RetMar 16
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

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Show threadAsaril

@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]

Mar 16 at 6:21pmWeb
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