JED Microprocessors Pty Ltd. 173 Boronia Rd Boronia 3155, Vic, Australia. +61 (03) 9762 3588    JED Home   Main JED projector control page, distributor list, etc  The T440 is a lower cost RS232 remote controller for LCD and DLP video and data projectors, LCD and Plasma flat panels, for budget installations in lecture theatres, classrooms, churches or conference rooms.

Alternatively, the controller and front assembly can be mounted on a black or white Clipsal 2000 base block, and can be wall mounted near the operator's position. 

A 45 degree white or black metal case is also available (see below)

The T440 has an attractive white, or black, smooth escutcheon surrounding it, to give an overall size of 110mm by 70mm. This covers the screw holes and can be mounted into a lectern or desk at a convenient point for the speaker to control video and data projector operations. As an option, just the adhesive backed keyboard and electronics board can be supplied without a Clipsal plate, to allow installers to mount the system on their own panel to match the decor of media control desks or wall plates in boardrooms, etc.

The T440 is wired back to the LCD projector via an RS232 data cable, needing only three wires (TX, RX and Ground). (A connection for a fourth wire with 9 volts on it is available as a CTS or DTR line HIGH to the projector to enable RS232 transmission, as some projectors expect this input to be HIGH before allowing transmission.) 

The control codes for different projectors are programmed into the T440 controller, and the projector family needed for a particular installation is selected on the rotary switches on the back. Keyboard type and options are selected on other switches on tha back.

Keyboards

The normal keyboard background colour is off-white, or "beige", as the photos show. Other colours and key layouts can be produced if a quantity are needed.

The T440 has a choice of keyboard labels ... many different layouts can be accomodated, with up to eight keys, and up to four LEDs (always in the positions shown.)

In some layouts, a separate On and Off key is provided, having green and a red LEDs as state indictors. During warmup the green On LED flashes. During cooldown, the red Off LED flashes. A channel LED comes on steady to indicate the channel to start with after warm-up. (This can be preselected by pressing other buttons)

Audio mute function

Pressing both Volume keys together mutes the sound and picture, on most projectors (some don't have support for this).
(Either yellow key, or the current channel key, restores the picture/sound).

The audio keys auto Increment/Decrement the audio level if a yellow key is held down. (Times are programmable.)

Keyboards with combined Channel function and Power On

In layouts which combine a channel button with the "On" function, the selected channel LED flashes during warmup. (The channel can still be changed during warmup.)

On some layouts, a "portrait" or vertical format can be chosen.

New TV/LCD keyboard

6-Key with three channels, Landscape	6-key with three channels, Portrait	TV/LCD/Plasma 8-Key controller keyboard (artwork)

Audio control

The control of audio level is usually done in the projector, and audio control signals are sent to the projector along with the video source and power control signals.

This assumes:

1. The projector has enough, and appropriate, audio input connectors for the video & computer channels to be used;
2. There is a line level audio output connector on the projector to drive the room amplifier and speakers; and
3. The projector actually controls the audio level of the output audio via RS232 (not just the projector's internal tiny speakers).

If a T461 audio rack is installed, it is controlled with a second serial port on the T440, and the T461 selects and controls the audio levels in step with "source select" signals sent to the video projector.

T461 audio attenuator/mixer

The T461 is a 1RU high 19-inch rack mount unit, with four line level stereo RCA pairs as inputs and one line level RCA pair as output. It has an  RS232 input and a 240 volt IEC mains connector. A 12-volt power output can power the T440. All connections are on the rear, and on the front are four LED channel indicators and screw-driver adjustable prescaler trim pots.

(This photo has T460s rather than T440s.)

Application

They need to power up the projector, select a source, run a video or computer presentation or demonstrate some other program, or display a feed from a document or microscope camera on the video screen, and then close the system down again. Contrast the four or six buttons on this unit with the 20 or 30 on some IR remote controls, each one different from room to room. This unit is identical from room to room, even with a mix of different projectors.

