What are you trying to page? A pre-recorded / canned message or something on-the-fly? Also, what are you paging to (analog station ports hooked up to an amp, SIP paging interfaces, digital/IP sets)?
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For canned messages our typical use-case is an evacuation alert. We build a module that plays a greeting of "You are about to set off the big noisy siren. If this is a mistake hang up now. 3. 2. 1" then post-dial a .WAV of an air raid siren to PAGE:ext#. When the call hits the post-dial block you get a "Delivered" prompt played back to you. No reason you can't have multiple post-dials chained together. The person setting it off would just listen for 3 or 4 or 5 or whatever "Delivered" messages before disconnecting.
Or make one big group and page them all at once with a single post-dial.
This works for the Algo SIP Alerter if programmed for Device auto answers, the analog station port connected to an amp, and/or digtial/IP stations.
If your device requires ring voltage to trip (like a TAM-B) then you don't want to PAGE the post-dial, just put in the ext number, and you'll have to do the chain of them (I think).
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For a one-off page, I'd think you would need to record a .wav then hit the post-dial block(s) pointing at that .wav.
- Qz