Back in the 1980’s AT&T was the biggest manufacturer of business telephone equipment. Their number one seller was the AT&T Merlin phone system. It was a huge improvement over the much larger business phones of the time. The Merlin phones were extremely well made, so well so they are still on the market today. The Merlin system allowed for users to place multiple calls on hold, had music on hold, and was flexible with the number of lines and phone extensions.
Today there are still many companies that have the Merlin phone system from the 1980’s. While over time these users may have replaced phones or handsets, no one can argue about how overall reliable this system was. Unfortunately, we are coming to a time so distant from when this system was manufactured that the phones greatly outnumber the available systems on the market. While Merlin BIS-10 phones are still plentiful and working, the older Merlin Classic 206, 410, and 820 systems are much harder to come by. These systems, even if found, are not as reliable as they were when originally created having problems such as bad power supplies, warning lights, and calls bleeding over.
AKA Known As 206, 410, or 820
AKA Known As 820D or 820D2
There is a solution for the time being, the Merlin Plus system. The AT&T Merlin Plus phone systems are compatible with the Merlin phones that are used on the Merlin Classic systems. The Merlin Plus system is different than the Classic in some ways. The Plus has music on hold built and does not require a Feature Package. The Merlin Plus system uses 4x0 line cards and 0x10 stations cards. Each 4x0 line card will provide you with four incoming lines. You can use up to 2 4x0 line cards per Merlin Plus system to allow for up to eight incoming lines. Then you can have up to 2 0x10 station cards, each card allowing for up to 10 phones for a maximum of 20 phones per system.
The Merlin Plus system is a great alternative to keeping your Merlin phones going versus having to upgrade your whole system. You will be able to keep your existing phones and wiring in your building and swap the Merlin Classic system for the Merlin Plus system. Manuals for these systems are available online for free as PDF files and you can always hire a professional to make the change for you.