Contemporary Research 232-MTA User manual

17630 Davenport Road, Suite 113 • Dallas, TX 75252
Phone: [phone] • Toll-Free: 888-972-2728 • Fax: [phone]
E-Mail: [e-mail] • Website: www.crwww.com
Product Manual
232-MTA
Stereo TV Tuner
Ver. 4.4 June 27, 2007

Contemporary Research 2 232-MTA Mono TV Tuner
Table of Contents
Overview.............................................................................................................................................3
New Features (Rev 3.3-4.0) ....................................................................................................................3
Specifications......................................................................................................................................4
Physical.................................................................................................................................................4
Front Panel............................................................................................................................................4
Rear Panel.............................................................................................................................................4
RF Tuner...............................................................................................................................................5
Includes ................................................................................................................................................5
Options .................................................................................................................................................5
Troubleshooting..................................................................................................................................6
Front Panel Programming...................................................................................................................6
Modes 10 and above ..............................................................................................................................6
Front Panel Programming Commands................................................................................................7
RS-232 Control Protocol.....................................................................................................................8
Overview...............................................................................................................................................8
General protocol specifications ................................................................................................................8
Command String Structure......................................................................................................................8
Command and Status Response...............................................................................................................8
General RS-232 Commands.....................................................................................................................9
Character Generator Commands............................................................................................................11
Keypad Channel Command....................................................................................................................12
IC-RC Remote Emulation.......................................................................................................................12
Tune Ring Commands and Replies.........................................................................................................13
Terminal Communication Commands .....................................................................................................13
RS-232 Command Hints and Tips...........................................................................................................13
Response Strings ..............................................................................................................................14
Channel/Source Status Response String (T):...........................................................................................14
Audio Status Response String (V): .........................................................................................................14
Front Panel Mode Status Response String (S):........................................................................................14
RS-232 Cable Connections................................................................................................................15
Single Tuner ........................................................................................................................................15
Multiple Tuners ....................................................................................................................................15
Rack Mounting..................................................................................................................................16
RK1 Single Unit Rack Mount..................................................................................................................16
RK2 Side-by-Side Rack Kit.....................................................................................................................16
Safety Instructions...........................................................................................................................17
Limited Warranty and Disclaimer.....................................................................................................18

Overview
The Contemporary Research 232-MTA is a versatile RS-232 controlled monaural TV tuner featuring high-quality
mono audio, 125-channel access in Off-Air, Cable, HRC, or IRC modes, front-panel operation and feedback, and
intelligent control. Fully programmable, the unit can restore all settings on power-up from non-volatile memory.
A list of accessible channels, called channel rings, can be stored in memory, used for convenient channel
up/down control and to control direct access to unlisted channels.
The front-panel buttons and alphanumeric display can be used for general operation and to program basic
features for tuning, RS-232 baud rate and local control. Full setup, control, and feedback is provided by RS-232.
Up to nine 232-series tuners can be controlled from a single RS-232 port. In addition, remote tuning ring channel
up and down operation can be accessed through contact closure inputs.
•Interacts with PCs and control systems via RS-232, using simple ASCII-format commands and feedback,
up to nine tuners can be linked to a single RS-232 control port
•Tunes 125 channels in off-air, CATV, HRC, or IRC modes, using true synchronous video detection and
intercarrier SAW filter
•Stores programmable tuning ring in memory to control channel access
•Provides front-panel control for A/V Mute, mode select, and channel up/down, with LED feedback
for Mute, current channel and programming mode
•Accesses tuning ring channel up/down from contact closure inputs
•Restores all operation status after loss of power from data stored in non-volatile memory
•Mutes both audio and video with front-panel LED indicator
•Delivers mono unbalanced audio at fixed volume and mute levels
•Enables and disables front-panel control via RS-232
•Mounts in 19" rack with optional RK1 or RK2 kit for dual side-by-side installation
•Firmware updateable via modem or PC software (available soon)
New Features (Rev 3.3-4.0)
•Shares new processor from 232-STS S-Video Stereo Tuner
•Adds new front-panel (12-14) and RS-232 programming modes (Q2-Q4) to match 232-STS
•Upgradeable firmware, presently updated via modem from factory, software tools available soon for
local update
•Units shipped with new processor start with serial number 229-5017-001, Rev 3.4 or higher
Serial number can be read as follows—xxx (production run) - 5017 (232-MTA) – xxx (unit number)
•Request Tune Ring and Channel Label (V3.4)
•IC-RC Remote emulation (V3.4)
•Up to nine units can be controlled from a single RS-232 control port, up to 19.2 Kb (V 3.5)
•Sending a command to Unit#0 (Zero) acts as a global command to all tuners (V4.0)
Contemporary Research 3 232-MTA Mono TV Tuner

