Some images from my HRPT Fabric Parabolic antenna

 Here's a Video of Metop capture process using the fabric folding parabolic antenna, really great signal and locks on for a big pass. It is much easier to capture images than using a traditional big old metal satellite dish which is heavy and difficult to maneuver, witht the fabric parabolic antenna my arm does not ache and I am able to focus more on directional accuracy and also the phone screen giving signal strength feedback:

 Hi there, just a short post for some images I have captured using my Fabric Antenna. So far I have had success with:
Inmarsat 1.5Ghz
Meteor HRPT
NOAA HRPT
METOP AHRPT
S-Band HRPT
X-Band QO100
S-Band QO100

I have some other success with other satellites (Globalsat etc) which I don't feel I am ready to share just yet. Anyway here is my antenna invention, i'm very proud of it, and it's great seeing all the diverse supporters who have bought one from me & seeing other people figure out new ways to use conductive fabric for antenna creations.

 Here are the images

1) NOAA HRPT (tree cover in my area affects the most northern orbit)

2) METEOR HRPT (Overall a nice big capture all the way down to africa and the Azores in the Atlantic)

3) METOP AHRPT (Capturing & processing this big Metop 6Mbps file using just my mobile phone was so pleasing to see it all work out who knew phones could process like a desktop)

 

Why develop a space pen when a pencil will do? Thanks for reading.

Diy Gatr Ball Antenna for QO100

I wanted to see if i could make a working version of the Gatr ball antenna typically used for geostationary satellites, it is often seen at military sales shows and at fancy trade shows, i heard these types of antenna sell for $150,000? Well I thought surely i could do it myself.

I have been making fabric parabolic antennas for a number of years now. 

They work really well, I am regularly receiving HRPT and QO100 satellites via software defined radio using this method. Have a look at my ebay listings if you are interested in one. its super lightweight and portable allowing me to receive HRPT satellites one-handed using only a mobile phone.

Anyway I figured why limit myself to this parabola type of antenna, why not try new possibilities. So I have always been interested in the cool looking Gatr ball antenna but because it is difficult to see inside and understand how it works how would it be possible to know what is inside making it all tick. 

It was after seeing this image showing the dish that I thought I should give it a chance and see if the fabric for my folding parabolic antenna will work in this scenario.

So i bought myself a nice big beachball, hacked it open and stuck a fabric reflector inside. here was the resulting prototype number 1:
 

Here you can clearly see a fabric reflector inside and a LNB receiver on the exterior. I used this to test receive QO100 voice signals. To stretch out the reflector i used a number of elastic anchor supports i made and glued inside. Once I had it all fixed in there I closed it up and sealed it so I could inflate the ball.

So onwards I go to a bigger larger version:

This one worked much better. the ball radius was significantly larger than my first one and this improved the receiving signal to a level i could confidently listen to QO100 voice.

 Here we can see an example of QO100 reception using the XL ball antenna i built. It works excellently for a beachball ;) I attached tethering lines and weights to secure my antenna in place as the satellite is stationary and not orbiting so i do not have to worry about tracking it.

Transmitting is also possible. I 3D printed a combined tx/rx helical feed/LNB and using Adalm pluto SDR with a power amplifier i was able to transmit test signal. 

Overall I am happy with my setup. I achieved my goal of receiving a satellite with a homemade Gatr antenna, and I feel that this was a sucessful experiment. 

 

Further experiments are also possible using the fabric antenna method such as nasa's rovers using UHF collapsible fabric antenna which uses a quadrifiliar helical format. Here on earth we could make LRPT fabric folding helical just like QFH antenna.

If you would like me to make you one please get in touch via my ebay page in the links above.

Thanks for reading.

Updates on Portable Satnogs

 

 Here is an update on my portable satnogs rotator rig. 

I control using Bluetooth, and Stream data over Spyserver.

All runs on 12v either batter or PSU. 

Antenna is collapsible, tripod is colllapsible, rotator can be removed. 

Youloop + Preamplifier = HFmazing

 It was that time of year just now, Black Friday - Cyber Monday. I found a great deal on a Youloop antenna which included a little blue preamp box. 

My HF 0.5-30Mhz experience has exclusively included an RTL-SDR dongle and an Airspy Mini with Spyverter upconverter. I used a random longwire with balun stuffed in my attic and thought I was getting ok reception. However I can now confirm that it sucked horribly and my new youloop with preamp antenna is quite simply amazing. My HF experience is what I consider to be incredible. I would never think it possible to receive so many signals so clearly and noise free using an indoor antenna, but here I am raving about it. I feel like I have been given a new gift, a feeling of joy excitement and love for radio.

