This switch allows you to switch 2 RF signals to one common port. In addition, you can switch two other signals, for example PTT and ALC. For this purpose there is a double switch with RCA connectors. The switch comes in two varieties - in the first the unused ports are grounded, in the second they are connected to 50 Ohm resistors.

The switch can transmit RF power up to 4kW. It also features very high isolation, over 100dB at frequencies below 30MHz.

The switch can be used to switch one TRX to two PAs (e.g. HF and 6m or another HF monobander and multiband PA), also to switch two TRXs to one PA etc.

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Applications
Parameters
Versions
Control
Measurements
Product details

Applications

- Two TRX to one PA
- Two PA to one TRX
- Middle switch between another switches (6-to-2)
- Switch for triplexes (version with dummy loads)

Two TRX to one PA (antenna)

Two PA to one TRX

For example, if you have two PAs where one is monoband and the other is multiband. Alternatively, two monobanda PAs etc.

Switching between triplexers outputs

Example where you need to switch filters or triplexers, where the disconnected port needs a 50 Ohm dummy load for better parameters. Don't forget to properly calculate the power and isolations (filter and antennas) to avoid overloading the internal resistance in the switch. More here on the page.

Parametrs

- Frequency range DC-50 MHz
- Characteristic impedance 50 Ohm
- Low insertion loss
- Very high isolation > 100 dB to 30 MHz
- Control voltage DC 12.5 to 14V
- Control current up to 0.3A
- Two RCA switches 1A 30V DC
- Unused port grounded or 50 Ohm
- Power rating DC to 30 MHz

Versions

SHORT

In this version, unused ports are connected to ground - shorted. Without control voltage, both ports are grounded.

DUMMY LOAD

In this version, the unused ports are connected to an internal 50 Ohm resistor. Without control voltage, both ports 1 and 2 are connected to this resistor.

The internal 50 Ohm resistor is a 100W chip. However, it does not include cooling. The possible load is 100W peak for 2 seconds. In a 50:50 ratio, the resistor can be loaded with 5W of RF power.

DUMMY LOAD - power loading

In the version of the switch with internal dummy load (DUMMY LOAD) there are two 50 Ohm resistors with a maximum load of 100W. But the switch does not include cooling. Therefore, it is not possible to supply this power to the resistors for a long time. It would destroy the switch.

The power load is as follows:

- 100W RF power for a maximum of 2 seconds
- With a 50:50 ratio, the resistor can be loaded with 5W of RF power

I recommend a good measurement on your setup. If you have a 2-port VNA, you can measure isolation between antennas, between bands, etc. If using a triplexer and internal dummy load, measure the triplexer isolation between bands. At 1kW of power it should be better than 30dB. The problem can also occur if you have multiple antennas on one band and the transmitted signal is returning from one antenna to another. Isolation should again be better than 25dB.

Control

The switch contains a green connector for connecting control voltages. The common port is GND. You can then choose how to control the switch. Without control voltages connected, no port (1 or 2) is connected to the Common port. Depending on the variant, ports 1 and 2 are connected either to ground or to a 50 Ohm dummy load.

Control is possible in two ways:

1. By applying a voltage to the appropriate port 1 or 2
- TOP part of the connector in the picture
- Apply a voltage of 12.5 to 14V DC to PORT 1 or PORT 2
- Voltage is applied against port GND - the middle pin on the connector
- this is where the First Win function works

2. Switching without the first win function
- BOTTOM of the connector
- by supplying 12.5 to 14V DC to port 13.8V, PORT 1 is activated
- applying 8 to 14V DC to PORT 2 switches to PORT 2

Measurements

Isolation Port 1 to Common

S11 matching Port 1 to common