RTL-SDR & Raspberry Pi 5

[Omega-TI]

With the new << Raspberry Pi 5 >> coming out in October with all it's improvements, I wonder how many people will make a dedicated RTL-SDR platform around it.

It seems like an impressive little computer...

 

[a417]

Not a fan of the RasPi's anymore, likely bought my last one with the Zero 2 W. They've been trading on the name for too long, they have been passed by other vendors making equivalent systems for less with better specs and less reliance on Broadcom parts. Whilst the pop culture regarding raspi's has captivated many, the availability issues they've had for far too long and the availability of equivalents has made it "the cool choice" not the best choice.

 

[vagrant]

My RTL-SDR’s are doing fine 24/7 in a Pi 2 & 3, plus they handle other tasks simultaneously. I don’t own a Pi 4. As previously noted, if I need another SBC there are alternatives to explore as well as low cost used Windows mini PC’s like an HP I purchased.

 

[a417]

My RTL-SDR’s are doing fine 24/7 in a Pi 2 & 3, plus they handle other tasks simultaneously. I don’t own a Pi 4. As previously noted, if I need another SBC there are alternatives to explore as well as low cost used Windows mini PC’s like an HP I purchased.

They're good, but they're not great. The mini PCs and the other clones out there wipe the floor with them.

 

[wgbecks]

They're good, but they're not great. The mini PCs and the other clones out there wipe the floor with them.

Exactly! I quit using the Pi's when they became scarce during COVID and all of the price gouging started. I've since moved
onto surplus Small Form Factor (SFF) PC's that flood the market, are very inexpensive, and way more powerful in addition
to being virtually self-contained.

 

[Omega-TI]

Not a fan of the RasPi's anymore, likely bought my last one with the Zero 2 W. They've been trading on the name for too long, they have been passed by other vendors making equivalent systems for less with better specs and less reliance on Broadcom parts. Whilst the pop culture regarding raspi's has captivated many, the availability issues they've had for far too long and the availability of equivalents has made it "the cool choice" not the best choice.

I'll take your word on that as I don't really keep up on these things like I used to. I will say though that I'm less than impressed with my RPi4B+ with 8 Gigs of RAM running KODI because it does not play my 4K dashcam video very well, all the video seems to run in slow motion, which is probably due to it's only being able to run it at 30fps.

 

[a417]

Exactly! I quit using the Pi's when they became scarce during COVID and all of the price gouging started. I've since moved
onto surplus Small Form Factor (SFF) PC's that flood the market, are very inexpensive, and way more powerful in addition
to being virtually self-contained.

What really kicked them around in the dirt for me was the issue that they had with chokepoints & bandwidth limitations. So many of the bloggers and so-called 'techies' pressed them into service doing things that they weren't just meant to do.

It came into life as a proto board, it's still a proto board.

In 2014(ish) when the 2B came out, people said "zOMG I can MAEk THis INTO a NaS!", and they did...and then the bloggers hit it, and then it rended it...and homegamers and tag-a-longs were making them into NASs, and they started saying "wait...why am I only getting sustained +- 2.0mb/sec writes on my NAS? It takes forevvurr to save my 4 gig hentai mp4s", etc. Sure it's a great device, but it has YUGE disadvantages in the way that (if i remember correctly, it's been nearly a decade now) the networking device was on the same USB host as the exposed ports...so you can only imagine what would happen when the USB wifi adapter and the external USB device were trying to process a huge data transfer. Yep, fell flat on its face. The same thing happened when people said "oh I can make this a smart camera to watch Mr Piddles sleep in his doggie bed, when I'm off at the coffee shop working on my screenplay"...and then were shocked to discover that the high spec USB camera they attached was limited to like 320x240 @ 3 fps with MASSIVE latency. Decent for one camera if you're monitoring flowers, abysmal for anything more than one/or anything with a +2 FPS requirement. Nearly every person's post-mortem of those projects shared the same realization. It's "great for prototyping, but to do what I want will need more powerful hardware." Meanwhile, all that demand and the trending destroyed the supply chain for them and drove prices up to unreasonable levels (IMHO).

It can do these things, but more for proof of concept, not for any real production element. It's still a protoboard to me, no matter how much lipstick they want to slather on it. I've got one of the first 1B+s, a 2B, a couple of 3B+s and a handful of Zero 2 Ws - and they are all entrenched in a firmly static environment. One's a RTOS smart thermometer, one shows a google calendar on a TV, another controls outdoor lighting, and another makes my garage doors, heaters and lights "smart" thru a microcontroller...but none of them do any sort of heavy lifting, much less streaming anything. Not a single one of them employs a GUI, the one that displays a calendar doesn't even have a DE on it - it literally runs chromium direct to X. The refresh time is measured with a calendar. They just aren't cut out for that.

Personally, I can't imagine a situation where I would need one of them to run SDR in any capacity. Perfect example, I have an RTL_TCP instance running on a Linksys wifi router. Yes, a raspi could do that for me - but the linksys is already where I need it, has a wired connection home, and has an unused USB port.

 

[Omega-TI]

My 4B+ does fairly well running 1080p videos from an 8TB hard drive in the bedroom with KODI, but that is as much exercise I give it.

 

[vagrant]

I forgot about the RAM/memory leak issue as well as the lack of an RTC - real time clock. The latter can be fixed with an add on, but the memory leak means the device needs rebooting daily. A cron job handles it and another needs it once a month. Other Pi’s running different things needed it every two weeks and I took those offline. Still, it was fun using Unix again. It had been a decade since I used it and it surprised me I still knew commands and syntax.

