DTMF-4HC is an inexpensive, self contained, DTMF decoder or touch
tone decoder board which permits users to control remotely, via
radio or other audio producing source, the on or off state of four
high current devices. For larger applications several DTMF-4HC DTMF
decoder boards can be attached to the same control audio source to
control dozens of devices. DTMF-4HC supports four modes of
operation. These mode settings control how the DTMF-4HC behaves.
Password support is also available for increased protection from
unauthorized entry. All information is stored in non-volatile eeprom
Dimensions: 4 3/4" x 2 5/8" x 9/16"
Weight: 2.2 oz.
Input voltage: 12.0 to 14.0 volts DC (15ma idle, +25ma per
Operating temperature: -10 C to +70 C
Microprocessor: Microchip PIC16F627-20/P (4 MHz)
DTMF / Touch Tone receiver: Motorola MC145436AP
Audio input impedance: 100K Ohms
Audio input level: .1v to 5.0v peak to peak
Relay driver: ULN2803 (open collector outputs 500ma max. each)
Relays: Omron G6C-2114P (sealed)
Relay contact rating: 8 amps @ 12 volts DC / 250 volts AC
Relay contact life: 5,000,000 operations
Factory default mode: Mode 1, no password
Password length: 0 to 9 digits
Valid password digits: 0123456789ABC*#
DTMF-4HC modes of operation:
||All four relays are latched.
Program mode: Press 1.Relays are turned on (*) or off (#) and
remain in that state.e.g. 4* turns on relay 4, 4# turns
the relay 4 off.
||All four relays are momentary.
Program mode: Press 2.The relay is in the on state while the
corresponding DTMF tone is being received and in the off state
when the DTMF tone is absent. This is useful for controlling
devices like pan and tilt cameras.e.g. While 3 is being
pressed relay 3 is on.
||Mix of mode 1 and mode 2.
Program mode: Press 3 followed by the number of relays to be
latched (1-3). The remaining relays are momentary.e.g.
After the user programs 3 for this mode and enters 2 then
relays 1 and 2 are latched (like in mode 1), and relays 3-4
are momentary (like in mode 2).
||All four relays are latched and mutually
Program mode: Press 4 followed by the relay number
that will turn on by default whenever the DTMF-4HC DTMF
decoder is powered up (1-4). This mode is for simplified
control of latched relays (no need for * or #). The relays are
mutually exclusive which means only one of the four relays
will be on. An example application for this is video camera
switching where only one source can be selected at a time.e.g.
Pressing 4 turns on relay 4. Then pressing 1 turns off relay 4
and turns on relay 1.
The DTMF-4HC DTMF decoder is designed to control four devices
(via relays) but it is possible to control more devices by attaching
multiple boards to the same incoming audio source and setting a
password (more of a board ID in this case) for each board.
Warranty & Service:
If the product fails to perform as described in our product
description or specification, within 90 days from the date of
shipment to the buyer, we will repair or replace the product and/or
accessories originally supplied. Failure due to improper
installation, misuse, abuse or accident is not covered by this
warranty. Incidental and consequential damages are not covered by
this warranty. The buyer must obtain a Return Material Authorization
by calling (248) 588-4400, and shipping the defective product to
Intuitive Circuits, 3928 Wardlow Ct., Troy, MI 48083, freight
prepaid. After the warranty expires, we will promptly supply an
estimate for the repair cost.