SDR Heat Management

[silverninjastar]

I am an undergraduate student working on an outdoor spectrum observatory for a senior design project. Our expected set up is to place the SDR in an isolated box on a rooftop. We are planning to use the USRP N200. However, one of the issues we are expecting is the SDR's operating temperature. The operating temperature range of the board is 0-25°C. The environment this will be placed is commonly below freezing for 5-6 months out of the year. Does anyone have any ideas as to what would be a viable heating solution in order to keep the board within the operating temperature without emitting too much noise that would disrupt the data recorded by the SDR?

Edit: Although the SDR will create some heat, we are more concerned with the possibility of the system being shut off for some reason and being unable to restart once the temperature drops inside the container.

[aurgathor]

"The operating temperature range of the board is 0-25°C. "

Where did you get this information? That's very hard to believe since ambient temps can often exceed 25°C, and I see very little reason why a solid state SDR would have such a low upper temperature limit. It may become somewhat less accurate at higher temps, (or at lower temps) but I would expect it to work well above 25°C,

The flyer https://www.ettus.com/content/files/Ett ... r_HR_2.pdf does list 25°C, but looks to me that's the temperature where the specs were taken.

I've seen devices that had a heating resistor or two, but I think you just need to find the right sized enclosure and the correct amount of additional insulation, if some even needed, to ensure that your SDR stays above 0°C. As per spec, it can consume up to 7.8W, so you just need to ensure that it never loses power.

[silverninjastar]

We actually emailed Ettus in regards to the operating temperatures and they confirmed the 0-25°C range. They also mentioned that the SDR is capable of running below 0°C, but that it is possible it will not start up again below it. Even if the SDR does not need extra heat while operating, we are still concerned about if it were to be turned off by whatever means. Although, as I continue to think about it, if the SDR does not need more heat to run unless it is turned off, I feel it would it be simple enough to implement a heating resistor that only operates when the SDR loses power.

[Typhoon_MkII]

Okay, now I'm in a pinch, but in the other way around.
The fact is that I was planning to buy this house... in Corfu.
And because of that, I now have a SDR heat management issue as well, but about overheating this time. What can I do to protect my hardware from the merciless sun of the Mediterranean? I know it's supposed to work "well above" 25 degrees Celsius, but what does that mean? 28? 35? 50 degrees?

[rtlsdrblog]

Okay, now I'm in a pinch, but in the other way around.
The fact is that I was planning to buy this house... in Greece.
And because of that, I now have a SDR heat management issue as well, but about overheating this time. What can I do to protect my hardware from the merciless sun of the Mediterranean? I know it's supposed to work "well above" 25 degrees Celsius, but what does that mean? 28? 35? 50 degrees?

In very hot environments, air flow over the metal enclosure is really all you need. And ideally keeping it out of the direct sun.

[Typhoon_MkII]

In very hot environments, air flow over the metal enclosure is really all you need. And ideally keeping it out of the direct sun.

Okay, thanks a lot! It's fortunately simpler than I thought.

[nizz -freq scan noob]

I am an undergraduate student working on an outdoor spectrum observatory for a senior design project. Our expected set up is to place the SDR in an isolated box on a rooftop. We are planning to use the USRP N200. However, one of the issues we are expecting is the SDR's operating temperature. The operating temperature range of the board is 0-25°C. The environment this will be placed is commonly below freezing for 5-6 months out of the year. Does anyone have any ideas as to what would be a viable heating solution in order to keep the board within the operating temperature without emitting too much noise that would disrupt the data recorded by the SDR?

Edit: Although the SDR will create some heat, we are more concerned with the possibility of the system being shut off for some reason and being unable to restart once the temperature drops inside the container.

Hi!
First thing that comes to me is USB heat pad.
If DIY projects are not strange to you, then this will not be problem to build.
There are a lot cheap heating pads selling on ebay, ali...
https://www.ebay.co.uk/sch/i.html?_nkw= ... ad&_sop=12
Just put heating pad below enclosure with SDR.
I dont know how much noise create this type of heaters, if much, some type of metal barrier between SDR and heater maybe would be enough.
More advanced Use of temperature control switch module that will turn on heater when temperature is below desired temperature(in your case 0°C), and shut off heater when temperature rises above desired temperature(this could be set on +10°C, becouse SDR generatres his own heat, to prevent overheating).
Something like this https://www.ebay.co.uk/itm/50-110-C-W12 ... SwAetdLIdV
Basicly, this in only an idea for your problem, tehnical and practical thinghs with this solution can be adjusted to your needs
Hope this will help you

Denis

[Username]

the sdr must be heaten evenly or you it drift like crazy!
Mine run indoor in the Winter on the Attic without any heating fine.

[bmh]

Even more so than temperature you should also consider the possibility of condensation. There must be adequate ventilation in a heated environment to prevent moisture from building up and damaging the components. Rather than only applying heat when it gets cold a climate controlled system that maintains a consistent temperature regardless of the environment and is also capable of removing moisture is probably the best.