Dongle

[shakysen]

Hi Boss wading thru the pile's of  stuff on The Dongle this site may serve  http://superkuh.com/rtlsdr.html

[dongle]

Hi Boss wading thru the pile's of  stuff on The Dongle this site may serve  http://superkuh.com/rtlsdr.html

There is some good stuff on there Sir.

I notice that they are saying that the more widely available tuner chip (R820T) can work on frequencies that the manufacturer does not document as being possible. If the gr-airmodes can initialise it and tune it in like it does the E4000 tuner, there will be no shortage of cheap dongles that can be used for ADS-B into the future when the E4000 ones run out.

[Anmer]

Dongle, what "dongle" hardware did you buy?

[IanH]

Mike - All the previous dongle stuff in is in OFF TOPIC section under the single thread "My new receiver".

In response to some of Dongle's comments:

For the ADS-B signal from the DVB-T stick, I chose to run Ubuntu under Virtualbox on a Win7 PC. I did note all the detail so I'll put that together in a document. It is unlikely to run on a Netbook though. My reception wasn't too good but that was likely to be an antenna problem. And since I have an SBS-1e, I haven't followed up since. Just proved it worked 

SDRSharp is very much a front end for radio reception. It gets updated frequently and I use it to listen to airband radio. So the latest version probably works a lot better than the version with the dongle. I agree that without a decoder it isn't intended for ADS-B. But you can feed ACARS audio into acarsd (http://www.acarsd.org/). If the scanner function is added it could poll through the frequencies.

Ian

[dongle]

Dongle, what "dongle" hardware did you buy?

I got one of these, but this guy has put his prices up a lot since then. He knows what he has got, I think and realises it has much more value as an SDR radio than it ever had as a TV dongle. It is the Newsky TV28T.



Mine came without an antenna but with some software on a home burned CD.

http://www.ebay.co.uk/itm/120994408433?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649

The same board is available in other dongles. There are American ones that are on sale for far less and some from HK for about £12

see lower section where International Sellers are offering items.


http://www.ebay.co.uk/sch/i.html?_nkw=E4000+%2B+Rtl2832u&_sacat=0&_odkw=E4000+%2B+Rtl2832&_osacat=0&_from=R40

ALWAYS CHECK THE CHIP LINE UP. (RTL2832U + E4000) No guarantees if other chips are used instead of those.

[Anmer]

Excellent, thanks Dongle.

[IanH]

Having bought from eBay seller "nooelec" (1st 4 items in your eBay list are from him), I would trust him to know what he was selling.

And just about to post what shaky just has.

Trouble is identifying what is on eBay from the list!

Ian

[Anmer]

I'll try Cosy Cove again tomorrow and failing that I'll get one from the eBay seller.

Then the fun begins. 

[dongle]

CosyCave has put his prices up a big amount, going by that last auction. On the other hand, he has soldered Electro Static Protection diodes into my dongle. They only cost pennies, and ought to be fitted at the factory, but weren't. You really do need them or your dongle might go very deaf all of a sudden during a hail storm when charged up specs of ice start hitting your antenna. Of course, if you made an antenna which is a DC short, such as a Slim Jim, or a J-pole, you wouldn't need to worry about that. Neither would you if you had a home made pre-amp in front of it, because that would take the hit if there was one and the transistor in the design I posted costs buttons.

Here is a neat antenna designing site for antennas that are a dead short for static.

http://www.m0ukd.com/Calculators/Slim_Jim/index.php


Ian -

Thanks for the info on using the dongle for ATC listening. I have an all modes tranceiver which can do this, but I had not realised there were better versions of the HDSDR software and perhaps drivers available for it. I did start off with Windows and HDSDR because I am not any sort of a Linux fan (only because I don't really know it well) but my impression was that it was awkward to use and there was a lot of distortion on it when I tried to use it for FM wideband programme listening. The quality was awful, actually, but this is not a hardware issue, only one of maybe drivers and the software which didn't really have the scope for Wide FM (ie broadcast station FM).

