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HP 82240: Difference between revisions
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==HP 82240A== | ==HP 82240A== | ||
Introduced in 1986, | Introduced in 1986, the HP 82240A implemented a modified Roman-8 character set, which HP continued to modify moving forward from the HP 18C with which it debuted. On later calculators a translation vector was used to map internal character codes to those used by the printer, such as the OLDPRT command on the [[HP 48]] series. | ||
Citing a desire to | Citing a desire to reduce costs, this variant was manufactured with single sided PCB which was a departure from standard HP practice at that point. A standby mode was implemented by the chipset, however standby power drain was rather high, draining a set of fresh batteries within 2 days if the unit was left powered on, thus HP recommended always having the printer connected to an external power supply. | ||
==HP 82240B== | ==HP 82240B== | ||
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The Seiko printhead uses two rubber rollers for paper ingest, which are glued to the main roller bar. This part can fail and run free due to age subjected to storing conditions. A tell-tale sign when this issue develops is the shrinking of line margin or persistent failure to feed. Replacing the entire printhead assembly is required in this case. | The Seiko printhead uses two rubber rollers for paper ingest, which are glued to the main roller bar. This part can fail and run free due to age subjected to storing conditions. A tell-tale sign when this issue develops is the shrinking of line margin or persistent failure to feed. Replacing the entire printhead assembly is required in this case. | ||
Leaving batteries in the printer for a extended period of time may lead to corrosion caused by battery leakage. Battery corrosion will most likely attack the contact tabs in the battery compartment, and is worse cases may eat away at traces on the PCB or get inside the darkness control potentiometer. The connection between the battery compartment contacts and the wires to the board are prone to failure due to corrosion. It is recommended to check this part for failure as the battery contacts also directly presses on the PCB from the underside, thus free floating power lead can cause short and circuit damage if allowed to float free. | |||
== Repair & Parts Availability == | == Repair & Parts Availability == | ||