And when the show is over, T440 controller does not walk out the door in the lecturer's pocket like IR remote controllers often do!

Operation

1. Turn the system on by pressing the ON key. or a combined Video / On or Computer / On  or TV / On key . The projector starts, and a green LED blinks for the warm-up time. At this point the channel LED shows the last used signal source;
   
 
2. If a different source is needed, press an alternate source key until the desired source LED turns on;
   
 
3. When running, use the yellow VOLUME UP and VOLUME DOWN keys to set the desired audio level for that source. In absolute source volume systems, or, in systems using the JED T461 audio attenuator/mixer, the last used setting is remembered channel by channel and recalled when that source is re-selected. In “incremental” systems, the projector usually displays the varying audio level on the screen. Pressing both volume keys together causes a picture/sound mute;
   
   (In some alternate layouts, other functions are performed by the yellow keys, eg control “picture/sound mute”, or "picture freeze", if selected);
   
 
4. When the show is finished, pressing the OFF key ramps the audio down and turns off the projector. The red Off LED flashes for the cooldown period.
   
   The proper warm-up and cool-down and lockout times are set for the projector, until the unit goes to standby mode for the next cycle. (Red LED on non-flashing.)
   
   
5. Pressing the OFF key in the standby mode will re-poll the projector, and if the projector communications is responding, the red LED with blink three times.

PIR input for automatic closedown

Installation

1. Mount the T440 in or on a panel or Clipsal 2000 base on the wall. A cut-out drawing is supplied in the user manual. All wiring to the T440 is via plug and socket Phoenix connectors to the rear, and the wiring is into screw terminals, so no soldering is needed at this end. Plugs are provided with the unit, and wires are simply stripped and fixed into plug holes with grub screws. Changeover of a unit is pull-out/plug-in, and just needs a screwdriver for the mounting screws;
   
 
2. In the simplest case, the units needs a 9 to 25 volt DC plug pack or bench supply connected to one plug (labelled +V, Gnd). Current consumption is under 25mA. A 12 volt plug pack is supplied with units in Australia or new Zealand.
 
3. Connect a three wire RS232 cable (TX, RX Ground) from the plug labelled "Projector". Wire the other end of the cable to the projector RS232 control socket input. (A fourth line, CTS is an RS232 output, always HIGH, available for some projectors which need a CTS or DTR input at a logic "1");
   
 
4. If the JED T461 remote audio attenuator/mixer is needed, the connections between the T440 and T461 consist of three more RS232 lines (TX, RX and Ground) from the "Second RS232" connector to the rear of the T461, and power to the T440;
   
 
5. Wire the PIR into the T440 3-pin plug, or jumper these two contacts if no PIR used, so the timer function operates.

Setup

Reprogramming

Downloads

Angle mounting bracket

T465 Microphone and radio input line mixer

The left hand volume control is for the microphone input, and this is added to both channels equally. Rear preset switches allows the gain for the microphone channel to be preset in 6 steps of 10dB (0 to 50db). Inputs can be balanced or unbalanced (a switch on the back can ground one channel). Phantom power at 12 volts can be connected to the balanced microphone inputs to power a phantom-powered microphone preamplifier. Another switch controls a base-cut switch to reduce breath pops, etc.

It also takes a radio microphone input, and mixes it to both channels as well, via the right-hand volume control. 

The advantage of such an audio control panel is that the lecturer does not need access to mic volume controls on the audio amplifier (which might be across the room in a secure rack), and can control the roving mic channel from the lectern as well.

A rear stereo log pot allows the T461/projector input level to be preset. (This signal level is adjustable via the "volume" buttons on the T440.)

A second stereo output is available to feed a cassette tape recorder to allow taping of lectures. 

A photo is available here: T465.jpg

A  data sheet is available for download: T465DS1.pdf

What's inside the T440

How to buy the T440

Distributors worldwide ... if you are interested in the T440, call/email Ed Schoell at +61 (0) 3 9762 3588 to be added to the list and to our direct mail distributor recommendations: eschoel@jedmicro.com.au