I will look about for an update.

[IanH]

SDRSharp is a Windows program. You have to install the Zadig drivers first which replace the standard Windows drivers for the DVB-T stick. Looks like you have the same one as me from CosyCave.

If you look at the downloads page on SDRSharp.com, the current Dev downloads are version 977. I was using version 838 at the beginning of the month! You also need to update the the pre-built Windows RTLSDR binaries and libraries from Osmocom (details here in SDR# section of http://rtlsdr.org/softwarewindows ) since that has been separated out but also is being updated.

For me, this provides sufficient ATC monitoring at a bargain price.

Ian

[dongle]

Thanks Ian.

That's very helpful. I'll have a go later and see what happens. It will be a touch awkward to try the stick down on VHF since it is now plumbed into the ADS-B antenna and pre-amp and is up in the loft. I have a ten meter USB cable coming down into my radio cupboard -a  sort of walk in small room about 5' by 5' on the landing. If the R820T tuner chips prove functional for this, I wills end for one. They are available on ebay for less than £7.

EDIT:

It looks from this link that not only can the R820 stick work with SDR Sharp, but also with gr_modes, so it should do ADS-B too. For something like £6.80 delivered from China, this would be a spectacular bargain!   

https://groups.google.com/forum/#!topic/ultra-cheap-sdr/KDcd40590ys

[dongle]

SDR Sharp problem

SORTED NOW - ignore

It was a net framework problem.

Got SDR sharp running and stable on the loft mounted dongle via the long usb cable.

I didn't change the antenna or pre-amp so I had limited listening potential, but I could hear weak two meter activity and the tower at the local airport. When I put the dongle onto 1090 mhz, as you would expect, I could see red streaks and lots of them either side of the centre frequency. There would seem to be some slight error in the frequency declared by the dongle. I'll make a note of it next time I run it. It seemed less down on VHF and a good bit more up on 1090mhz.

Thanks for the instructions Ian.

[dongle]

Found this interesting pile of information about gr-air-modes. Scroll down to the README file if interested. It seems that gr-air-modes will do a lot more than I expected.

https://github.com/bistromath/gr-air-modes

Well worth a look if anyone is interested in using the program with a dongle.

[IanH]

Things seems to be moving with gr-air-modes.

The final instruction in http://www.hamradioscience.com/the-rtl-2832u-sdr-and-ads-b/  no longer works:

uhd_modes.py -d –P

gives an error that it has been deprecated.

New command for new installations is:

modes_rx –d –P

For various reasons I tried two installations today. First one worked with this new command line, second one failed with an error I don't yet understand. Perhaps some code being changed behind the scenes? I'll try again tomorrow.

Ian

[dongle]

Well spotted there Ian. I wondered why I could see no reference to uhd_modes in the ReadMe file, but I saw the one you mentioned. I wonder if it works better in some way, and if so, how I should upgrade.

Vile weather here. Just had to pick up the wife from the hospital - her mother was taken ill today and she went in with her in the ambulance. It is snowing like crazy and the roads are an inch or more deep. Drove all the way there and back at 20 - 25 miles an hour.


I ordered a new dongle with the R820T tuner chip. Cost a touch less than £7 including postage from HK. Should take about three weeks or so. I'll play about with it on VHF connected to a new 300 ohm loop aerial I will make for Freeview and VHF. I have a good high location here so I can get away with bizarre aerials on Freeview. A vertical VHF loop will be broadband and will tolerate a lot of liberties while still performing. I'll connect to it with the dongle witha  4:1 balun to bring the impedance down to nearer 75 ohm. Just had a thought - if I make a uhf loop for the TV and connect it to a vhf one for the dongle and connect with a 2:1 balun to the pair of them, I'll be able to use the same downlead for monitoring air band and watching TV.  It'll cost pennies to try this. I've got enough wires going up the house for my other activities so if I can use one for two purposes, so much the better.