Pen Plotters Selection:
|Name: 7225 Flatbed Plotter|
|Product Number: 7225A|
|Division: San Diego|
|Ad: Click to see|
|Original Price: $1850|
|Catalog Reference: 1979, P. 256|
The 7225A was unremarkable in most respects. It was a single-pen (uncapped) flatbed plotter. Its design goals were to reduce costs and to improve reliability without sacrificing line quality. By using lower cost electronic components and linear stepper motors, manufacturing assembly and test times were reduced by a factor of six compared to other similar products. The product also incorporated improvements in electrostatic media holding technology.
The 7225A was obsoleted in November of 1982.
Click here to view CuriousMarc's video of an HP-85 driving a 7225 serial interface plotter.
7225s can suffer from a number of ailments. It is relatively common for the paper platen to separate from its base over time. This can be reattached with glue. Some 7225 models have filtered plugs for the AC input cord. The capacitors in these plugs have a tendency to fail with age and smoke out. The plugs are easy to replace with new ones. The springs under the control panel buttons are made of bent metal, rather than coils. These springs can rust and break over time. The power supply on one of the two 7225s we have at the museum has failed.
The most intriguing problem that afflicts almost all 7225s to some degree is travel stiffness along the Y-axis arm. This travel stiffness occurs near the bottom of the Y-axis arm (with free travel occuring near the top of the arm). The stiffness is not due to mechanical tolerances. The museum has no experience with the motor/rail design used by the 7225A and would be interested in hearing from anyone with relevant knowledge.^ TOP
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