Two spectras/one siren box

[phillipsc84]

So here's the question. Who can point me in the right direction as to the possibility of having two spectras connected to one siren so that both can have Ext. Radio cpapbilities...? I can imagine it being easier or at least possible with the X9000s since they have the T connectors but how aould it be done with two spectras?

[kc7gr]

I've explored this issue a couple of times. The only way I can see to reasonably do it is to have two siren boxes, one per radio, and to have a relay switch the speaker from one box to the other. I've not figured out a good way to trigger the relay, as I've not found a way to make a VIP output change state when the 'PA' function is invoked.

The problem you're going to run into is that the radio expects to see the siren box on the data bus. If you disconnect and reconnect it, as in switching between two radios (and you'd probably need something like a 20-pole double-throw relay to do so properly in any case), you're going to cause issues with bus corruption. You could end up having to power-cycle the radios every time you switch the siren box back and forth.

If you DO find a decent way to do it, please do tell the rest of us!

Happy tweaking.

[Bruce1807]

are you just trying to make one or the other radio come out the siren speaker.
Just find the audio in on the siren (Its in the mnanual)
and put a change over switch for radio 1 and radio 2.
Radio 1 would still select ext radio but the audio should be from radio 2.
I dont remember any pull ups for cor or anything but will look tomorrow.