The "Black Box"

Show off any of your RTL-SDR or cheap SDR related projects.
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hav0k
Posts: 3
Joined: Sun Feb 23, 2014 6:57 pm

The "Black Box"

Post by hav0k » Sun Feb 23, 2014 8:31 pm

Hello everyone.

I've been tinkering around with a DVB-T TV tuner dongle based on the RTL2832U. I've ordered it on E-Bay and it seems like some Chinese import, so I can't tell you the exact brand of it. Later I've hooked it up to a "Ham It Up" up-converter from Nooelec.
I was satisfied with the results, but wanted something more than a bunch of cables around my desk. Also there was quite a lot of noise that was being picked up. I've decided to put it in a box (and do it properly in the process).

The "Black Box" (as I call it).
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The box is whole made of aluminum. Had to drill some holes for the cables/controls. Also there are two pairs of rubber feet on the bottom to help with stability. The paint job is not perfect but still looks good for a homemade project.

Inside the "Black Box".
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The USB cable shield is terminated (open) at the device end. The whole box is connected to the GND terminal.
The RTL dongle lies on a top of a double-sided thermal adhesive patch that greatly helps with heat dissipation, also note the three heat skins I've glued on top of the chipset, tuner and the voltage regulator (using thermal-conducting epoxy). They were getting way too hot for my comfort.
Initially, the USB cable terminals were put through toroid ferrite rings, but I've noticed they only deteriorated the work of the unit - greatly messed up the USB communication to the device, so I removed them. The USB cable itself has two pairs of snap-on ferrite filters (outside the box).

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The 50 ohm BNC connector has the advantage of easy connect/disconnect, and suits perfectly to my antenna system (an external "discone" on my roof, fed through RG-213 cable). Initially, I wanted to make the USB cable detachable too, but wasn't able to find a suitable connector to mount on the box.

Overall this turned into a very sturdy unit. The box serving as a giant heat sink for the dongle assured lower frequency drift due to heating up. Also the noise has been significantly cut and distant low-signal stations are now much clearer to hear, this is especially useful on the HF band.


Please, tell me what you think. Or If you have any questions or suggestion I'll gladly hear them.

PS: Excuse me if my English is not on the level, it's not my native language.

Virtualan
Posts: 1
Joined: Sat Apr 12, 2014 2:23 pm

Re: The "Black Box"

Post by Virtualan » Sat Apr 12, 2014 2:29 pm

Good Stuff. It looks very similar to mine.

https://www.dropbox.com/sh/qj8ja8quri1ltlt/MQr5DwX0Oq

randy028
Posts: 1
Joined: Sun Jun 22, 2014 11:21 pm

Re: The "Black Box"

Post by randy028 » Sun Jun 22, 2014 11:28 pm

Where did you buy the aluminum box at?

hav0k
Posts: 3
Joined: Sun Feb 23, 2014 6:57 pm

Re: The "Black Box"

Post by hav0k » Tue Jun 24, 2014 6:03 pm

randy028 wrote:Where did you buy the aluminum box at?
A local store. But these boxes are fairly common and you should be able to find one at your local retailer. Eventually you can use any metal box retrofitted for the purpose or even build one from sheets of thin metal.

sabakanwal
Posts: 1
Joined: Tue Dec 16, 2014 11:22 am

Re: The "Black Box"

Post by sabakanwal » Tue Dec 16, 2014 11:31 am

I'm looking for a way to receive and view CCTV video. I've seen something on a russian website but I can't get anything to come in to confirm that its working. These devices were designed to be TV tuners, so you would think this would be easy.

rtlsdrblog
Site Admin
Posts: 2835
Joined: Mon Nov 19, 2012 11:54 pm

Re: The "Black Box"

Post by rtlsdrblog » Tue Dec 16, 2014 11:48 am

sabakanwal wrote:I'm looking for a way to receive and view CCTV video. I've seen something on a russian website but I can't get anything to come in to confirm that its working. These devices were designed to be TV tuners, so you would think this would be easy.
It all depends on what frequency the CCTV camera is transmitting on and what protocol it uses. If it's standard analog PAL or NTSC you can use TVSharp to get black and white images.

The dongles are designed for DVB-T TV, which is digital TV. If your CCTV is using DVB-T then you can use the TV drivers at http://bit.ly/1tZAriA and a program like ProgDVB to see this.

Also, in the future please start a new thread for an unrelated topic.

BeardieBob
Posts: 2
Joined: Fri Jan 02, 2015 12:41 am

Re: The "Black Box"

Post by BeardieBob » Fri Jan 02, 2015 12:58 am

Gidday hav0k,

Thanks for your post. I am at the thinking stage and your post gives me strength. I found Buccaneer brand USB bulkhead connectors at http://www.bulgin.co.uk/Products/Buccan ... r_USB.html (and many other sites).

You said, "I connected the box to the GND terminal." From the photo, I think this is the USB GND terminal. Is this correct? I have been puzzling on this point.

Thanks more. Really helpful.

BeardieBob

hav0k
Posts: 3
Joined: Sun Feb 23, 2014 6:57 pm

Re: The "Black Box"

Post by hav0k » Fri Jan 02, 2015 12:24 pm

BeardieBob wrote:Thanks for your post. I am at the thinking stage and your post gives me strength. I found Buccaneer brand USB bulkhead connectors at http://www.bulgin.co.uk/Products/Buccan ... r_USB.html (and many other sites).
These look good. Are you planning to put it in a metal box too? If you do, make sure the cable shield is not connected to the box. The box is "grounded" to USB GND.
BeardieBob wrote:You said, "I connected the box to the GND terminal." From the photo, I think this is the USB GND terminal. Is this correct? I have been puzzling on this point.
Yes, this is the USB GND terminal, not the cable shield. The shield itself is only connected to the computer via the USB plug (at the computer side) and not connected to the device in any way (open-end).

Good luck with your project. :)

BeardieBob
Posts: 2
Joined: Fri Jan 02, 2015 12:41 am

Re: The "Black Box"

Post by BeardieBob » Fri Jan 02, 2015 9:29 pm

hav0k,

Thanks for that. Definitely a box. All the arrows point to this as a way of minimising RFI. Some websites explain how to wrap adhesive copper tape around the dongle. The results look good but I worry about heat. My home has lots of hot weather. A box organizes things too. :)

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