Monday, December 28, 2009

LATEST SDR-RADIO TESTS PART 1 - PERSEUS

I have had some time after all to check a bit what is happening in the field of new software and receivers in the fascinating world of SDR-technology.

Finally tested a bit the latest release of Perseus software 2.1h. I was of course waiting for something from the big wish list which is easy to do but the implementation of the list is in the hand of the software designers. It is like waiting for presents from Santa Claus, you do not always get all you are dreaming of.

Well, the most important new features for me has been so far:

Multiple receivers attached to a single PC.

- for me not a big issue as I have currently not enaugh powerfull PC to run two Perseus at the same time. This feature is really good during DX-peditions. I wonder how many Perseus you can put into a same PC- they say you should not go more tahan totally 2000 kHz sample rate alltogether on one machine.

Waterfall Time Ticks

- this could be a usefull addition when checking what is happening on a certain SPAN especially hunting some carriers. However it seems SpecLab can do this more accurately and with many nice options.

Markers Log (file)

– this feature seems interesting, but of course not for a "normal" dx hunter, but for a more "scientivical" approarch what is happening on a certain SPAN. For instance when you try to find out certain fade in times of weak stations. However, the format is not a table if you log several markers (like a carrier and a noise marker) so you have to make some tricks with softwares (like Excel) to make graphs. Maybe someone could make a simple 3rd party software to do the graphs. As it seems the marker is locked into the peak of carrier, the lock can be loosed when the signal fades out ? And if you want to log markers before the fade in it seems hard as the marker is not locked to the exact frequency as far as I can understand. So making frequency locked logs of relative signal strengths one should use SpecLab instead. With SpecLab Plotterwindow you can trace the data of many carriers not only the signal level but the frequency drift as well.
The picture shows an example of a typical frequency with known offsets (Korea 1566.003 and Hubei China 1566.030).


Fully featured demonstration version

This version is nice to those who want to just test the software using some example files or files from friends. So now you do not need to have a Perseus RX plugged at least once to your hardware. This seems to be as a marketing tool for the Perseus. Money Talks.

WinUSB drivers and control DLL. Windows Vista and Windows 7 support.

Now the support of Vista 64bit and Win7 with own drivers, which is good. For me not a reality until I have to go for a new operating systems. I am still having a good worksing enviroment with an old XP. What I would like to see is a working system with Apple Macintosh OS or Linux environment!

Not all that good..

But what was a disappointment for me was that you still has to listen on AM or SAM when trying to read the exact carrier frequency! As you can see in an example here (AM-window behind the LSBdemod window) – a TA channel 1510 kHz, which also has very usual (and good indicators) of US stations: Boston, Denver and Seattle on 1510.018, 1510.000 and 1509.987 resp. (+- 1 Hz). If you look at the Perseus using lower sideband to avoid Euro QRM 1510 you are lost !

The same situation using the latest SpectraVue (now 3.03 with RBW 0.1Hz) – software shows using the LSB the carriers well and also automatically gives you the frequency reading on the upper left corner of the window. Maybe Perseus software could have one more button "show the center frequency of SPAN" which is independent of demodulation.


However, all in all the software runs OK and there are many good additions, it seems also there will be in a near future a version of Perseus software with easy connection over the internet. Let´s see. And last but not least: Perseus is the best receiver I have ever had. period.

3 comments:

  1. Tarmo!

    I fully support your thoughts and findings regarding the latest software from Nico. Particulary the discussion about showing center frequency when tuning lsb/usb.

    Running 2 Perseus at "full speed" with max sampling rate is not a problem for me at least. I even have the SDR-IQ running at the same time. And all this remote. The only snag is consumption of hard disc space...

    73
    Anders

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  2. OK Anders; what are the specs of your PC? They might be in your blog, but anyhow. Keep listening & comments are welcome, I hope to upload more about recent thoughts of SDRs.
    Just now "MORO" goes "well" (IQ+ALA100). 73 Tarmo

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  3. My Perseus PC:

    Pentium (R) Dual Core
    E5300 @ 2,60 GHz
    4,0 GB RAM

    73
    Anders

    ReplyDelete