an upgraded glass build plate. The process went very smoothly including the installation of the new Unified Firmware. I managed to print what may be the best 20mm calibration cube I have ever had after this upgrade. Next up is the installation of the Microswiss direct drive extruder and all-metal hotend which will allow me to use additional materials on this printer.