Some HP parts inside - Printable Version +- HP Forums (https://www.hpmuseum.org/forum) +-- Forum: Not HP Calculators (/forum-7.html) +--- Forum: Not remotely HP Calculators (/forum-9.html) +--- Thread: Some HP parts inside (/thread-7242.html) |
Some HP parts inside - Maximilian Hohmann - 11-16-2016 07:54 PM Hello! Recently I found this piece here missing from my collection (Aristo Unilog, ca. 1975 - non RPN...): Unfortunately it does not work, even after replacing the slightly corroded battery connector. When moving the I/O switch, some digits of the display flash briefly, but this is all. But inside, there is a display from HP, something that I don't see very often in non-HP calculators: and some creative soldering as well (I have no idea what that potentiometer is needed for): Any idea about repairing this calculator is certainly appreciated! And in the same mail, I received this (inspired by the SR56 vs. HP25 thread http://www.hpmuseum.org/forum/thread-6989.html?highlight=SR56 ) calculator, which has been missing from my collection so far. Works perfectly, even the original (!) battery can still hold a charge - not something any of my HP-25s is capable of... As I own both now (the HP-25 and the SR56) I must say that the SR56 is overall the better calculator. But the Hp25 will always remain the one I would take to the solitary island! Regards Max RE: Some HP parts inside - HAL_2001 - 11-16-2016 09:18 PM Can't tell anything about SR56 but it's known for long that Ariosto's LED calculators featured HP display modules. RE: Some HP parts inside - Maximilian Hohmann - 11-16-2016 09:44 PM Hello! (11-16-2016 09:18 PM)HAL_2001 Wrote: ... but it's known for long that Ariosto's LED calculators featured HP display modules. Didn't know that! This one must be my first non-working Aristo calculator among 20 or so and therefore I never had to open one of them. RE: Some HP parts inside - PANAMATIK - 11-16-2016 11:30 PM (11-16-2016 07:54 PM)Maximilian Hohmann Wrote: Any idea about repairing this calculator is certainly appreciated! The chip on the right certainly is a driver for the 9 digits. A similar transistor array could replace it. The chip on the left could be replaced by an 28-pin PIC like 16F1518 running a calculator software. Not impossible if you have some time to spend! Bernhard RE: Some HP parts inside - Didier Lachieze - 11-16-2016 11:48 PM The two chips may be the same as the one used in the Aristo M 76, if you have a spare one you can look inside and check for similarities. RE: Some HP parts inside - damaltor - 11-17-2016 08:57 AM The right chip probably is a transistor array to drive the LEDs, as PANAMATIK already said. The potentiometer might set the brightness (= current flow) of the LEDs. |