Specifications
Physical
Size: 8.5" [216mm] wide x 1.75" [38mm] height (1RU) x 6.0" [153mm] deep
Weight: 1.5 lbs [0.68kg]
Enclosure: All aluminum with durable black powder coat paint
Mounting: Rack mounting for one or two units side-by-side optional (RK1, RK2)
Front Panel
Mute A/V: Toggles audio and video mute on/off, blanks all video and audio when active
Mute LED: Red LED lights when A/V is muted
Select: Up and down buttons select modes for front-panel programming
Channel: Up and down buttons select channels from stored tuning ring
Display: Red LED 3 digit, 7 segment alphanumeric display for channels and modes
Rear Panel
Power In: 2.1mm coaxial jack (inside center conductor positive), 350 mA maximum
11.5 to 16.5 VDC, 12 VDC typical (may be unregulated)
North American version includes UL/CSA listed wall power supply
RS-232 Control: DB-9 male connector, baud rates from 300 to 9600 baud
User selectable 300 to 19,200 (9600 default) baud, 8 data bits, no parity, 1 stop bit
Employs standard ASCII strings from any terminal program, PC, or control system
2 momentary closure inputs - Channel Up (Pin 4), Down (Pin 9), GND (Pin 5)
Antenna/Cable: ‘F’, female, 75 ohm impedance
Video Output: RCA female, NTSC composite, 75 ohm impedance, 1V peak-to-peak typical
Audio Outputs: 2 RCA female, mono 1K ohms, 20Hz to 20KHz,
0.5% maximum, 0.1% typical THD
Contemporary Research 4 232-MTA Mono TV Tuner

Contemporary Research 5 232-MTA Mono TV Tuner
Specifications
RF Tuner
Frequency Range: NTSC television 55.25 to 801.25 MHz, 62.5KHZ fine tune resolution
Maximum Input: Maximum Input: +20dBmV max, +10dBmV nominal*
Video Gain: ±5% maximum, 2% typical
Video Phase: ±3 degrees maximum, 2 degrees typical
*All tuners with firmware V3.7 to V4.1 made between Apr and Nov 2005 should be upgraded to new V4.3
(or higher) to ensure higher RF input level specs and best video performance.
Includes
12 VDC power supply, 400 mA min (North American shipments only)
Options
CC-232 RS-232 Control Cable (specify make and model)
RK1 Kit for mounting single unit in 19” rack, RK2 Kit for mounting two units side-by-side in 19” rack

Contemporary Research 6 232-MTA Mono TV Tuner
Troubleshooting
Symptom: Front-Panel Channel Up does not operate, advances one channel when powered
The RS-232 port has contact closures for Channel Up and Down on pins 4 and 9. Off-the shelf RS-232 control cables (such
as consumer null modem cables) that include those wires can lock up channel operation. If the problem clears up when you
unplug the RS-232 cable, use a cable with only 3 wires for GND, Transmit, and Receive.
Symptom: Problems with Cable Channels
There are three types cable channel systems, Cable, IRC, and HRC. While the Cable setting works for over 90% of
installations, there are a few cable systems set for IRC and HRC channel frequencies. Here’s how to tell which is which:
•IRC– Channels 5 and 6 are missing. Change to IRC and they should appear.
•HRC – None of the channels tune in. Change to HRC.
Front Panel Programming
To Enter a Front Panel Programming Mode:
1. Press and hold the Mute A/V button such that the red LED light above is lit (indicating Mute On).
2. Press Select Up.
3. Release all buttons, the 232-MTA will now be in the front panel programming mode.
4. The front panel display is dedicated to programming information display while in this mode.
5. Changes are saved in non-volatile memory as they are entered.
6. The Select up/down buttons scroll through programming modes 0 through 9 and 10+.
7. The Channel up/down buttons scroll through possible parameters for each mode.
To Exit the Front Panel Mode
Push and release the Mute All A/V button.
Modes 10 and above
When you select programming mode 10 and above, the Mode digit and decimal point will flash. For example, if
Mode 14 is selected, the display will show a flashing 4. - followed by the current parameter setting.
Modes 10 – 14 are identical to RS-232 Commands Q0 – Q4, included for RS-232 programming compatibility
with the 232-STS. In the 232-MTA all 10+ functions are fixed.

