OPTACON II USERS MANUAL ADDENDUM - R2B

Part number: R27403(print) R27404(braille)

The Optacon II model R2B has two new features and additional flexibility in adjusting the threshold.
Enhanced Threshold Refinement Capabilities: The R2B now supports more refinement in the threshold than with the R2A. Roughly speaking, the user will notice nearly twice as many adjustments can be made, for example, with serif print, as with the R2A. The conversion was changed from 40 My steps to 20 My steps.
Enhanced CRT use: The R2B allows variable CRT scanning frequency adjustments at 5 Hz intervals from 50-75 Hz to accommodate a broad range of monitors. This adjustment will improve or eliminate the pulsating image on the array that some monitors cause.
Hyperspeed Setting: This mode is useful for rapid ”scrub” scanning (used in- reading some foreign language characters' such as Chinese and Japanese. The effects will not be apparent in normal scanning.

HOW TO ADJUST THE CRT FREQUENCY

The user should be thoroughly familiar with the instructions for the CRT lens adjustment and use, and attempt to read the screen, with the Optacon II set on invert. If the image on the array has a pronounced pulsation, the model R2B can be adjusted to improve the pulsation to a steady, readable image, or totally eliminate the pulsation.
In invert mode, the frequency is changed each time the battery check button is pressed. Each depression of the battery check button will change the setting 5 Hz, within a range of 50-75 Hz. If the button is held in for longer than approximately 4 seconds, the frequency will cycle to the next setting. If the button remains depressed, the settings will run through the full cycle to 75 Hz.
Once the user has matched the frequencies and reduced or eliminated the pulsation, the button should be released. It will maintain this setting until the Optacon II is turned off or changed from invert to another mode, such as inverse video or normal, for reading ink print.
In the invert setting, the camera lamps remain on. Print can be read. The visual display, repeater mode and PC communications mode are also available. However, low battery detection is not available. The Optacon II would have to be returned to normal or inverse video mode to restore battery check operation.

HYPERSPEED SETTING

When the R2B is turned on with the battery check button depressed at the same time, the unit goes into a high speed mode which is useful for scanning characters such as in Chinese or Japanese in a rapid ”scrubbing” technique. Invert and inverse video modes are not available when this option is selected, even if the slide switch is changed to those positions. The visual display, repeater mode and PC communication modes are also not available. Low battery detection is available. To restore operation of visual display, repeater mode, PC communication and the range of reading modes, the Optacon II must be turned off and turned on again in the usual way, with only the on/off switch.

NOTE ON CHARGING THE BATTERY

For both the Optacon II models R2A and R2B, the battery does not charge on the unit. Batteries must be attached to the charger adaptor in order to be charged. Because the batteries are not fully charged when shipped, the user should charge each battery for fourteen hours before use.