Pi’s are like a paper airplane, for fun, but nothing serious.

 

[Dirk_SDR]

There are very many SFF PCs on the market.
Anyone who has a recommendation for a good one for SDR (at least 1 USB-A 2.0, Windows 10 [not 11!], Linux compatible, enough power for typical SDR applications, low EMI, ...).

 

[vagrant]

@Dirk_SDR - I use an HP EliteDesk 800 G2 mini with an SDRplay RSP2. No problem with viewing 10 MHz of bandwidth while it runs a NAS and other stuff simultaneously using Windows 10. Unsure about Linux and if any driver issues. Oh…these are inexpensive now and while not as small as an SBC, I have zero issues.

 

[HankFrank]

I have been using celeron-based MiniPCs from BeeLink with good success. They go on sale or have coupons on Amazon most of the time and you can usually get a 4 core Alder Lake with 8GB of Ram for well under $150 USD. Not sure about prices in Europe.

I throw Ubuntu on them and they work with Spyserver and other SDR-based programs just fine. No noise that I have detected in the shack, and I'm pretty fussy about noise.

 

[ErikSwan]

Not a fan of the RasPi's anymore, likely bought my last one with the Zero 2 W. They've been trading on the name for too long, they have been passed by other vendors making equivalent systems for less with better specs and less reliance on Broadcom parts. Whilst the pop culture regarding raspi's has captivated many, the availability issues they've had for far too long and the availability of equivalents has made it "the cool choice" not the best choice.

They're good, but they're not great. The mini PCs and the other clones out there wipe the floor with them.

Exactly! I quit using the Pi's when they became scarce during COVID and all of the price gouging started. I've since moved
onto surplus Small Form Factor (SFF) PC's that flood the market, are very inexpensive, and way more powerful in addition
to being virtually self-contained.

What alternative SBCs do you guys usually use/look at that are better than RPi? And where do you usually go to buy SFF/mini PCs? eBay?

 

[a417]

What alternative SBCs do you guys usually use/look at that are better than RPi? And where do you usually go to buy SFF/mini PCs? eBay?

For this type of stuff? eBay. I've also had luck at our town's bargain barn or the ewaste transfer center. If I was buying stuff for anything beyond my workshop, I'd go to a hardware recycler or reseller, one that deals with trade-ins and the like. Slightly more expensive, but less risk.

In terms of what hardware do I look at? I've got almost no restrictions, I usually look for the number & type of specific connections first (do I need USB ports? do i need multiple HDMI?) and then I go by price. I'm cheap, but I am experienced enough to be able to run just what I need on bare metal hardware and don't waste my time with things like a DE or a GUI. This makes a huge reduction in the computational power necessary, which means less CPU requirements, smaller memory footprint and less heat. Most of it ends up headless, so I don't need a desktop environment and a display manager if I was just serving up rtl_tcp for another computer to access remotely. This enables me to not waste something like a raspi 3b or greater, when the task can be done by the workshop wifi device running Tomato. It's sitting there providing 5g to the basement, so why not use that USB port on the back for the RTL hardware and convenient access to the big antenna wiring?

If you're decidedly not as saavy as some, and you need that Windows gui fallback to keep you in your comfort zone...a big branded SFF is probably your safest bet, they pop up all over for very cheap.

 

[iowajm780]

@Dirk_SDR - I use an HP EliteDesk 800 G2 mini with an SDRplay RSP2. No problem with viewing 10 MHz of bandwidth while it runs a NAS and other stuff simultaneously using Windows 10. Unsure about Linux and if any driver issues. Oh…these are inexpensive now and while not as small as an SBC, I have zero issues.

Same setup here. I purchased it to help with the power bill since I was running a full size tower i7, 500 watt power supply. With the AC running all summer this helped by only using about 35 watts. It is running SDR Trunk and a bunch of other software all at once. Only being a i5 with 16gb ram, it never misses a beat. Going to add an SSD at some point for more storage than the 500gb M.2 drive it came with. I was hoping to add another fan on the exterior but there is really no vents. I can feel the heat from the rear fan and I am thinking of putting a larger fan behind it to suck that heat away quicker. Tempting to get another one for a spare ready to go. The price was right so getting another one is likely.

 

[a417]

Same setup here. I purchased it to help with the power bill since I was running a full size tower i7, 500 watt power supply. With the AC running all summer this helped by only using about 35 watts. It is running SDR Trunk and a bunch of other software all at once. Only being a i5 with 16gb ram, it never misses a beat. Going to add an SSD at some point for more storage than the 500gb M.2 drive it came with. I was hoping to add another fan on the exterior but there is really no vents. I can feel the heat from the rear fan and I am thinking of putting a larger fan behind it to suck that heat away quicker. Tempting to get another one for a spare ready to go. The price was right so getting another one is likely.

It will entirely depend on your physical location for this device, but if I feel the system is not getting enough cooling and I'm not considering aesthetics... I've used a 3-inch hole saw and punched a hole in a case before and then put a large fan on the outside of the case (with a finger guard) and allowed that fan to supplement whatever was built into the system. It's not pretty but it moves a ton of air.

Looks kind of goofy with a large fan outside the case, but i couldn't give 2.375 s**ts about how it looks on the shelf in the workshop if it keeps temps and hardware stable.