Setting up virtual relay for AlarmDecoder with Vista 20p with built-in zones

I have a Honeywell/Ademco Vista 20p. My system is set up making use of the 8 built-in zones, but also using the “zone doubling” mentioned in the installer’s manual where you can wire up some extra resistors and wire two different zones to (most of) the same built-in terminals on the board, yielding a max of (I think) 14 or 15 built-in zones.

My understanding from reading the wiki for the old OH1 AlarmDecoder binding (I’m using the OH2 binding, but the OH1 binding has some interesting info in its docs) is that I must set up a virtual relay or I won’t get any events for the built-in zones (which for me, is all of them). There is a link in the wiki that points to a detailed guide on how to set up the relay at the alarm panel ( but it unfortunately appears that site is down, possibly permanently.

I’ve read through the alarm’s programming manual, and attempted to set up a relay, setting it up to send events for one of my zones. However, when I then fault that zone, nothing happens. So clearly I’m misunderstanding how to set this up. Does anyone have a link to an alternative guide, or perhaps personal experience they can detail here?

And literally two minutes after posting this, I thought to check the Wayback Machine, which does appear to have a snapshot of this page!

I’m going to try all that and then perhaps transcribe it to post back here for posterity.

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