Repair an Atari 1020 Printer (30-60 mins)

Task: Repair an Atari 1020 Printer

Needed: 1020 printer, 3D printed gears

Time: 30-60 minutes

Introduction

I had an Epson dot matrix printer with my Atari 800 back in the day. It served me well but wasn’t that great with graphics and was only black and white. I recall drooling over the ads for color printers in Compute and other magazines but never got the chance to try them. So I jumped at the chance to purchase a new in box Atari 1020 plotter printer from an online seller for $35 this summer. I finally got a chance to open this beauty up and give it a spin.

Atari 1020 New In Box
Atari 1020 New In Box

I knew from reading online that many 1020s don’t work because of a cracked plastic gear that helps move the paper up and down. Without a functioning gear the plotter is unable to make accurate vertical lines. Fortunately, you can purchase 3D-printed replacement gears online from Shapeways. They currently sell them for $12 for a set of three. Here is a Youtube video on how to fix the 1020 with the new gear. Here is an Atari Age discussion on the subject. Here is the official Atari service manual for the 1020 although I didn’t find this all that useful. The service manual does say not to remove the pen cassette with the pens in it. I did this several times before reading this and hope I didn’t damage something. They repeat it twice with one time in bold so I guess it is important!

Atari 1020 Printer
Atari 1020 Printer

Instructions

Step one – Remove the top cover and the front panel

First, remove the dark plastic piece on top that covers the roll of paper. Turn the printer over and remove the two rubber feet on the front. The two on the back don’t need to be removed and are glued on. This will will reveal two screws. Remove these screws and the three others that are recessed. You will need a Phillips screwdriver for this. Then turn the printer over so it is right side up. The top white piece is connected to the black front piece by some plastic clasps. What I do is gently lift the back part of the white top piece. You will notice that it is connected to the black piece. At the same time slide both forward. Be gentle because the back piece is also connected to the main circuit board by some wires that are connected to the 1020 buttons. Once detached you should be able to tip both pieces up and away from unit thus exposing the innards of the system.

The Right Gear Assembly
The Right Gear Assembly

Step two – replace the gears

The photo above shows the right side gear assembly. There are three gears there that help control paper movement. The tiny one on the right is the one that needs to be replaced. Simply slide it off with your nail and slide on the replacement gear. The photo below shows my cracker gear.

Cracked Gear
Cracked Gear

I thought I was done and reassembled the printer only to discover that the cassette holding the ink pens wasn’t moving back and forth correctly. I stewed about this for a bit and then took the printer apart again and discovered there was another tiny cracker gear on the opposite side! This one controls the back and forth movement of the pens. This was not mentioned in the Youtube video or other online discussions about this. I replaced this one too and it worked! Note that this is a brand new printer that has never been used before. Both gears cracked solely because of age.

Step three – reassemble the case

The case goes back the same way you took it off. Make sure the tabs on the bottom of the black front piece stay parallel to the table and slide in below the circuit board. These tabs are where the screws below the rubber feet go to hold this part of the case on. It should all click into place pretty easily. Screw in the five screws and you are done.

Comments

To test my plotter I typed in the BASIC program below that is included in the 1020 manual that comes with the unit. This plots sine waves in blue, green, and red and then plots the axes in black.

BASIC code
BASIC code

Here is what the plot looks like on the 1020.

Sine Wave Plot
Sine Wave Plot

Note that you can get new pens and paper from Best Electronics. The pens of course are hit and miss and dry out easily. You can see that it my plot above. The red is weak.

Here is an Antic magazine article from 1986 about mastering the 1020. There are some sample BASIC programs included.