[Skimmertalk] Red Pitaya set up with N6TV's instructions

[dd5xx at web.de]

Thanks for info Bob. I want to share my experience:

I used the aluminium case before and with the help of your script I monitored the temperature. I never exceeded 67° C even after long working periods (several hours!) and while running sdr_transceiver_hpsdr for the use of 6-band-CW-decode. I cannot explain why my RedPitaya was cooled down better than yours. One hour ago I did a test and replaced the aluminium case with the original RedPitaya plastic housing. Under this housing I installed a fan "SUNON MagLev DC5V ~0.55W". The fan sits exactly (!) above the FPGA heat sink, it fits perfect between FPGA heat sink and plastic housing. I want to emphasize, the cooling fan does not sit above/outside the plastic housing but directly on top of the FPGA heat sink. With this setup the maximum temperature achieved was 56° C. The temperature decreased about 10° C. I definitely will stay at this setup, the fan is doing a great job and I am quite happy.

Just wanted to share this information with you.

Best 73
Saki, DD5XX
 
 

Gesendet: Donnerstag, 05. Oktober 2017 um 02:56 Uhr
Von: "Bob Wilson, N6TV" <n6tv at arrl.net>
An: dd5xx at web.de, "SkimmerTalk Reflector" <skimmertalk at contesting.com>
Betreff: Re: [Skimmertalk] Red Pitaya set up with N6TV's instructions

For Alpine Linux running on the Red Pitaya, try this version of the temperature / voltage display script that I just uploaded (it was modified by Pavel Demin to work in the ash shell):
 
http://www.kkn.net/~n6tv/xadc-new.sh
 
According to the FPGA data sheet, 85° C. is the absolute maximum temperature supported by the FPGA.  Of course, heat is the enemy of all electronics (this is why so many un-cooled QS1Rs like mine eventually failed), so the cooler you can keep it, the better.
 
To cool the aluminum case, I simply mounted a 30mm 5V fan a few mm above the top center of the case, right above the center of the heat sink.  That required drilling and tapping some small mounting holes.
 
Since there is no room inside, and no cooling holes, it's about the only place to put it.  You can then carefully run two thin power wires into a gap on the left side of the case to bring them inside, then carefully solder or somehow connect those two wires to the power pins next to the Ethernet connector (the positive pin is closest to the center of the case).  This Red Pitaya is currently running 66° C with the ambient room temperature around 24° C.  
 
The Red Pitaya next to it in a plastic case with a similar fan on top is running 58° C.
 
When the room got very warm on a hot day (28° C.) I saw the temperature of the Red Pitay in the metal case get as high as 78° C., which was too close to the limit IMHO.  After adding the fan on top, the most I've seen is around 70° C.