1989 Norstar Meridian Field Trial NT8B50 (M7900)
This field trial development set, initially designated as a “NT8B50,”
evolved into the Norstar Meridian M7900 Touchphone.
Meridian M7900 Northern Telecom’s first prototype Touchphone.
A telephone with all indicators and functions managed by a Touchscreen.

A quote from former BNR empolyee who donated this Touchphone.
I worked at Nortel in the 80s – in the Design Interpretive group under John Tyson.
“My contribution was on the product definition and user interface design side. As far as I know, when we were working on it, it was the first phone to use a touch-sensitive screen.”

As received January 18th 2024.

Added a KSU Norstar 616 non DS and running DR5 software, plus a ATA NT8B90CA.

The screen saver automatically powers down after a period of inactivity.

Another Meridian M7900 has surfaced, Tim Griffin,
a fellow collector, recently contacted me to share that he owns one.
He provided images of his Black M7900 Touchphone.

The Norstar Meridian SL-100 M3000 Touchphone is the successor to the Meridian M7900.

https://www.oldtelephoneroom.ca/norstar-meridian-sl-100-m3000-touchphone/