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RF Relay/Switch Electromechanically Auto Control - need control method recommendation

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Advanced Member level 4
Jul 24, 2006
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I have a project which is to design a system for RF switching.
The control of the switching should be done automatically using a control interface via a PC program.
The RF switch is a simple SPDT (Single Pole Double Through; known is 1 to 2 relay) which deliver an RF power to the appropriate state (Common port to port 1 or port 2).
When trying to design the system for that I noticed for few types of Relays/Switches one of them and the most wide used is the regular relay which have Power input terminals of 28V – the control is done when closing a 28V voltage between a Common and a chosen terminal (say no. 2) so the actuator will be closed and to pass the RF into path no. 2 – while there are other type which have instead of 28V input a TTL (5V) control inputs which activate the correspondence actuator but using a simple logic driver – the former type of relays are more common in more in-stock the later one.
My question is, even though I prefer using the simple TTL type for the Relays (using a readymade controller board with integrated I/O pins for simple control over software) – what would be a recommended relay + current driver if we will work in the non-TTL type relay and will try to control the 28V from a PC?

As far as i understand, the 28V are used to power the actuator...and you want to control via PC PIN which gives 5V. you can use a simple optocoupler to switch 28V using your computer PIN. If current requirement of the actuator is high you can cascade a darlington to drive it or use single pole double through relay to switch your RF relay (assuming the switching frequency is not high)


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