
KEYSTONE HEDDOLF T-931-MH
TYPE: FIR311DEK31K • FCC ID: SU7311DEK31K
This device complies with Part 15 of the FCC Rules.
Operation is subject to the following two conditions:
(1) This device may not cause harmful interference, and
(2) this device must accept interference received, including
interference that may cause undesired operation.
Manual - 311 1 Button
KEYSTONE HEDDOLF
DEK CANADA INC.
T-931-MH
NOTICE
Any changes or modifications to this equipment not expressly approved
by KEYSTONE HEDDOLF could void the manufacturer’s warranty and could
void the user’s authority to operate the equipment.
WARRANTY
The warranty period of the Firefly3™ transmitters is twenty-four
(24) months. This warranty shall begin on the date the transmitter is
manufactured. During the warranty period, the product will be repaired
or replaced if the product does not operate correctly due to a defective
component. This warranty does not extend to (a) the transmitter case, which
can be damaged by conditions outside the control of KEYSTONE HEDDOLF,
or (b) battery life of the transmitter. This warranty is further limited by the
following disclaimer of warranty and liability:
EXCEPT AS SET FORTH ABOVE, KEYSTONE HEDDOLF MAKES NO WARRANTIES REGARDING THE GOODS,
EXPRESS OR IMPLIED, INCLUDING WARRANTY OF MERCHANTABILITY OR WARRANTY OF FITNESS
FOR A PARTICULAR PURPOSE. BUYER MAKES NO RELIANCE ON ANY REPRESENTATION OF KEYSTONE
HEDDOLF EXPRESS OR IMPLIED, WITH REGARD TO THE GOODS AND ACCEPTS THEM “AS-IS/WHEREIS”. KEYSTONE HEDDOLF SELLS THE GOODS TO BUYER ON CONDITION THAT KEYSTONE HEDDOLF
WILL HAVE NO LIABILITY OF ANY KIND AS A RESULT OF THE SALE. BUYER AGREES THAT KEYSTONE
HEDDOLF SHALL HAVE NO LIABILITY FOR DAMAGES OF ANY KIND, WHETHER DIRECT, INCIDENTAL
OR CONSEQUENTIAL DAMAGES, INCLUDING INJURIES TO PERSONS OR PROPERTY, TO BUYER, ITS
EMPLOYEES OR AGENTS, AS A RESULT OF THE SALE. BUYER ALSO AGREES TO HOLD KEYSTONE HEDDOLF
HARMLESS FROM ANY CLAIMS BUYER, OR ANY THIRD PARTY, MAY HAVE AS A RESULT OF BUYER’S USE
OR DISPOSAL OF THE GOODS. BUYER HAS READ THIS DISCLAIMER AND AGREES WITH ITS TERMS IN
CONSIDERATION OF RECEIVING THE GOODS.
For more information,
please visit www.devancocanada.com
TRANSMITTER
Please read these programming instructions carefully
before using the product.
Made in Taiwan.
CONTENTS
1 - TRANSMITTER OVERVIEW
1A - General information
2A - Technical specifications
1C - Main components
3 - PROGRAMMING
4 - OPERATION
5 - BATTERY ACCESS
6 - TROUBLESHOOTING
1A - General information
The KEYSTONE HEDDOLF - Firefly™ Transmitter is a very small
(1-1/2” x 2-1/8” x 3/8”) key chain style wireless transmitter
operating at 311 MHz.The Firefly™ achieves its small size by using
state-of-the-art, surface mount components. It has been designed
for use with dip switch receivers operating at 311 frequency.

Black Case with Black Button
Operating frequency : 311 MHz
Number of buttons : 1
Battery : 1 ea. 12V A23
Operating temperature : -20°F - 85°F
Overall dimensions : 1-1/2 x 2-1/8 x 3/8 inch
Weight: 1 oz.
2 - NUMBERING
3 - PROGRAMMING
4 - OPERATION
5 - BATTERY ACCESS
6 - TROUBLESHOOTING
by conditions outside the control of DEK Canada Inc., or (b) battery life of
the transmitter. This warranty is further limited by the following disclaimer of
warranty and liability:
EXCEPT AS SET FORTH ABOVE, DEK CANADA INC. MAKES NO WARRANIES REGARDING THE GOODS,
EXPRESS OR IMPLIED, INCLUDING WARRANTY OF MERCHANTABILITY OR WARRANTY OF FITNESS FOR A
PARTICULAR PURPOSE. BUYER MAKES NO RELIANCE ON ANY REPRESENTATION OF DEK CANADA INC
EXPRESS OR IMPLIED, WITH REGARD TO THE GOODS AND ACCEPTS THEM “AS-IS/WHERE-IS”. DEK
CANADA INC SELLS THE GOODS TO BUYER ON CONDITION THAT DEK CANADA INC WILL HAVE NO
LIABILITY OF ANY KIND AS A RESULT OF THE SALE. BUYER AGREES THAT DEK CANADA INC SHALL HAVE
NO LIABILITY FOR DAMAGES OF ANY KIND, WHETHER DIRECT, INCIDENTAL OR CONSEQUENTIAL
DAMAGES, INCLUDING INJURIES TO PERSONS OR PROPERTY, TO BUYER, ITS EMPLOYEES OR AGENTS, AS
A RESULT OF THE SALE. BUYER ALSO AGREES TO HOLD DEK CANADA INC HARMLESS FROM ANY CLAIMS
BUYER, OR ANY THIRD PARTY, MAY HAVE AS A RESULT OF BUYER’S USE OR DISPOSAL OF THE GOODS.
BUYER HAS READ THIS DISCLAIMER AND AGREES WITH ITS TERMS IN CONSIDERATION OF RECEIVING THE
GOODS.
1908 St-Regis Blvd.
Dorval, Quebec, Canada
H9P 1 H6
www.dekcanada.com
The DEK Canada Inc. - Firefly™ Transmitter is a very small (1-1/2” x
2-1/8” x 3/8”) key chain style wireless transmitter operating at 311 MHz.
The Firefly™ achieves its small size by using state-of-the-art, surface mount
components. It has been designed for use with dip switch receivers
operating at 311 frequency.
2 - NUMBERING
3 - PROGRAMMING
4 - OPERATION
5 - BATTERY ACCESS
6 - TROUBLESHOOTING
The DEK Canada Inc. - Firefly™ Transmitter is a very small (1-1/2” x
2-1/8” x 3/8”) key chain style wireless transmitter operating at 311 MHz.
The Firefly™ achieves its small size by using state-of-the-art, surface mount
components. It has been designed for use with dip switch receivers
operating at 311 frequency.
Operating frequency : 311 MHz
Number of buttons : 1
Battery : 1 ea. 12V A23
Operating temperature : -20°F - 85°F
Overall dimensions : 1-1/2 x 2-1/8 x 3/8 inch
Weight: 1 oz.
Black Case with Black Button