9825A Arrival

Arrival

My HP 9825A arrived from France

Whether it works or not is unknown. It arrived in good but dusty state, but the tape drive is missing sadly enough.

The markings say it is a 9825A which is most probably correct; it has the System ROM cartridge that should no longer exist on the B.

Device pictures:

The 9825A as it arrived, dusty but complete apart from the tape drive. Tape holds the printer cover on.

The rear, with the four I/O slots empty and their covers still in place.

The front: the single-line LED display, the thermal printer at the right, and the tape slot at the left with nothing behind it.

Opening up showed the following:

Opened up. The RAM board sits across the top with the supply and its fan at the right; the cassette board is under the ribbon in the middle.

The keyboard and printer assembly:

The device has clearly been opened before and was left in a non operable state: screws were missing, the cables to the cassette were left dangerously loose, and the keyboard assembly was not connected.

Board overview

The topmost board is the RAM board. The slot above it is free and empty. The board has number 09825-66523 rev B, supposedly a 16KB RAM card:

The RAM board, 09825-66523 rev B: thirty TMS4060 dynamic RAMs and a row of drivers and multiplexers down the left.

After removal of the RAM board, by moving it to a 90% angle and then sliding it out of its hinges by moving it sideways, we see the cassette board:

The cassette board in place once the RAM board is out, hinged so it lifts away sideways.

A detailed picture of it after removal:

The cassette board out, 09825-66561 rev C, with the two 1820-0742 controllers at the right and the drive transistors on their heatsink.