I am not or have ever been paid to endorse things so I hope you can understand when I write so highly of a piece of equipment. Using the Youloop and preamp with airspy mini + spyverter is just mindblowing. Go get one and watch your SDR waterfall light up and come alive. 

With the Airspy mini + spyverter & Longwire unun it is: Meh....
With the Airspy mini + spyverter & Youloop it is: Uhhhh this is interesting....
With the Airspy mini + spyverter & Youloop + Preamp it is:Hollllly Sheeeeeeeeeeeee!!!!!

I can't really say much more, i'm getting 80m Ham crystal clear, Volmet, DX, SSTV, So so much.

Buy it and relight your love for radio.

Updates on portable parabola antenna

 Just a quick update on my portable parabola design. From the first version I wanted to add a few features such as
-having the coax go through the centre tube and have a connector at rear.
-using a solid tube for the whole centre pole to increase rigidity over the first version
-designing various feed horns, at the moment i have feeds for 1.7ghz(hrpt), 1.5ghz(inmarsat) and 10ghz(Xband).

For a 1 Metre parabola the weight is around 350g and the pack away size is very satisfying.

redesign images are below. I find the more I make redesigns the more time consuming manufacturing becomes, I might sell as a kit thus putting the build time upon the buyer.

X-Band LNB for receiving QO-100 sat

 

X-Band LNB mount

iteration using 3D printing design

magnetic holder for phone

coax connector at base

Thanks for reading.

Parabola design

 For a while now I have been designing parabolic reflectors for Space satellite research purposes.

One of my favorite parabolic antenna of all time is the erectable S-Band antenna used by the Apollo 12 space mission.

A super lightweight highly engineered device.

It's purpose as in the description was to be a compact erectable antenna which would open out into both a receiving and transmitting antenna to send and reeive S-band frequencies directly from the Moon surface to the Earth.

So I have been looking into it to reproduce.

Here's my working functional prototype. it is 1m diameter and the feed is desgned for 1.7ghz reception of weather satellite data.

Slide arm design.

at it's full erection.

Here we see the opening and closing in action.

Anyway, i'm forever continuing the iterations and it's functioning better than i expected. I hope I did NASA proud :)
Oh and i'm now a fully qualified certified Devops and Cloud computing specialist. Go me!

Thanks for reading.

HF Airspy Mini + Spyverter + Random Long Wire

 

Hey you. Look what I got. Thats right, I got an airspy mini & spyverter :)

I have had the airspy mini for a while now, I use it for listening to satellite communications. It seems to be my go to SDR, having also a RTL-SDR and an SDRplay RSP1. I won't go into reasons why it is my go to more than that it is more able to pick up signals and is more user friendly with my computer, and has bias tee.

my rtl sdr HF usb dongle - beginner level on HF?

I wanted to see if I can extend it's capabilities to using HF bands (0-30Mhz) just to be able to explore RF and learn a bit more. I tried with my RTL SDR HF dongle which gives basic results (0-14Mhz) but lacks bias tee and has EMF noise in the waterfall, the SDRplay has good potential but it is so terrible at integrating with SDR# or SDR++ on Linux or Mac it is just not worth going down the Rabbit Hole; if this issue is sorted then I might come back to SDRplay.

So, I bought myself an Airspy Spyverter last week and here are my first impressions. I bought all devices myself and I am not doing paid promotions or product endorsements.

Firstly, the Airspy and Spyverter do not come with a printed manual, so you must research ho to hook it all up correctly or else you could damage the devices. I connected my Airspy Mini & Spyverter up like this:

note the position of the micro usb socket on the spyverter. It helps to know this for orientation. Also it is suggested not to connect usb power to it while at the same time using bias tee power, as it might cause damage.

I get it connected like this:

I stuck on the self adhesive heat sinks to the airspy mini as i was worried about the amount of heat it produces - I am told on forums that the very high heat is a normal feature of airspy mini, similar to the heat produced from running Jetson nano's, Raspberry pi 3's or 4's wihout heatsinks or fans attached.

My antenna for basic first time HF reception is a random long wire antenna connected to a 9:1 unun. I use over 16m of wire for the main element, and a few metres of wire going to a grounding source which is supposed to reduce electrical noise. in between I use a self-made unun/balun using a ferrite ring, wire, and connectors housed in a plastie box:

my homemade 9:1 unun/balun

And so onto the results of the Airspy mini + Spyverter HF combo. Am I pleased?

Well, it's a mixed bag. I am only a week or so into using it so perhaps I have not got the setup creases smoothed out yet. 

