Ret
See TONS of these on AliExpress... What exactly are they? They definitely smell of "anti-drone jammer" type things to me... https://www.aliexpress.com/item/1005010359595614.html
30 W Ldmos-Zirkulator Lora GAN HF-Modul 400–470 MHz 800–900 MHz 1,2 GHz 1,5 GHz 2,1 GHz 2,4 GHz 2,6 GHz 5,2 GHz 5,8 GHz - AliExpress 502

Smarter Shopping, Better Living! Aliexpress.com

aliexpress.
Mar 16 at 5:39pmWeb
Show threadOfficeplantMar 16
@ret yes and mildly funny that amazon ones are listed as safety and diagnostic equipment
Show threadl_b_iMar 16
@ret Based on the image, LoRa is a long range RF protocol. GaN is a high power transistor used in RF applications. It might be something as simple as a high power RF front end. Though LoRa in this case might not be the protocol and just be "long range" as in high power.
Show threadRetMar 16
@l_b_i I thought that, but if you look there's no "in" port so it can't just be an amplifier. There's also not enough in there in terms of micros, RF frontends, etc for it to have much "smarts" in it. I'm 95% sure they are just jammers.
Show threadl_b_iMar 16
@ret RF I thought front ends don't usually have smarts, just power and frequency management. A jammer would also need some smarts that are not present. If it were just blasting out noise you wouldn't need to worry about any return path, but it looks like there is one there.
Show threadArikMar 16
@ret I get a 404 when I try to view it with a Netherlands country setting. Setting it to UK works.
Show threadRetMar 16
@pq1r I wonder if they know some countries have more intelligent/thorough customs checks...
Show threadAsarilMar 16

@ret the keyword probably is circulator. It's a device with three equal ports, that forwards RF signals only to one of the neighboring ports, around the circle.
A signal going in port A comes out on B, going into B out of C, and into C comes out in A.

Can be used to join a receiver, transmitter, and antenna, so that the signal from the transmitter goes to the antenna only, the signal from the antenna goes to the receiver only (and the receiver doesn't output a signal, so nothing goes into the transmitter).
Nothing smart inside there, apart from the genius engineering itself. It doesn't produce a signal in itself, and is not particularly "dangerous" to import.

[Based on the pic in the thread, link also doesn't work for me]

Show threadRetMar 16
@asaril I think these contain a circulator. But there’s definitely more to it than that. The circulator is the small square thing up top.
Show threadAsarilMar 16

@ret ah. Yeah, that looks like a lot more  

If the labeling is correct, it would probably be an amplifier then (PA = power amplifier, the last stage in a transmitter). And GaN could then be the material of the power transistor, suitable for high power in RF

Show threadAsarilMar 16
@ret maybe the circulator then is used as a safety against reflected power, if no antenna is attached or it is mismatched. Or the block next to it could be a connector on the other side, which would then lead to a receiver?
Show threadAsarilMar 16
@ret the lower half though, seems like it could generate something on its own. The input wires don't look suitable for an RF input for just being an amplifier (unless one of then is a coax, hard to see), and the part in the left side could be some oscillator?
Show threadAsarilMar 16
@ret searching for the text, some of the other modules I found the wires listed as being Vcc, Gnd, and "enable", and the device itself as being a CW transmitter. So it probably is just that, a bit of power management, oscillator, amplifier. If the enable is fast enough, it could maybe be used as a CW/OOK transmitter. But I wouldn't be surprised if it just takes a while to get to steady state, so maybe not so useful outside its suggested main use
Show threadpolprog68kMar 16
@ret @asaril That looks like a PA with a circulator attached to it, the question is what drives the PA. I dont see anything obvious