rackandboneman
  • Member for 5 years, 8 months
  • Last seen more than a week ago
Can I build a working(ish) vacuum tube byte?
1 votes

Have done so long ago (RS F/F for a demonstration), without introducing brutal voltages, have lost the schematics :( What I remember is that I used an E88CC (6DJ8), with either 12V or 24V as an ...

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What was the first personal computer to use surface mount components?
4 votes

The Epson HX20 from 1981 uses an LCD module which uses surface mount driver ICs.

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Was photographic film ever used for digital data storage?
19 votes

It IS used in at least two places even today: QR codes. There is the possibility of the print media carrying it having been prepared involving photographic methods. Digital sound in movie theaters, ...

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Where are the memory controllers for IBM 5150 or Altair 8800?
3 votes

The actual CPU bus (which would be called the "frontside bus" on 686-era designs) on the 8086, 80386, 68000 and similar CPUs IS more or less a memory bus. Typical peripheral chips (UARTs, floppy ...

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How to at least partially read damaged sectors of floppy disk?
2 votes

If the actual task at hand is recovering such data at any cost and effort, there is still the possibility of directly recording the read head signal on some recording and visualization device, eg a ...

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What are best techniques for repairing a chemically damaged PCB?
Accepted answer
5 votes

Restoring to an as-new look is likely not possible with the damage described. Most western PCBs used for computers use solder mask (the green stuff) over the traces - if corrosion happened UNDER the ...

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Why did some early CPUs use external math chips?
9 votes

Many small CPUs available and used today for embedded designs do not have an onboard floating point unit - most of the AVR and PIC series, MCS51, some ARM ... 8 bit single-chip microprocessors were ...

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Why did CPU designers in the 70s prioritize reducing pin count?
10 votes

Lead lengths inside a 64 pin package slowly get problematic, even at 1970s speeds. Even a digital system working at a few MHz requires you to pay attention to things like routing signal lines close ...

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What PC "Clone" technology standards were introduced by clone manufacturers?
17 votes

The first PC compatible 80386 machine was introduced by Compaq. The VESA Local Bus, and similar short-lived/proprietary local bus standards, were also not introduced by IBM. Most graphics cards that ...

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Why did the IBM PC need a sound card?
4 votes

One major thing the builtin sound hardware lacked was any facility to input/record (but so did the very first IBM soundcard, which was more or less a Yamaha FB-01 on an ISA card).

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Is DOS being shipped with or as an installed OS?
0 votes

In some cases, free (whether open source or just available legally with no payment) operating systems are installed on "blank" hardware to satisfy requirements in the licensing agreements of the OS ...

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Why are punch card readers no longer in use?
2 votes

If one wants to use paper as a backup medium, there is always the option of using an OCR friendly font and printing the data - in plaintext or using a binary-safe encoding like base64. You will still ...

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Was there ever any reason to wait 30 seconds to restart a c.1995 PC?
54 votes

The reset button does not affect the power supply at all. It sends a reset signal to the CPU (and probably the bus). Some power supply designs indeed will wear quicker if quickly switched on and off, ...

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Can a HiFi speaker erase a floppy disk?
2 votes

A loudspeaker has two magnets interacting: One big, usually permanent one (two-electromagnet seems to have gone out of fashion in prewar times), and an electromagnet (the voice coil). The permanent ...

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Why were floppy drives not any faster?
Accepted answer
43 votes

As you mentioned, speed was considered sufficient for the typical applications at the time they were introduced. Also, any significant rotational speed increase would have meant: More complex data ...

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Run 8086 programs in dos using simple os other than any special software
4 votes

Assuming your question is about working with 8086 assembly language programs, without using third party software. Look at the DEBUG.EXE program that is part of all practical MS-DOS distributions -it ...

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What makes a floppy disk bootable?
1 votes

Addon, answering an aspect explicitly asked about in the question. A "dd image" of a complete floppy disk, unless dd is used with special (skip/count) parameters, will always carry the parts that ...

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Was there ever a kilowatt workstation?
Accepted answer
7 votes

The SGI Onyx and related machines were made in a "deskside" version. Let us look at the specifications from this manual ... https://techpubs.jurassic.nl/library/manuals/1000/007-1733-070/pdf/007-...

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How to get Windows XP to detect a DB-15 gameport joystick?
7 votes

The DA-15 Joystick port (BTW, not to be confused with the AUI ethernet connector, which is also a DA-15 with additional locking hardware!) has no standardized provision to detect what is connected to ...

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Why did Commodore sell CPUs to its competitors?
16 votes

The 6502 has been used in huge volumes in markets that commodore never cared about competing in much - terminals for large-scale professional computing, printers and plotters (which they mostly bought ...

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How were interpreters loaded into computers?
1 votes

Any machine-code program that does not rely on routines supplied by a full-on operating system can be "installed directly to the hardware" just as it is done with the BIOS: The machine code is written ...

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Why did blanking of screen on C64 SAM enable better quality speech synthesis?
1 votes

As mentioned above, timing distortion, especially if your CPU is heavily involved in live video generation as it is in "home computer" style machines, is an issue. Also, such designs did not tend to ...

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The baud rate of which serial card does the "stty" command returns in UNIX V7?
2 votes

Logic suggests it is only the "local" (host) side affected. Any method to change the baudrate of a real physical terminal via something sent down the serial line itself would be highly vendor ...

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Primary manufacturers of picture tubes for early monitors
Accepted answer
4 votes

I know links as answers are frowned upon. But this official document called "Color Picture Tubes from Canada, Japan, the Republic of Korea, and Singapore" by an US commission has more on both US and ...

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Graphics chips in 1980
5 votes

It likely was not the graphics chips (or for that matter complexity of a solution built from non application specific chips) that limited practical high resolutions at a price point - you still need a ...

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When did the tower form factor appear and when did it become popular?
3 votes

PC specific, ignoring non-PC systems here. Remembering early-90s systems, 286 machines were mostly built in the "Baby-AT" form factor. Sometimes you still saw new 286/rarely 386 builds in the full-...

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Reading the program on an EPROM chip
1 votes

Half OT, but whatever: Once you built this breadboard circuit, try to get your hand on some 2816/2864/... chips (not 28Fxxx flash!) - these EEPROMs share a pinout with the 27xx EPROMs and are easy ...

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Why isn't the approach to lower power CPUs guided by design rather than accident?
Accepted answer
2 votes

Design is one factor determining the actual power use of your device - the other is the semiconductor process used and its tolerances and variations over the product lifecycle. Especially with ...

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Serial Receipt Printer Garbage
Accepted answer
7 votes

If the printer is offering an actual RS232 port, this should be identifiable by there being an RS232 level converter IC near the connector on its logic board: Usually, there will be a DS232/MAX232 or ...

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Emulators running on 8-bit personal computers
2 votes

To put the possibility in perspective, look at the much more modern (now defunct due to non-availability of the SoC) Flea86 project, which sufficiently emulated a PC/XT to drive an ISA graphics card ...

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