There are only 2 main switches that work with most, if not all, FTA receivers and regular (legacy) LNBs:
22 kHz switch, connect 2 LNBs to a receiver
DiSEqC 4×1 switch, connect up to 4 LNBs to one receiver.
22khz switches, these are really simple, they look like a splitter but they are a simple on or off switch, 0khz and 22khz are the 2 input ports and then one to the receiver port, when you have 22khz off on your receiver , the 0khz port is connected, when you have 22khz ON on your receiver, the 22khz port is connected.
This switch is used to connect 2 LNBs to a receiver.
The 22 kHz switch has the big brother, it is a 22 kHz DTV or 4×4 switch, this switch has 4 inputs to connect 2 DUAL LNBs and can be connected to up to 4 receivers.
2 inputs are labeled 13v, 0khz and 18v, 0khz (remember the internal switch of the LNBF), and the other 2 inputs are 13v, 22khz and 18v, 22khz. This allows both polarities of each LNB to be inside the switch at all times, so any of the 4 receivers can access any polarity on any of the 2 LNBs.
These switches also come in 4×8 format for up to 8 receiver connections to 2 satellites.
DiSEqC is a pulse switch, it also uses a 22khz signal but uses a one-time pulse to set the DiSEq switch to 1 of 4 ports, these switches come in 2×1 and 4×1 models, for 2 LNB to ONE receiver or 4 LNB to ONE receiver, respectively, these can NOT be used for more than one receiver, you must use another DiSEq switch for the second receiver.
DiSEqC-1 or 2 or 3 or 4 in your menu will cause the DiSEqC switch to switch to that numbered port, some receivers use A, B, C, D instead of 1, 2, 3, 4.
This “pulse” is only sent once, if the DiSEq switch is too far from the receiver you may lose it and not switch ports, sometimes switching between channels can make the switch happen, the pulse repeats every time you switch between channel, but moving the switch closer to the receiver can improve its performance.
DiSEqC = Digital Satellite Equipment Control, this was designed for FTA receivers.
DiSEqC switches come in 2 main types, Committed (1.0) and Uncommitted (1.1), but also Committed 2-way (2.0) and Uncommitted 2-way (2.1).
The compromised switches (1.0) are the most common and are the ones that come with the receivers.
These switches require the FACTORY software in your FTA to operate properly, 1.0 means your receiver can operate compromised switches ONLY, 1.1 means it can operate compromised and uncommitted switches, 1.2 means it can operate compromised and uncommitted motor controls plus DiSEqC.
2.0 is the same as above, 2.0, 2.1, 2.2 but the receiver can also receive information from the switch, 2.0 switches receive the pulse command from the receiver, then switch port, then send a confirmation to the receiver, if a El Receiver 2.0 does not receive confirmation, it will send the DiSEqC pulse over and over again until the switch confirms that it is on the correct port.
Putting 2 DiSEqC Compromised switches on a wire is a no-no, that’s why there are Compromised and Non-Compromised switch types, a compromised switch is placed first on the line (the DiSEqC pulse comes from the receiver so the former would be closer from the receiver), then you can connect an unconfirmed switch to the committed switch, the compromised switch will ignore commands from the unconfirmed switches.
Compromised 4×1 switches cost around $ 20, uncommitted 4×1 switches cost around $ 80, so unless you have to have 16 LNBs connected to a receiver with compromised switches.
No multi-receiver DiSEq switches for legacy (regular) style LNBs
22 kHz switches and DiSEq switches can work well together, with one restriction, the 22 kHz switch must come AFTER the DiSEq switch.
So you can connect a 22 kHz switch to two LNBs and then connect the output of the 22 kHz switch to port 1 of the DiSEq switch. So instead of 4 LNBs you could have 5 LNBs connected, you can add a 22kHz switch to each DiSEqC port for a total of 8 LNBs connected to one receiver.
Dishnet Legacy switches are designated by SW, such as sw21 or sw64, they do not use true DiSEqC pulses, so they do not work with FTA receivers.
Legacy TWIN and QUAD LNBs have built-in SW switches, so they won’t work with FTA receivers either
DishPro TWINs or QUAD LNBs have an internal DiSEqC switch, so EACH port on the LNB has access to any of the 2 internal LNBs, 110 or 119, DiSEqC 1 = 119 and DiSEqC 2 = 110, these LNBs require a channel list DP.
DishPro external switches, there are now 2, a DP34 and a DPP44, both use true DiSEqC pulses, so they will work with FTA receivers, but you must use DP LNBs to take advantage of the multi-receiver aspect of this switch.
(The DPPlus LNB DOES NOT work with FTA receivers, it does not use true DiSEqC)
If you connect a standard (non-DP) LNB to a DP switch and more than one receiver, you can only get 1 polarity at a time from that LNB. If you only have 1 receiver connected, it has been reported to work fine. I have not tried this.
Multiple receiver switches
If you are using standard LNB (not DP), you need 1 LNB port per receiver, it’s that simple, if you have dual LNB, you have 2 ports so you can connect 2 receivers, if you want a third receiver connected you need a third LNB port.
Single output (not DP) LNBs can only be used with 1 receiver.
But if you have a dual LNB you can expand it to 4 or 8 or even 16 outputs.
This is done with a Multi-switch, they come in 3×4, 3×8 and 2×16.
You run 2 wires from the dual LNB to the multiswitch and then you have 4 LNB outputs (or 8 or 16), if you have 2 LNBs you want then you need 2 multiple switches, one for each LNB.
The 4×4 22khz switch is 2 multi-switches in one case, and you can use them together with DiSEq 4×1 to set up a multi-satellite multi-receiver system.
The C / Ku or 0 / 12v switch is a voltage controlled switch, most FTAs don’t have this option but some do, these don’t work with a coaxial cable signal like 22khz and DiSEqC do, they require 2 wires to The switch, the switch has 2 inputs and one output, at 0 volts one port is connected to 12V the other port is connected.
On the back of the receiver there will be a GND (ground) and 12v (12 volts) this is where the 2 wires are connected to the switch, and there will be a menu option for 0 / 12v ON or OFF.