Call Search
     

New to Ham Radio?
My Profile

Community
Articles
Forums
News
Reviews
Friends Remembered
Strays
Survey Question

Operating
Contesting
DX Cluster Spots
Propagation

Resources
Calendar
Classifieds
Ham Exams
Ham Links
List Archives
News Articles
Product Reviews
QSL Managers

Site Info
eHam Help (FAQ)
Support the site
The eHam Team
Advertising Info
Vision Statement
About eHam.net

   Home   Help Search  
Pages: [1]   Go Down
  Print  
Author Topic: DVT-B sticks as a spectrum analyzer  (Read 5366 times)
K9AQ
Member

Posts: 55




Ignore
« on: January 18, 2013, 08:12:31 AM »

I am using a DVT-B with an upconverter as an SDR panadapter.  I see a real potential for using this also as a building block for a low-cost spectrum analyzer.  Has anyone done any experimentation with this?

Don
K9AQ
Logged
KA4POL
Member

Posts: 2125




Ignore
« Reply #1 on: January 18, 2013, 09:48:45 PM »

With the emphasis on low-cost you don't have to do much. It mainly depends upon the software you are using. I have been doing this with my QS1R so why should the stick not work.
Logged
ZENKI
Member

Posts: 990




Ignore
« Reply #2 on: January 19, 2013, 01:13:53 AM »

How much on screen dynamic range can you get?
What will be the minimum resolution bandwidth be?

SM5BSZ has already been using LINRAD with  these DVT_B tuners. Linrad has a nice mode called TX Test mode which is excellent for checking transmitters for splatter etc.
You might check SM5BSZ's web page he has lot of data there.


I am using a DVT-B with an upconverter as an SDR panadapter.  I see a real potential for using this also as a building block for a low-cost spectrum analyzer.  Has anyone done any experimentation with this?

Don
K9AQ
Logged
KN0CK
Member

Posts: 22




Ignore
« Reply #3 on: January 19, 2013, 05:24:36 AM »

Don / ZENKI,

You have a great idea, but unfortunately the DVB-T USB receivers only exhibit a dynamic range in the area of 45dB which makes it fine for casual tuning as a panoramic display, but not for making signal measurements.  The reason for the marginal dynamic range is that the original intent of the DVB-T sticks was for picking up strong digital TV and radio signals and it worked fine for that, along with that the 'stick' has 8-bit tuning making it limited by design, too.  At 45dB dynamic range, it just doesn't make a very good spectrum analyzer for looking at spurs and other RF phenomena.

But you can still use it as a companion to your setup for viewing your I.F. off ANY radio (provided you upconvert it to what the 'stick' tunes to) and that you use the appropriate software that gives you the best panoramic display properties.  And as you're probably already aware, the DVB-T stick is a pretty nice - again casual listening - SW and Ham Band HF/VHF/UHF receiver provided you use an upconverter for HF and leave the upconverter off for VHF/UHF coverage.

73 de Marty, KN0CK
« Last Edit: January 19, 2013, 05:31:26 AM by KN0CK » Logged
KA4POL
Member

Posts: 2125




Ignore
« Reply #4 on: January 19, 2013, 10:29:11 AM »

How much on screen dynamic range can you get?
What will be the minimum resolution bandwidth be?

a) 90 dB
b) maximum resolution 25 kHz across screen

I think you mean max and not min.
Logged
ZENKI
Member

Posts: 990




Ignore
« Reply #5 on: January 25, 2013, 04:11:54 AM »

All interesting information guys. It would still be useful as a general purpose bandscope for older radios. For the price it just show the potential of the design. The Funcube dongle
is another ground breaking product.

Who knows someone might package the device as a PSK IMD monitor along with a Android or Iphone app. It certainly has potential
Logged
WV4I
Member

Posts: 136




Ignore
« Reply #6 on: January 25, 2013, 05:55:05 AM »

Following the Jan 2013 QST article, I acquired a DVB-T from Ebay for about $30 shipped. I got it working on a Win 7 32 bit OS, using SDR# software. I don't know exact dynamic range etc., but have mainly tried it on FM BCB, AM Aircraft, and 2M FM. Compared to receivers designed for those bands, it has a fraction of the apparent sensitivity, S/N ratio, etc.. For the price however, can't beat it as an entry level SDR receiver. And as some have mentioned, as a simple pan adapter and/or looking at relatively strong signals, the price/value ratio again can't be beat.

You will need a good antenna at least attic, if not outside, to hear very much, for the CCR or apartment bound. A discone comes to mind.

Also running Softrock and SDR-IQ on HF. I think that by time getting up converters etc., to use DVB-T for HF, you'd be better off getting one of the Softrocks or some other SDR in $100 range. The SDR-IQ easily outperforms the Softrock, but it's also $500 new. Only money, hi.
« Last Edit: January 25, 2013, 05:57:35 AM by WV4I » Logged
Pages: [1]   Go Up
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.11 | SMF © 2006-2009, Simple Machines LLC Valid XHTML 1.0! Valid CSS!