The Engineering team found issues with adding telephones into PLs – they would cause dialing problems.
Using EHX v12.2 is it currently not possible to add a telephone (TEL-14 or LQ-SIP) as a member of a PL. The ability to add telephone members to partylines has been removed.
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Drag on a Latch, and a Control Output (O/P). Connect to the /Q (q-bar, normally closed) to the Control O/P and then add the new control into the O/P control area.
Assign the TEL-14 key per normal to your panel for dialling out