Trigger 2 Relays At Once

I know this may seem like a silly question but I just more want to be sure I can do it without overloading the output.

Lets say I have this little Audio switcher PCB, it’s about as simplistic as you can get which is just what I want.
My multimeter reveals that the onboard switch changes the 6 connections on the PCB like this:

The top 2 points are connected to the middle 2 point although separately down each side… you could join them if you just wanted a mono Audio signal.

And the bottom 2 point connect to the middle 2 point again separately down each side.

Now what I need to do is remove the on board PCB switch and have a couple of relays do the job of the switch.

The Normally closed positions on both relays would naturally be the default state of the switch and then when both relays are triggered they would connect the top connections of the PCB points to the Middle two points… Hopefully that made sense as far as the basic workings of this little PCB goes??

Now what I’m just wanting to make sure about is can I safely have the one of the Arduino pins trigger 2 relays to do this job??

NOTE: See attachment for an image of he switch connection on the little PCB Audio switcher board.

An Arduino cannot trigger even one relay savely, this should be done via an external circuit like a transistor or a MOSFET. And don't forget the fly-back diode!

pylon:
An Arduino cannot trigger even one relay savely, this should be done via an external circuit like a transistor or a MOSFET. And don't forget the fly-back diode!

Thanks, Yes I did know that I forgot to mention that I was referring to a Relay module that already has optocouplers for circuit isolation.
In such case can I use one Arduino pin to trigger 2 relays at the same time in that case?

It should be OK but if you're paranoid you can use two Arduino outputs...

Do you have the (detailed) specs for the relay module? Or a schematic? Or can you read the value on the current-limiting resistor going to the opto-isolator?

DVDdoug:
It should be OK but if you're paranoid you can use two Arduino outputs...

Do you have the (detailed) specs for the relay module? Or a schematic? Or can you read the value on the current-limiting resistor going to the opto-isolator?

Thanks @DVDdoug,

I'm always a little perhaps over paranoid with this suff :wink:
But eventually it's this type of relay module :slight_smile:

https://www.ebay.com/itm/5V-8-channel-Relay-module-isolation-High-low-level-trigger-FOR-Arduino-uno-R3/181870113008?epid=885265583&hash=item2a584db0f0:g:GcYAAOSwEetV9wwR

Trigger current is 5mA (if the vendor provides correct information) so triggering two of these inputs with one Arduino pin shouldn't be a problem.

pylon:
Trigger current is 5mA (if the vendor provides correct information) so triggering two of these inputs with one Arduino pin shouldn't be a problem.

OK thanks @pylon
So I should not need to add any resistors or anything like that?

So I should not need to add any resistors or anything like that?

If the information is correct: no.