See similar Motorola terminal: http://www.mobilecollectors.net/phone/3223
According to nokiamuseum.com:
The Nokia 11 Wireless Local Loop terminal is a faster and easier way to
gain traditional telephone subscriptions. Take the terminal wherever
you want within the NMT 450 network coverage area and connect it to the
mains and to a traditional telephone. You're now ready to make a phone
call.
Dimensions
200 x 114 x 32 mm
Weight
740g
Cover material
Cast aluminum
Power supply
13.3 V / 3.0 A
Output power levels
0.15 / 1.5 / 7W
Temperature range
-25...+55 centigrade
Nominal battery voltage (BBW-3)
12 V
Nominal current consumption
Standby mode 150 mA
Call mode 3.0 A
Telephone interface
RJ-11 connector
Possibility to connect 3 parallel phones
Telefax interface
RJ-11 connector
Line impedance
600 ohm
Line voltage
-52 V +- 2.5 V
Ringing voltage
-68 Vrms +- 2.5 V
Charging pulse frequency
12/16 kHz
Mounting base
Dimensions 15 x 122 x 197 mm
Weight 100 g
Backup battery
Optional. Talk time:
3 h 20 min (0.15 W),
1 h 40 min (1.5 W),
40 min (7W)
Standby time: 15 h
Antenna
TNC connector in transceiver.
Standard 1/4 dipole antenna.
Optional high-gain directional and window antenna.
Security
Based on NMT 450 standard
Subscriber Identity Security (SIS)
Speech scrambling
Other supported features
Calling Line Identification (CLI)
Charge Advice Information (CAI)
Automatic Area Code (AAC)