Contemporary Research 7 232-MTA Mono TV Tuner
Front Panel Programming Commands
Mode 0-9 Parameters Mode 10+ Parameters
RF Tune 0.0
0.1
0.2
0.3
CATV
Broadcast
HRC
IRC
Caption Type 10.0
10.1
10.2
Captioning off (fixed)
No function
No function
Baud Rate 1.1
1.2
1.3
1.4
1.5
1.6
1.7
300
600
1200
2400
4800
9600
19,200 (v3.5)
Caption Mode 11.1
11.2
11.3
11.4
11.X
No function (fixed)
No function
No function
No function
No function
Unit Number 2.1
2.2
2.3
2.x
One
Two
Three
Four – Nine (v3.5)
Video Detect 12.3 No function (fixed)
Not Used 3.0 AV Status 13.0 No AV status (fixed)
Panel Lockout 4.0
4.1
4.2
4.3
4.4
4.5
4.6
4.7
None
Channel up/dwn
Select up/dwn
Channel & select up/dwn
Mute A/V
Channel up/dwn & Mute A/V
Select up/dwn & Mute A/V
All
Label Mode 14.0
14.1
14.2
14.3
No function
No function
No function (default)
No function
Power-up
Volume 5.0
5.1 Restore to previous level Full volume
Firmware
Version 6.31 Ex: Version 3.1 - Press and hold
Channel Up, then Mute AV to
restore tuner to default settings
Audio Decode 7.0 Mono (fixed)
Bass Gain 8.8 0 db fixed
Treble Gain 9.4 0 db fixed

Contemporary Research 8 232-MTA Mono TV Tuner
RS-232 Control Protocol
Overview
The 232-MTA full duplex RS232 scheme enables a system programmer to control all TV Tuner functions as well
as monitor 3 groups of TV Tuner status. All commands are sent as ASCII strings. No delays between characters
or commands are required, as data is interrupt driven and buffered.
The 3 status groups are: Channel/Source Select, Audio Levels/Mode and Front Panel. The Mute A/V button-
function status from the 232-MTA front panel has been grouped with the Channel/Source for simplicity in the
most common modes of operation. Each of the groups has one ASCII status response string containing all of
the status data for that group. The current status string of a group is sent from the 232-MTA whenever a valid
command for that group is received by the 232-MTA RS-232 port or front panel. A group's status may be
requested at any time via the RS-232 port. Status of all 3 groups is sent at power up. The format of each
group's status response string remains the same always.
Up to nine 232-MTAs may be cabled together and addressed for individual control from a single RS-232 port.
Each 232-MTA is assigned a unique unit code (Front Panel Mode 2).
Communications parameters (Front Panel Mode 1) are 300 to 9600 baud, 8 data bits, No parity, and 1 stop bit.
Factory default is 9600 baud, Unit#1.
All settings are saved to NVRAM in the 232-MTA.
General protocol specifications
Characters in command strings to the 232-MTA are common ASCII keyboard characters. Command strings sent
to the 232-MTA begin with the ASCII > (greater than symbol) as an 'Attention' character and end with carriage
return - ASCII CR, Hex $0D, or keyboard Enter - as an 'End-of-command' character. Responses from the 232-
MTA begin with the ASCII < (less than symbol) as an 'Attention' character and end with a carriage return
followed by line feed an ASCII LF or Hex $0A as 'End-of-command' characters.
A carriage return is required at the end of each command and is assumed in all examples.
Command String Structure
[Attention] (Unit#) [Command] (Parameters) [Return]
Attention Single character (>) starts the string
Unit# The Unit# is expressed as an ASCII 0-9 when used in multiple tuner applications.
To address all units, use a Unit # of 0 (Zero – versions 4.0 and above)
Sending no unit number will default to Unit#1
Command A two-character command
Parameters Added attributes to some commands
Return A carriage return ends the command string, you may use ASCII CR, Hex $0D, or keyboard
‘Enter’ in programming. For simplicity, the programming examples in the manual will not show
the ‘CR’ – so remember, you’ll need to add it in your control code.
Command and Status Response
Commands can be sent back to back at any time without any delay. To allow for rapid, multiple commands,
status responses are intentionally delayed by about 125mS, sending the most current status in response to
control commands or user actions.

