It would be awesome to have an SDR expansion card in the framework, for analyzing frequencies or also for penetration testing of wireless devices. I could also imagine it being handy for playing around with things like ZigBee. I am not so sure though if a sdr up to 2.5 GHz would fit into en expansion card. At least a subghz chip like the CP1101 would fit. It has gained recent popularity in the flipper zero which also uses it for subghz communication. You can use it to open tesla charging ports or garage doors.
I don’t have a framework yet, but i might consider designing a board like that.
This is a cool idea, although I might have concerns about the durability of something like an SMA antenna connector sticking out of a laptop like that. Still, as a ham radio guy, I won’t say “no” to more radios…
I have thought of this and happens to have a nesdr which is cheap and tiny. I am also really interested in CP1101 and may work on it after I get around another project.
I see no problem physically fitting it inside the expansion card form factor. In fact, I have just stuffed a wifi receiver in an expansion card. (if you are interested, it is based on ALFA Network AWUS036ACS. simply get rid of the original usb, solder a type-c connector, flood this with hot glue and it works. I also 3d printed a top cover and just plastic welded it on since there is no good reason for me to open this)
However, the potential consideration imo would be:
if the antenna is sticking out anyway, is it better to make it an expansion card or just leave it as a usb dongle? I did mine more or less for experimentation here
SDRs can get toasty hot. is it thermally practical to fit it in there and do you really want something that toasty under your laptop?
There are enough room inside the laptop besides the usbc ports for the expansion cards to put an AMC connector besides the usbc, and possibly enough room to fit another attanna in the screen.
So, assume there exist an RF connector that is small enought and not as fragile as AMC, is it possible to drill a hole in the bottom enclosure and add the ability to connect to an internal attanna from expansion cards? Thus eliminating the “attanna sticking out” issue?
Just curious, probably not going to try it out for the level of cursedness. (and my framework being my main laptop I depend on rn)
You might be able to just make an oversized expansion card, with a relatively flat antenna that hugs the side of the laptop. Still some chance of getting caught, but not as bad. Assuming your desired bands can function well enough with such an antenna.
I moved my site from a wiki platform over to Sphinx and in doing so missed moving this over. I don’t have time at the moment to update my site, so here’s the text. When I do have time I’ll repost with photos.
I love my Framework laptop. While there’s much to like about them, the fact it uses expansion cards is something I really appreciate. I’m also a software defined radio enthusiast. I hate having a clunky SDR hanging off my laptop.
Why can’t anyone make an SDR dongle built into a expansion card?
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Oh, that’s why. There’s no market for one. But that didn’t stop me.
I don’t own a 3D printer, nor do I have access to one. I also have no way to build PCBAs. So where’s what I did.
My intent was to cut the male USB A connector down to the bare minimum allowing everything to fit inside the expansion card housing. I practiced on an old thumb drive and all I did was destroy the connector. So I settled on letting the PCBA stick out slightly.
I gutted the expansion card, attached the USB adapter, placed the SDR inside the housing, glued it down, and voila.
About a week ago, me and a friend had the idea to put an RTL-SDR in an ExpressCard slot. I had some free time, and ended up getting as far as reverse engineering the schematic for the generic RTL SDRs. As I was finishing that, I started to think about making one to go in a framework module, and found this thread. Knowing that the NESDR Nano fits in the space was enough for me to download the expansion card template…
I’m not sure how it happened so quickly, but I now have a design for a RTL-SDR expansion card close to done.
Unfortunately, I wasn’t able to find the chips for sale, so building one will involve desoldering the chips from a preexisting SDR and putting them on the custom board. I don’t really have the equipment for that, but that’s a problem for later. This is also my first time designing a PCB, so don’t expect it to be perfect.
I’m still trying to figure out some details, but I’m planning on ordering some boards in a few days.
