Vintage Calculator Repair - 1972 Hitachi KK561 - Part 2 - Fixed

Описание: In the last video we looked at the Hitachi KK561 calculator, which wasn't working at the time, and eventually traced the fault to a faulty HD3233P chip that drives the display. Now, after a fairly long wait, a random circuit board has arrived, complete with some spare chips, so we'll install the replacement chip and then demonstrate the now fully functional 1972 Hitachi KK561 calculator, not forgetting the unanswered question, what happens if you divide by zero?

You can see the first video here:
   • Vintage Calculator Repair - 1972 Hitachi K...  

Start 00:00
Replacement Chip 00:16
First Test 01:47
VFD Tubes 02:50
Decimal Places 03:41
Sigma 04:37
Constant 06:03
Sigma & Constant 06:38
Rounding 07:42
Squaring and Negative Numbers 08:30
Register Reverse 09:17
Overflow 10:15
Divide by Zero 10:29
Summary 11:07
Outro 11:40

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Outro Music
"As Yet Untitled"
by GrumpyTim (available to download from GrumpyTim's Bandcamp page)
https://grumpytim.bandcamp.com/

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