Things I like about AirSpy Mini + Spyverter:
1 - this combination gives me the HF 1-30Mhz I was looking for (the rtl-sdr only does 0-14Mhz HF).
2 - the gain controls seem to actually have an effect on signal performance.
3 - it is more straight-forward to get up and running receiving signals.
4 - it has bias tee power.
5 - I am definitely getting more radio stations than I did with either RTL-SDR HF dongle or RSP1 dongle.
6 - The stations I get are more clearer than when using either two other dongles.
7 - using the Airspy Mini + Spyverter with SDR# software, it is the best combination I have used to fine-tune audio and noise reduction to achieve clear speech even in high static, faint HF radio stations. It almost seems like a magic trick sometimes.

Things I am yet unsure about Airspy Mini + Spyverter:
1 - Is my location in the centre of a busy built up urban area causing me to pick up more EMF and RF noise using the more sensitive Airspy mini?
2 - What is causing the different wave pattern in the SDR software?
3 - Is my antenna sub-par?

Using the various SDR devices I own, they all produce different and varying outcomes on the RF waterfall of various SDR computer software. As a mostly MacOS user I have used GQRX, CubicSDR, SDR#, and SDR++.

I tend to use different software packages mostly because as yet, I haven't been able to find a one-for-all complete software package yet. SDRplay devices are the big stumbling block here. My RSP1 I can only get working using CubicSDR on Mac or SDRuno or SDR# on Windows 7/10. I  very rarely use my RSP1 maybe once a month I take it out the box, and that is just to compare against other devices.

SDR++ comes close to being the most one-for-all complete package, but as yet, it does not have the magic audio processing that SDR# has. And as you may realise, SDR# is a Windows only package. Having a Mac version would be tremendous. Many people would be happy.

So onto my signal tests.

Using my Airspy Mini + Spyverter combination, it does undoubtedly produce lots more radio stations and listenable signals for me than my other devices. It is as simple as that.

However I am now contending with some other things which I want to know more about and try to find solutions for.

Mostly. What is causing these RF peaks?

When I read up on HF sdr, I saw waterfalls which looked like this:

Nice, flat spectrum, with nice clear well-defined station peaks. 

Using my Airspy mini + Spyverter setup I get this:

I get the nice clear well-defined station peaks. But I also get this huge fat arch of doom. Why do I get this? What is causing it? Why! Why! Why! My life!

I don't get this result using RTL SDR HF dongle, but I also get fewer clear stations. Here is my result using RTL-SDR HF dongle:

 

Is it because the Airspy mini or Spyverter is damaged?
Is it because the Airspy mini and Spyverter are more sensitive to ALL RF signals including noise?
Is it because of my long wire antenna?
Is it because of my location and my antenna position (in the attic of my end terrace urban house)?

I can reduce this mound by reducing the airspy mini gain to level zero or 1, but also I reduce the clear stations too, they are synchronous:

Airspy Mini + Spyverter set to Linear gain level 16:

 

 

 Airspy Mini + Spyverter set to Linear gain level 8:

 

 

RTL SDR HF Dongle set to max gain level 49dbi:

Using Airspy min + Spyverter this mound also exists all through the HF reception, an example at 7Mhz is here:

I have tried to correct using:
- Ferrite chokes on the wires - no noticeable difference

Then:
- Testing on a different computer, a laptop:

Laptop - Airspy Mini + Spyverter + Long Wire antenna set to Linear gain level 16: 

 Laptop - Airspy Mini + Spyverter + Long Wire antenna set to Linear gain level 8:

 It seems to be a different RF noise pattern than with Desktop computer. So what now?

- Testing with a different antenna:

I try also using a simple telescopic antenna with 'First test' Desktop like this:

Airspy Mini + Spyverter set to Linear gain level 16 (using simple telescopic antenna): 

 

It looks like the RF noise 'Desktop' mound is gone, but I think it is because the antenna is simple, it is not picking up stations as good perhaps less sensitive? It is similar to Airspy Mini + Spyverter set to Linear gain level 2 or less.

But because my RTL-SDR HF dongle at full gain is not making this, then it could be assumed that it is something to do with the Airspy mini + Spyverter combination? or Long wire Unun Antenna? What next?

It seems that with the Airspy mini + Spyverter combination it is much more sensitive to RF noise from various things perhaps?

So what next?

Further tests:
- Testing outside far away from the house.
- Testing using laptop on battery power instead of AC power adapter.
- Testing using a antenna far away from house.
- Somehow shielding from RF the Airspy mini more? Or is the noise coming from USB computer?

Will update soon.