The following components in Teletypewriters TT-47A/UG, TT-48A/UG, TT-69A/UG, and
TT-70A/UG differ from the corresponding ones in Teletypewriters TT-47/UG, TT-48/UG,
TT-69/UG and TT-70/UG.
(1) POWER DISTRIBUTION PANEL SB-154A/UG.- This component differs from SB-154/UG principally in that the connectors on the ends of the cables leading to the Keyboard and to the Automatic Typer have been changed. Therefore, it cannot be connected to the
MX-1114/UG Keyboard or to the MX-1115/UG Automatic Typer.
{2) KEYBOARD MX-1114A/UG.-This component differs from MX-1114/UG in several respects. It has a 20 terminal receptacle, whereas the
MX-1114/UG has a 14 terminal receptacle. Thus this component cannot be connected to a
SB-154/UG Power Distribution Panel. The spring powered throwout mechanism has been removed from the
MX-1114A/UG clutch. The position of the repeat key has been shifted to the right and the repeat mechanism has been redesigned. Several changes have also been made in the adjustments, and in the lubricating procedure.
(3) AUTOMATIC TYPER MX-1115A/UG .- This component differs from MX-1115/UG in several major respects and in numerous minor details. Since the changes in adjustments are many and varied, the adjustment requirements specified in Section 7 of this instruction book must be adhered to. The
MX-1115A/UG has a 20 terminal receptacle, whereas the MX-1115/UG has a 14 terminal receptacle. Consequently, this component cannot be connected to a
SB-154/UG Power Distribution Panel. The MX-1115A/UG has a new main shaft, and a redesigned selector mechanism with an improved method for orienting the range finder. The ribbon feed mechanisms have been revised to include an improved slack take up feature and improved feed pawl adjustment. The range of the automatic carriage return-line feed arm on the spacing drum has been increased to accommodate a maximum of 85 characters per line. Also, several ratchet teeth have been removed from the spacing drum to prevent over spacing in the event of spacing clutch stop failure or spacing suppression failure. Changes in the lubrication procedure are few.