Compaq 1610 Reference Manual page 127

This equipment shall not be used in any manner which could
constitute a nuisance to other New Zealand Telecom customers.
1. The modem is suitable for connection to the Public Switched
Telephone Network (PSTN) direct exchange lines and
relevant branch systems (PBXs).
2. A ringer approximate loading (RAL) is a value given to all
apparatus to be connected to the PSTN. Its value can be taken
and used to calculate the maximum number of equipment
items that can be connected in parallel without impairing the
performance of the standard bell circuit.
The maximum RAL value for telephone equipment is 5.
Exceeding the RAL value of 5 may cause your telephone(s)
to ring weakly or not ring at all.
Only one modem should be connected to a telephone line.
Connecting a modem in parallel with one or more
telephone instruments is not allowed.
3. The RAL for this piece of equipment is 1.0.
4. The exchange should provide facilities for either loop
disconnect (pulse) dialing or multifrequency (tone) dialing.
The modem can be configured to operate with either system.
5. The operation of this equipment on the same line as
telephones or other equipment with audible warning devices
or automatic ring detectors will give rise to bell tinkle or noise
and may cause false tripping of the ring detector. Should such
problems occur, the user is not to contact Telecom Faults
Service.