HP82240A Internal view.

 

The HP82240A thermal printer can be opened by removing 6 screws. Four screws can be accessed by removing the rubber feet. The two other screws are located in the battery compartment. Take care, remove the print paper before opening the printer.

Picture of the HP82240A with removed top cover.

The printer module used, is build by Seiko, model MTP201-166. A single chip micro controller of the Toshiba TMP80C50AP series (HP part number 1820-4894) controls the printer. The received infrared signal is amplified and filtered by the TDA3047 of Philips.

 

The two pictures above show the PCB from both sides. On the left picture two more ICs are visible, which were hidden by the printer module on the top picture. These are the LB1246 printer driver and a MAX4193 DCDC Boost converter.

From this PCB a schematic has been extracted. This schematic can be downloaded here.

 

HP82240A internal related links:

• Schematic HP82240A by Tony Duell
• National museum of American History: HP 82240A Redeye B Printer, Engineering Model