These Line Cards can be mixed, except that the Loop Current Booster Plus Line Cards are populated in increments of five lines.
Order a modular version of the Line Card you think you need to make sure it fixes your problem before you order a 25 Line Telephony Chassis and the Cards! We'll take an individual unit back if it doesn't help.
The 25 Line Telephony Chassis is a 19" rack mount chassis with 25 pair AMP connectors for input and output. The electronics are exactly the same as the Modular Versions of the Line Cards.
The 25 Line Telephony Chassis is placed in-series with up to 25 analog station ports or phone lines and the phone equipment.
One of the Line Card types is needed in a particular line position for the line to go in and out of the chassis. Without a Line Card, there is no connection between the in and out AMP connectors.
All of the Versions of the Line Cards work with CPC (Calling Party Control, or Open Loop Disconnect), Caller ID, Message Waiting, Distinctive Ringing, Call Waiting, Call Transfer and 3-Way Calling.
The 25 Line Telephony Chassis and Line Cards work on:
There are no switches on the 25 Line Telephony Chassis. There are LEDs to indicate power if you are using Loop Current Booster modules, which are the only type of Line Card that requires power.