SatNOGS performance and cooling on RPi4

Hi all,

I finally got RPi4 4GB model for my station upgrade. Can anyone share their experiences with Satnogs and RPi4 performance-wise? Also what do you use for cooling since the RPi4 produces significantly more heat.

Thanks!

1 Like

I can’t see any performance issues on my pi4.
I use a plastic case (bad for cooling) and have placed small cheap heat sinks like these on the usb controller and the cpu. The pi is placed in the attic.

2 Likes

This is my Satnogs node (311) setup: RPI4 / 4G. No issues abt temperature and performance.
It’s housed in a plastic enclosure, right near the antennas, in external position.
EuhDCODXYAUHM3d
At the moment the LNA it’s missing cause maintenance, but there’s a 16 Gb USB dongle to record IQ.raw data ( I’ll write soon a post describing my solution abt recording )
Enjoy!
I3VFJ, Vittorio

3 Likes

I have had very bad experiences with Raspberry Pi 4 units and RF noise. Placing one near an antenna is a recipe for a high noise floor.

Have you done any testing of signals from the SDR with and without the Raspberry Pi 4 powered? Of course this would require a separate laptop to hook up the RTLSDR.

I’ve had a look through your observations, and for your setup I’m not seeing the SNRs I would normally expect from a turnstile station. You have adjusted your waterfall colour scales to make the plots ‘look good’ but this doesn’t mean that the observations are actually useful.

1 Like

Yes, I agree but actually it isn’t so close (abt 8m, 2m from the mast base). Moreover it’s mandatory to use ferrite clamps, adopt a linear PSU, and switchoff the HDMI into RPI.
In the past the LTE router was in the same enclosure, making a lot of wb noise: moved in separate enclosure abt 20m away ( actually on the other side of the house, completely out of sight from the antenna) resolved the issue, checked as per your suggestion with a separate system.
Abt the SNR, as told, at the momento there isn’t any LNA, only RTL dongle; I agree that now the system is useful only as “go / no go” … This node it’s abt 40 km far from my home, so replacing & maintenance isn’t easy :slight_smile:
I’m managing to switch from wb LNA to tuned amplifier, working in progress!
Also I’ve adjusted the waterfall dynamic range for two reasons: first to have the same scale over all the observations, next to “look better”, highlighing sats signals.
Looking at past observation I had nice SNR and good decoding from some sats ( Spooqy was the best, if I recall right).
Well, you know, testing / trying it’s the beauty of our activity, isn’t it?

I3VFJ, Vittorio

2 Likes

Hi all,

Thanks a bunch for your replies, very good stuff. Also looking forward for @i3vfj post describing more details of his setup!

I decided I will add a small fan to my RPi4 so it doesn’t get throttled.

Thanks!

1 Like

In my experience with all the rpi’s from old to new, the 4 is very prone to overheating and not behaving properly despite thermal throttling. Either add a small heatsink and a fan, or go for the heatsink cases that covers the entire motherboard.

Yeah, I noticed that so I ordered a full heatsink case and I’ll also add Noctua fan to it for good measure.