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I got some RF equipment for free (it was going to the trash and I 'rescued' it). It's almost new, and seems expensive, but i don't know it's purpose. Googling the model numbers yields very little information :(

The equipment in question: https://imgur.com/a/AEIoKwz

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  • $\begingroup$ Looks like satellite TV distribution hardware for a building installation. Google for "diseqc satellite distribution". $\endgroup$ – Juancho Jun 11 '18 at 13:35
  • $\begingroup$ Pretty fancy. The right person will want the lot. $\endgroup$ – SDsolar Jun 21 '18 at 2:32
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TL;DR: Sat TV equipment, 75Ω, probably analog. Obsolete. If anything, keep smallest switch matrix.

It's commodity satellite TV equipment. Let's go through this:

  1. a Bias injector (hence the different voltages next to each port) and satellite dish control signal multiplexer (DiSEqC uses control signals at 22 kHz, for example) for satellite dish motors and LNBs; probably of not much use unless you want to control a satellite dish motor whilst receiving commercial satellite TV – there's very likely some filters in there that restrict the usefulness for other bands. But you can't know without testing.
  2. More interestingly, this is an antenna switch. Sat dish feeds often have two polarizations, and this seems to have been used for a system with linear (H=horizontal, V=vertical) polarization. But you can use that to switch anything – the polarization of the antenna doesn't change anything about the wave on the cable. Anyway, it won't be of help unless your signal happens to be in the upper or lower band (H=high, L=low), because the fact that this is printed on the device almost certainly means there's filtering to these bands inside. But again, you can't be sure, and would have to measure. Maybe it's really just a set of four switches with four positions each, and then this would be rather cool. Control of these probably happen through digital signals sent by the consumer set-top box (DiSEqC).
    The splitter is just a four-way splitter of unspecified power characteristics.
  3. see switch from 2. But larger.
  4. see 2.
  5. see 2.
  6. a set of amplifiers; the trimmers probably just set two different bias voltages of a RF transistor and a matching PIN diode or something. Doubtful it's very useful for anything but analog satellite TV. It's not going to be extremely Low-Noise (the LNA usually being part of the LNB right at the feed), nor high-output power (just being used to amplify enough to serve the longest cable in a residential complex).
  7. That's an obsolete 24-port 100 Mbit/s switch. The gigabit rating only applies to the two uplink ports. Dump it. A 20€ electronics store gigabit switch has more bandwidth, plus you pay for electricity.

Generally, sat TV equipment tends to use 75Ω impedance rather than 50Ω (which is what most signal processing equipment tends to use). So, at least at one point, you might have to match your system's impedance to these.

Regarding selling these off: If my suspicion is right, then everything about these, if it cares about frequencies and bandwidths at all, is optimized for analog Sat TV reception. That's obsolete, and I guess that's the reason these were tossed in the trash. Blind guess: You'll be able to sell these to someone who knows what they do, and needs specific parts from them. However, these people also have access to the internet, and can just order new components (and these UHF/VHF things at these powers and noise figures really only cost cents to dollars each, you pay for the integration in a good box and measurement/calibration); the prices you'll fetch will be modest. The highest potential profit I'd attest the switch matrices – the likelihood of these being useful for modern sat installations is highest, but then again, I haven't seen someone put up a set of dishes with multiple LNBs each in years. The age of large Sat TV installations might simply be over, with those wanting a large selection of high-def video opting for online services in middle Europe (which is where the power plugs suggest this equipment is from).

So, I'd inspect the switches to figure out whether I can control them without a sat-TV receiver (or by using a sat TV set top box, coupled only through a let's say 50 kHz RC low pass?), and whether they work well enough at the frequencies you want to operate. If that's the case, you have a set of 75Ω low-power switches, which is nice if you want to switch multiple antennas between multiple receivers. I wouldn't trust these to be bidirectional (measure!) nor to carry more than 1 W RF per port.

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This is a guess.

Looks like satellite reception stuff. Hook a few dishes on one side and then hook a few different receivers on the other side.

Looks like some of the outputs for the receivers are bandpass filtered. Looks like some of the outputs have different line levels.

I could imagine one or more satellite dishes could feed several receivers, each receiver listening to multiple channels.

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It looks like gear for distributing TV signals (satellite and otherwise, so it ranges from VHF up to microwave) around a building. Maybe some of it could be useful as coax switches or duplexers for amateur use, perhaps in a repeater site. Or put it all up for auction online and see what it fetches and what cool gear you can get with the result.

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