Contemporary Research 9 232-MTA Mono TV Tuner
General RS-232 Commands
Q Q-series commands Included for compatibility with 232-STS programming. As the
MTA does not have on-screen text or video detection, most
commands will have no affect in tuner operation.
Q0= Caption Mode Off (0-2) Sets captioning mode
0=Captioning off (fixed)
Q1= Captioning Type (1-8)
Turns on captioning type, no functionality in 232-MTA
1=Caption 1 (default)
2=Caption 2
3=Caption 3
4=Caption 4
5-8= Text 1-4
Q2= Video Loss Detection (0-3) Selects response when a loss of video signal is detected
3=No Function (fixed)
Q3= A/V Detect Status (0-3)
Example: ‘>Q3=1’ or ‘>Q31’
Enables/disables sending status response when Stereo/Mono or
Video Loss Detect changes. Only status operation is affected,
the functions continue to operate.
0=Disable Stereo/Mono detection (fixed)
1=Enable Stereo/Mono
2=Disable Stereo/Mono
3=Enable Stereo/Mono
Q4= Label Mode with Status (0-3)
0= No Function 1= No Function
2= No Function (fixed)
3= No Function
TR= Set Tune Ring (TR)
Example: ‘ >2TR=2,4,7-10’ Limits access to specified channels, 120 chars max
Stores unit#2 Tune Ring as 2,4,7,8,9,10
TT= Select tuned channel (0-126)
Example: ‘ >TT=28’
0=video mute, 255=video unmute*
126=External AV Inputs
Selects channel 28 only if 28 is present in current TR
TC= Force tuned channel (0-126)
Example: ‘ >TC=39’
0=video mute, 255=video unmute*
126=External AV Inputs
Selects channel 39 regardless of current TR
TP Set to previous channel Selects previous channel only if present in current TR
TU Tune channel up
Example: ‘ >3TU’ Selects next higher channel in stored Tune Ring Bumps Unit#3 tuned channel up one from available Tune Ring
TD Tune channel down Selects next lower channel in stored Tune Ring
XT Toggle Mute A/V Alternates Mute A/V on and off
XX Mute A/V off Turn A/V outputs on at previous level
XM Mute A/V on
Example: ‘>XM’ Mutes A/V outputs Mutes audio and video outputs
P0 Power Off Same as XM
P1 Power On Same as XX
PT Power Toggle Same as XT
* If the optional character generator is installed, Video Mute will display a blue screen, useful as a character
background. Without a CG, Video Mute will blank the video output. The Video Mute command does not mute
the audio.

Contemporary Research 10 232-MTA Mono TV Tuner
General RS-232 Commands
VU Ramp volume up No response
VD Ramp volume down No response
VL Ramps volume to level (0 – 63) No response
VX Volume Mute off Restores audio volume to previous level (full)
VV Stop volume ramp No response
VT Toggle Volume Mute Alternates audio mute on and off
VM Volume Mute on
Example: ‘ >VM’ Turns off audio outputs Mutes audio outputs
S0= Set tune mode 0=CATV
1=Broadcast
2=HRC
3=IRC
S4= Set front panel lockout mode 0=None
1=Channel
2=Select
3=Channel & Select
4=Mute A/V
5=Channel &Mute A/V
6=Select & Mute A/V
7=All
S5= Power-up volume 0=restore to previous level (always full)
1= Restore to full
S7= Set audio mode 0=Mono (fixed)
S8= Set bass gain level (8) 8= 0 db (fixed)
S9= Set treble gain level (4) 4= 0 db (fixed)
SS Request Front Panel status Unit sends “S” Front Panel status string
ST Request Channel status
Example: ‘>ST’ Unit sends “T” Channel/Source status string Returns Channel/Source status response string
SV Request A/V status Unit sends “V” Audio status string
A carriage return is required at the end of each command and is assumed in all examples. The ‘=’ sign for
parameters may be omitted if desired, though it is helpful for clarity in checking programming.