I find that my 1090 and 978 dongles (blue and orange ADSBExchange ones) get rather hot. As I write this, the blue one checks in at 113 degrees F and the orange one is at 108 degrees F. I’m preparing to place the system in my attic instead of inside the house proper, where temperatures will routinely hit over 110 degrees F.
Has anyone found a good heatsink for their USB sticks or are there other mitigations I should consider, or is the system using the USB sticks as a passive heatsink? I’m running a Pi 3B+ with heatsinks on the CPU and one other chip, in a plastic case. The Pi’s temperature is currently reading at 68.2 degrees C.
I’ve purchased an aluminum case with heat transfer columns and some thermal paste to supplement the transfer pads. Should be here in two days. Hopefully that helps. Reviews were favorable including a 15 degree C system temp drop in a recent review. Hopefully that will translate to cooler USB dongles and maybe some better reception?
RTL-SDR’s do run hot - it’s just the nature of the beast. Metal cased ones make it more noticable. I doubt that additional heatsinking will affect your reception much, but it’d be interesting to hear if it does. It shouldn’t hurt, of course, and might improve longevity.
I’ve been running the metal case for about 8 hours now, granted most of those 8 were when no planes were flying. So far, I’ve seen the following:
No noticeable change in range on 1090
978 has a slightly increased range, but that could be due to other factors
Wifi reception was greatly reduced.
I have noticed a roughly 15 degree C reduction in CPU temp. It has gone from between 68 degrees to 55 degrees. Since this will live in my attic, this is a very critical test.
I had been testing all of the changes in the same temporary location in one of the rooms at the end of my house. Unfortunately, due to the wifi issue I had to move the unit and antenna from its original spot to one about 10ft south where I could get a hardwired connection (the only USB wifi adapter that plugged in and started working was an old 802.11b adapter and the speeds were too slow for the system to be reliably accessed). This not only change the location, but also required the use of a different and taller mast. So I was left with multiple variables. I have a wifi extender that should be here today, so hopefully I’ll be able to put everything back to its original spot and continue testing. The final installation location will be in the attic, so I will need the wifi working.
I did put the 1090 saw filter on and have not seen any noticeable change there.
I do have hope for good 978 reception now, as the new temporary location is very close to where the antenna is now.
The metal case of the RTL is a heatsink, there is a thermal bonding material between the internal board and the case so it will get hot. While adding another heatsink to the case won’t hurt it is not needed is most situation.