3
power source. The black wire must be connected to
the negative terminal of the power source.
Alternatively, the LPM-33 can be powered by a
nominal 12 Vac source. A Stancor STA-4112A wall
mount transformer can be used for this purpose. It
connects directly to any 120 Vac outlet. The
transformer has a rated output of 12 Vac at 500 mA.
Its output cable is terminated with a 3.5 mm plug.
Note - Contact MICRO-AIDE if the Stancor wall
mount transformer is required.
Setup and Operation
Except as noted below, after power is applied to the
LPM-33 the green “STBY” LED should start to flash
immediately. This indicates the modem is in low
power standby mode. The LED should turn off when
the modem receives DTE data or auto-answers an
incoming call.
The standby mode of the LPM-33 can be disabled.
This option may be of benefit in applications where
the modem is not being powered by a solar panel.
Disabling the standby mode of the LPM-33 forces
the modem into continuous active mode.
To disable standby mode remove the cover of the
LPM-33. Four screws located along the sides of the
modem secure the cover in place. Locate the jumper
labeled “JP1” on the printed circuit board. Install the
shorting jumper so that it bridges both pins of JP1.
Reattach the cover. The standby LED will remain
off with power applied to the modem.
Reminder - For low power standby operation
remove the JP1 jumper. To disable standby
operation install the JP1 jumper.
The user may be required to install an operational
profile into the LPM-33. Modem profiles are
determined by the operating aspects of the DTE
attached to the LPM-33 and the required application.
The LPM-33 conforms to the industry standard set of
AT commands. However, several modem
characteristics (e.g., error correction control) are not
uniformly coded by modem chip manufacturers. A
complete list of AT commands used by the LPM-33
is available.
Note - Contact MICRO-AIDE if a complete
description of the AT command set used by the
LPM-33 is needed.
Install and save the required profile by connecting
the communications port of a PC directly to the
RS-232 connector of the LPM-33. A
communications program (e.g., HyperTerminal®)
can be used to communicate with the LPM-33.
Note - Unless otherwise requested by the user, both
profiles used by the LPM-33 are set to the default
values established by the modem chip manufacturer.
After the correct profile is programmed into the
LPM-33 the modem is ready for use in the intended
application.
Maintenance and
Trouble-shooting
The LPM-33 is designed to be completely
maintenance free. It contains no consumable
materials or serviceable components. If the unit fails
to power-up (as indicated by the green standby LED
not flashing) the unit should be returned to
MICRO-AIDE for repair.
The operation of the LPM-33 can be easily tested.
Any PC equipped with a modem and a
communications program (e.g., HyperTerminal®)
can be used to access the LPM-33. A check of the
modem’s ability to answer, connect and communicate
can be performed very effectively. Remote tests of
the LPM-33 can be made by MICRO-AIDE
technicians at the request of the user.
MICRO-AIDE provides a limited three-year
warranty of the LPM-33. Telephone numbers and a
shipping address are listed below.
MICRO-AIDE CORPORATION
685 Arrow Grand Circle
Covina, CA 91722
Tel: 626-915-5502
Fax: 626-331-9484
