Summary

Standard definition widescreen monitor from Ikegami. Supports 240p/480i only. Has modes for 16:9 full and 4:3 letterbox. Primary use case is to display anamorphic 16:9 content. Tube is made by Toshiba and has the hallmark purplish-hue of Microfilter.

You can find a list of games that support anamorphic 16:9 here.

Manuals

• Service Manual
• Specification Sheet

Toshiba Microfilter Technology

This CRT uses Microfilter, a technology innovation by Toshiba that aimed to optimize both brightness and contrast without darkening the glass with tint.

Conventionally, most tubes have a dark tint layer in the glass to reduce the amount of light reflection or absorption of the glass, thereby increasing contrast performance - a trade that costs an average 30% loss of overall brightness in all ambient light conditions (including near-darkness). In comparison, clear glass on a tube has the advantage of maximum brightness emission - but at a huge loss of contrast in normal ambient light conditions due to increased reflection. Typically you'll only find clear glass on professional broadcast monitors (aka BVM) that are intended to be used in near-darkness where ambient light is not an concern.

Microfilter aimed to be the best of both worlds by achieving the necessary amount of ambient light filtering at a per-phosphor (micro) level without sacrificing brightness, while still providing the vivid contrast you could typically only expect from a dark-tinted lower-brightness tube. On a Microfilter tube, the glass itself remains clear for maximum light transmission, while still taking a darkened grey-purple appearance from a combination of both the AR coatings and Microfilter over the phosphors.

You can learn more about Microfilter in our full article.

Notes

Repair log

The power supply is adapted from the one of the TM24-17, with several small changes:

• output voltages are different: the silk screen has those for the 24", so refer to the service manual for the correct voltages of each test point.
• a trace has been manually cut and there is a wire bridge to the test point. See image power_board_bottom1.jpeg and power_board_bottom1_zoom.jpeg .
• a few components are missing or with values slightly different from the service manual

There are also some errors to be aware of:

• C19 has the wrong polarity in the service manual
• C32 has the wrong polarity on the silk screen

The fact that the power board was manually modified from another model is an indication that the production volumes of this monitor were very low.

Also the power board is pushed to the limits of the design: if the image is set too wide is very simple to make the power regulation unstable and trip the overcurrent protection when the brightness or raster size changes slightly.