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HP82240A Hardware - TomC - 01-20-2014 06:56 PM
Is anyone familiar with the early variants of the 82240A Hardware?
Existing Documentation (the very fine T.Duell schematics) show a KA2183 device as the IR front end IC.
I've disassembled an 82240A and the IR front end is a TDA3047. I have the datasheet for this part, and am curious about the subsequent circuitry in the printer. It appears that the output of the TDA3047 connects to the base of a TO92pkg transistor. Before sliding down the circuit re-construction path, I would be curious is anyone else has traced this circuit and can share their findings.
Thanks,
TomC
RE: HP82240A Hardware - Tony Duell - 01-21-2014 09:34 AM
(01-20-2014 06:56 PM)TomC Wrote: Is anyone familiar with the early variants of the 82240A Hardware?
Existing Documentation (the very fine T.Duell schematics) show a KA2183 device as the IR front end IC.
I've disassembled an 82240A and the IR front end is a TDA3047. I have the datasheet for this part, and am curious about the subsequent circuitry in the printer. It appears that the output of the TDA3047 connects to the base of a TO92pkg transistor. Before sliding down the circuit re-construction path, I would be curious is anyone else has traced this circuit and can share their findings.
Thanks,
TomC
I have seen, but not for long enough to reverse-engineer it, a version of the printer using the TDA3047. It may be the -A uses that IC, the -B uses the KA2183.
The TDA3047, as I guess you've found, was a Philips IC. I have at least one data book that includes it. The transistor you mention is probably just a buffer/inverter.
RE: HP82240A Hardware - TomC - 01-21-2014 11:55 PM
Tony:
Thanks; given time, I may investigae how much of the remaining circuitry is similar to the KA2143 type design.
Regards,
Tomc