2014/06/22

My newest antenna: Eggbeater II for 70cm ham radio satellite band

Hi,

after visiting our local bulding center yesterday, I assembled the Eggbeater II antenna today.

Have a look at:

Click to enlarge
It's the 70cm version for ham radio satellites. I followed the tutorial written by ZR6AIC, Anton. You can find his tut here: http://zr6aic.blogspot.de/2013/03/building-my-eggbeater-ii-omni-leo.html

Click to enlarge. Red dots == doppler of satellites
As you can see there a few strong signals. I feel that this antenna is the best one I ever build for 70cm satellites. But let me check this out the upcomming days...

I just made a short movie that shows the performance of the antenna:


2014/06/18

"Yes sir, there are a lot of them in outter space."

Hi,

since a few days I'm tracking the 70cm ham sat band from 435 to 438 MHz. An yes: they're still alive. :)


Every red dot marks a doppler of a satellite.

Click to enlarge.

Now I've to identify the calls of the satellites.

2014/06/15

Found a few pictures of airplane and garves radar doppler - a short movie

Hi,

I found a few pictures of airplane and garves radar doppler I did with HDSDR, speclab and rtlsdr on my old harddisk . I made a short movie out of a bunch of jpegs.

Have a look at:


This movie shows doppler of airplanes on AM atis transmitters or meteors reflected by graves radar france. Don't look at the box in the left corner. It has wrong frequency values and many typos. 




2013/12/15

Doppler experiments

Hi,

inspired by OM DJ0MY (thanks!) I tried to get some nice doppler signals. I tuned to Graves radar on 143.050 MHz and Hamburg ATIS on 123.125 MHz.

With my "new" diy lindenblaad type antenna (new == 1,5 years old ;) ) for 70cm I caught a few nice doppler signals.



Let's go :) .



Doppler by planes on Hamburg ATIS frequency. The transmitter should be about 120km away.


Frequency drift of RTLSDR, maybe.

Distance between QTH and Hamburg ATIS transmitter.


Doppler by ISS on Graves radar frequency 143.050MHz. See pulse/pulse break on ISS. ISS was about 1000km away - or more...


Pulse break from Graves radar on ISS.

Pulse length from Graves radar on ISS.




2013/12/10

Latest wx ballon heatmap

Hi,

last night I did a new heatmap with RTL_POWER. The frequency range is 404MHz to 406MHz. Intervall 30 seconds and binsize is 2000Hz.

I wanted to know which wx balloon signals are available at my place.

This is the result of 13,5 hours recording.


I caught seven balloons on five different frequencies in wx balloon band. Next time I will try to decode them with Sondemonitor by COAA.


2013/12/01

Reflections of Graves radar, Dijon, France

Hi.

Yesterday a well known OM told me about Graves radar located near Dijon in Framce. It's waves are transmitted on 143.050 MHz.

If you tune your rx on this frequency and watch the FFT with HDSDR for e.g. you can see reflections of these waves on objects that are flying in the air above.

There objects could be planes, asteroids, meteroids, ISS and other things in heaven above.

Have a look at this video, please. You can see a few of these reflections. Some a small, some are bigger. The duration of the recording is about 34 minutes.


The distance between my ocation and the Graves radar is about 680km. 



2013/11/23

HOPE OSCAR 68

Hi all.

tonight I caught the telemetry beacon of ham radio satellite HO 68.

HO-68 telemetry cw signal. Analysed with SA free. Click to enlarge.


My setup:

RTLSDR
TV satellite amplifier 40-2400MHz
Seven element yagi antenna for 70cm band, 30° elevation, about 160° azimut, under roof
HDSDR

I'm waiting for more amateur satellite signals to come...




2013/11/16

RTLSDR: rtl_power - another example

Hello,

yesterday I used rtl_power to create another heatmap. It covers the frequency range from 3 MHz to 5 Mhz.

Have a look at here, please:

http://www.qth.at/de8msh/bilder/heatmaps/hf.png

ATTENTION: this picture has a size of 17 MB! :)

As you can see there are many stations that come an go again. Ham radio stations, BC stations, Stanag 4285 and many more...




2013/11/14

RTLSDR: rtl_power

Hi.

There's a new utility in the famous RTLSDR package: rtl_power. Coder keenerd says about it:

Rtl_power is a small CLI tool for logging wide swaths of bandwidth. You can specify any chunk of spectrum, with any FFT bin size and any logging rate. (For sane values of any.)


Read more at reddit:


http://www.reddit.com/r/RTLSDR/comments/1kpf3m/new_utility_rtl_power/

I've done a hf scan with rtl_power lately. It shows a spectrum graphic from 3MHz to about 15MHz.

You can see it here:

http://picpaste.de/pics/hf_3M_15M_2.1384457866.jpg

Attention: it's a big picture! ;)

You can see many bc stations that come and go. OTHR are visible, too. And many other stations.

My setup was a DVB-Tstick modified as direct sampler. I connected my 12m wire to it.

It's a very cheat solution for non realtime / longterm hf band observations. But you can also use it with a unmodified DVB-T stick, too.

And now have some fun with rtl_power :)

2013/09/27

PA0RDT antenna on soundcard

Since yesterday I'm using my good ole PA0RDT antenna again. I connected it directly to the soundcard of my "radio pc". On this pc there is Speclab/DL4YHF running.

The soundcard is a simple 48kHz range type. So a samplerate of 24kHz is possible. That means that Speclab can sample from 0 to 24kHz, too.

Here's the result:


PA0RDT. PC. Soundcard. Speclab.
It's kind of fun to do VLF with a tiny setup like that. Needless to say that a 96kHz of 192kHz soundcard would be more fun ;) .