Midian Electronics TTD-5 User manual

TTD-5
Single Digit DTMF Decoder
Manual Revision: 2007-01-23
Covers Hardware Revision:
TTD-5: C & Higher
SPECIFICATIONS
Operating Voltage 5.5-18 VDC
Operating Current 7 mA
Operating Temperature -30 - +60 C
Input Level 25-500 mV RMS
Outputs 200 mA
Dimensions 1.35” L x 0.85” W x 0.3” H
GENERAL INFORMATION
The TTD-5 is a single digit DTMF decoder with 16
outputs. Each output corresponds to each of the 16
DTMF digits (0-9,*, #, A-D). The outputs can be
either momentary or latched and only one output
can be active at any given time.
HARDWARE INSTALLATION
Be certain to follow standard anti-static procedures
when handling any of Midian’s products.
Connector P1
P1-2 – Red – VIN +5.5-18 VDC – Connect to
switched battery point in the radio. Connect to a
regulated voltage point in a vehicular radio if engine
noise is present on the battery line. Keep this lead
as short as possible.
P1-4 – Black – Ground – Connect to the nearest
ground plane in the radio.
P1-6 – Orange – Tone Input – Connect to an audio
point in the receiver, usually the high side of the
volume control or discriminator output. When using
CTCSS, pick up the audio after the high pass filter.
P1-7 – Yellow – Output Tone #
P1-8 – Green/White – Output Tone *
P1-9 – White – Output Tone A
P1-10 – Gray/White – Output Tone B
P1-11 – Gray – Output Tone C
P1-12 – Orange/White – Output Tone D
Connector P2
P2-4 – Black – Output Tone 0
P2-5 – Blue – Output Tone 9
P2-6 – Orange – Output Tone 8
P2-7 – Yellow – Output Tone 7
P2-8 – Green/White – Output Tone 6
P2-9 – White – Output Tone 5
P2-10 – Gray/White – Output Tone 4
P2-11 – Gray – Output Tone 3
P2-12 – Orange/White – Output Tone 2
P2-13 – Violet – Output Tone 1
HARDWARE ALIGNMENT
Note: The TTD-5 has a time constant of 300 msec
to prevent falsing on voice talkoff. It is possible to
shorten this time constant by replacing C2 with a
smaller value capacitor or increase the time constant
by replacing C2 with a larger value capacitor.
PRODUCT PROGRAMMING
The TTD-5 is a hardware based product and no
programming is required.
OPERATION
Momentary Output: With JU1 installed the outputs
give a momentary output. The voltage on IC1 Pin 15
(present only with a DTMF input) is passed through
JU1 to the common, pin 3 of IC-2 and IC-3. Because
voltage is only present when receiving DTMF the
selected output will be low only as long as DTMF is
1

present. All outputs will float with JU1 installed,
unless DTMF is present at the input.
Latched Output: With JU2 installed the outputs give
a latched output. When JU2 is installed, one of the
16 output pins will randomly latch on power up.
When DTMF is decoded the corresponding output
will go low and latch until another valid DTMF digit is
decoded, at which time the latched output will
unlatch and the corresponding output of the new
DTMF digit will latch. The voltage coupled through
JU2 is passed through the common, pin 3 of IC-2
and IC-3, to the output selected via the binary input
on pins 9, 10 and 11. When DTMF is not present the
binary number on these pins of IC-2 and IC-3 is not
removed until another binary number replaces it.
TECHNICAL NOTES
Radio Compatibility: Midian has taken the utmost
care to ensure the option board integrates into the
radio with minimal impact to the features of the
radio. However, some features may not be available
in the radio when an option board is used. If a
feature is not available, please contact Midian to see
if the feature can be added.
MIDIAN CONTACT INFORMATION
Midian Electronics Inc.
2302 East 22nd Street
Tucson, Arizona 85713 USA
Orders: 1-800-MIDIANS
Phone: [phone]
Fax: [phone]
E-mail: [e-mail]
Web: http://www.midians.com/
2