Alerting the public of an emergency situation is now easier and more reliable than ever with Federal Signal’s Informer I-HIO and I-UIO radio receivers.  Informer units are designed for one-way radio alerting applications.

Informer Radio receivers come in either VHF or UHF-band models. Standard units decode DTMF, single-tone, and two-tone sequential signals (optionally available are units for decoding EAS/SAME or Federal Signal digital protocols). The Informer is capable of generating four separate alarm sounds that can be accompanied by a live voice message.

Informer units include a LED panel that flashes to immediately indicate transmission of an emergency alert. Other features include a 600-Ohm audio output, dual (N.C./N.O.) relay for external control, built-in diagnostics, and an LED test indicator.  The receiver can be programmed to disable the"monitor" button in order to prevent end-users or unauthorized persons from listening to local-channel activity.

The Informer I-HIO and I-UIO desktop versions feature an external AC transformer for power, as well as built-in battery backup.  All wiring is routed to connectors located on the back of the unit for convenient access.

Informer I-HIOW and I-UIOW receivers are designed to be wall mounted or recessed into the wall. All wiring is contained within the aluminum case, and five pre-punched, easy-to-remove conduit holes are available to facilitate wiring connections into and out of the unit.  Informer I-HIOW and I-UIOW receivers include a 115/230VAC power supply pre-wired to internal terminal blocks and a built-in battery backup. These models feature mounting holes for easy top mounting of an optional Federal Signal LP1 Strobe light. Units are pre-wired to accommodate the LP1 Strobe which operates off the Informer’s internal power supply.

Informer units are factory programmed for narrow-band operation and come with a one-year warranty (see owner’s manual).

Note: The I-HIO and I-UIO have mounted two holes on the underside so that it can be mounted on a wall LP1-012* can be installed on I-HIOW/I-UIOW (wall mount units) only.



Frequency Range (MHz) 150-170
Narrowband 405-420*
Intermodulation Rejection per EIA-603, part 4.1.9 >-75 >-70
Adjacent Channel Selectivity per EIA-603, part 4.1.6 >-70 >-65
Spurious Response & Image Rejection (dBm) per EIA-603, part 4.1.8 >-75 >-70
Reference Sensitivity1: (12dB SINAD) < 0.35 microvolts
Hum and Noise1
Squelched >-57 dB(C)
unsquelched >-37 dB(C)
AC Transformer (UL Listed)
Input I-HIOW/UIOW 115 to 230VAC, 50/60 Hz
General Text I-HIO/UIO 108 to 128VAC, 60Hz
Operating Environment -22º F to 140º F -30 to +60°C
Operating Current I-HIOW/UIOW 350mA Maximum
I-HIO/UIO <400mA Max
Standard Signaling Formats Number of codes
Up to 6 activation codes, programmable
Two-Tone Sequential or Single Tone 300 Hz-3000 Hz, tolerance +/- 1.5%
DTMF 1-12 digits
Two-Tone and DTMF Decode Sensitivity <20 dB(C) SINAD
Decode with two-tone codes >400 Hz only.
Tone frequency range 36.6 to 254.1 Hz, Tone accuracy >.05Hz
Tone decode bandwidth +/- 1.1%
Digital, golay (23,12) 23 bit digital word
Digital data rate 134.4 Hz nominal
Decode Turn on time <250ms., Turn off Time <1.2s.
Acoustic Output:2 I-HIOW/UIOW 80 dB(C)
I-HIO/UIO 85 dB(C)
External Control/Audio/Antenna
Dual (N.O./N.C.) relay 5a @ 30VDC
600 Ohm output 50mv - 2.5vpp into 600 Ohms
Antenna Removable rubber duck
External Antenna Connector 50 Ohm, BNC female
I-HIOW/UIOW 8.3" x 7" x 3.3"
210.8 mm x 177.8 mm x 83.82 mm
I-HIOW/UIOW 3.2 lbs (1.45 kg)
I-HIO/UIO 4 lbs (1.81 kg)

Ordering Information

Model Types
Model Description UPC
I-HIOW Wall mount, VHF high band, 150-172 MHz 782979701057
I-UIOW Wall mount, UHF band, 450-470 MHz 782979701149
I-HIO Desk mount, VHF high band, 150-172 MHz 782979701040
I-UIO Desk mount, UHF band, 450-470 MHz 782979701132
Product # Description UPC
I-EAS Factory installed EAS 782979701002
I-EAS-KIT Field installable EAS kit 782979701019
I-FSK Factory installed AFSK
I-FSK-KIT Field installable AFSK kit
I-SW Programming software 782979701125
USB USB Programmer
Replacement Parts
Description Part Number
Radio Informer replacement battery 155191A