Canon Palmtronic F-6 scientific calculator from 1975 (kind of rare now?)
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05-07-2016, 02:37 PM
(This post was last modified: 05-07-2016 02:54 PM by jebem.)
Post: #1
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Canon Palmtronic F-6 scientific calculator from 1975 (kind of rare now?)
Found this one during my last trip to Porto city last week, when looking for vintage books in a old bookstore.
This machine uses a green Vacuum Fluorescent Display with 12 x 7-segment digits. However, two digits are reserved for minus signals and "memory in use" and "Error" annunciations. Another two digits are used for exponent. This leaves 8 digits for mantissa. After power on, the calculator shows a "0.^00". 2^5 (a^x) produces a good enough result of: 31.999974^00 ![]() ![]() The usual forensic check gives this result: 12.199423^00 (Degrees mode. 9 sin cos tan tan^1 cos^1 sin^1) ![]() Trying 1000 ln followed by e^x result in: 999.99964^00 And the classic 1 / 3 followed by * 3 gives a result of: 0.9999999^00 A honest result from this 1975 calculator. ![]() ![]() Pi internal constant stored value of: 3.1415926^00 Clearing the calculator and doing e^x twice results in: 2.7182804^00 ![]() ![]() Not as good as a HP-35 machine, but it is not that bad either. The case is very robust and well built and the keys have a good travel when pressed despite having no mechanical clicking, but at least they never fail to register. ![]() ![]() ![]() Jose Mesquita RadioMuseum.org member |
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05-07-2016, 02:52 PM
(This post was last modified: 05-07-2016 03:52 PM by jebem.)
Post: #2
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RE: Canon Palmtronic F-6 scientific calculator from 1975 (kind of rare now?)
A single screw holds the back cover that also have plastic notches to maintain structural rigidity.
![]() Does anyone understand what is written in this white label on the back cover? I suppose it is Japanese, and I saw another calculator picture in the Internet with the same label. Although my calculator is missing the English label that I can see in that other Internet picture. EDIT - Used ABBY Fine Reader and some Japanese text was recognized and later googled: CANON 保証書 = CANON Warranty card 197 年 月 日 = 197 year month day 内容は使用I兑明赛に驴鲛れてい = I use content wa ni donkey race against the next shark made me cry te い ??? Obviously the label printing is worn to the point that it is impossible now to be machine readable. ![]() Injection molded keys. ![]() ![]() ![]() Shielding spring connector detail. It connects the metal front plate to the machine PCB ground. ![]() The Hitachi HD3699 SoC processor is complemented by a DC-DC power supply converter to generate the required high voltage to illuminate the VFD. The PCA set includes: - The Processor/Power Supply/VFD main PCB, which in turn holds the Power Supply PCB; - The Keyboard PCB; All the three PCB's are soldered to each other by using single core wiring. I measured the current consumption using a 4.5V power supply. After power: 60mA All digits on: 82mA Calculating sin: 65mA. This translates to a power consumption of a minimum of 270mW and a maximum of 370mW, much less than the declared 0.6W value in the English back cover label (the one missing in my machine). ![]() The VFD terminals are clearly identified. Terminals "1" to "12" for the digits selection, then "a" to "g" and "dp" for the 7-segments plus decimal point selectors. The electrolytic capacitors have a working voltage of 50V. I didn't care to check them as the machine works flawlessly with a bright steady VFD light emission.. From the two power supply transistors, only one have a identification label, with "D467" (2SD467 NPN Si). The TDK transformer has a code of CD-1015, Japan. The date codes in the transistor and in the SoC processor is "5L". Visible in the picture is one broken black plastic pin that I couldn't find its original place. This machine was opened before by others, but apparently nothing was modified or repaired as all components solder joints looks tom be untouched. ![]() The 12 digit VFD is soldered to the Processor PCB. ![]() ![]() Jose Mesquita RadioMuseum.org member |
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05-07-2016, 04:24 PM
Post: #3
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RE: Canon Palmtronic F-6 scientific calculator from 1975 (kind of rare now?)
Thanks Jose
Another interesting read Cheers, Terje |
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05-08-2016, 12:44 AM
Post: #4
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RE: Canon Palmtronic F-6 scientific calculator from 1975 (kind of rare now?)
How very curious. I once had a Teal SR82 that gave that same 12.199423 forensic test result. Must have been the same chip.
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