"Get back to work, you muppets."

Renting a new VPS, Retiring this blog, Moving Everything Over

Well, I suppose I finally acted on one of my day dreams that I wrote about on this blog.

I am not happy that this blog uses non-free scripts, so I thought I would backup everything here on Bootlicker and set up a new site. A comrade of mine recommended Hugo go to me, a static site generation platform written in Golang. They also recommended that I rent a Virtual Private Server and manually configure it to host HTTP.

So I did all that. I rented the VPS, and I configured it so that it is very secure — it only uses 4096 SSH keys, and it has a very strong firewall now. There is much more information and support for configuring and taking control of a VPS than there is in fixing a WordPress installation.

I have also been having terrible perfomance on this web server. the .htaccess file (Apache… :/) for this site has become corrupted several times over the last week. It has completely disabled my ability to use and maintain this blog, so I guess the terrible performance of this server finally pushed me over the edge to setting up my own VPS.

The great this about this new VPS is that I will now be able to unify all my old blogs:

  • The Mondegreen (
  • Come See the Duck (
  • JumpnShoot 9000 (
  • This one, Bootlicker (

I think I even have a LiveJournal… but that one got backed up and published onto the Mondegreen.

Anyway, exciting times. Finally I will have actually parked onto a server, and not just a simple web redirect.

Research for CMOS Discrete Transistor Computer #1

So CMOS stands for circuits with Complementary Metal Oxide Silicon construction. This contrasts with NMOS and PMOS circuits. CMOS circuits use both PMOS and NMOS MOSFET transistors.

CMOS circuits are able to have quite a large portion of their circuits non-conducting, due to their use of both NMOS and PMOS transistors.

I have chosen to build this discrete transistor computer using a CMOS design. This is because there is much more documentation of CMOS logic than Diode-Transistor logic. My last two attempts at building a discrete transistor computer used DTL, and it was frustrating to find information on how best to construct DTL designs.

It may be that DTL is cheaper. In which case I will ditch CMOS and go back to DTL. I will look at the plans of the PDP-8 and PDP-11 to understand their DTL design.

Anyway, the first issue you have with making a CMOS computer is to make sure you can actually turn on your transistors. I have chosen 5V as my logic level, which means we have to make sure the Drain Current [I(d)] is quite large when the Gate-to-Source voltage is HIGH.

We need to make sure the MOSFET is as close to saturation (full conduction between Source and Drain) as possible.

Transistors can be in three modes. Cutoff, Linear Region, and Saturation. If you want to use a transistor as an amplifier, you will use it in the LINEAR region, the region best for analogue circuits – the Drain current I(d) will vary linearly with the voltage of the gate.

The equations for this are:
V(gs) > V(th); and

V(ds) < (Vgs-Vth).

So the Gate voltage must be higher than the threshold voltage, and the amount of volts the Gate is above the Threshold must be higher than the Drain-to-Source voltage.

This tells us how to turn a transistor ON, how to get it out of the cutoff region.

What it doesn’t tell us is how to completely saturate a transistor. We want to either turn off (cutoff) or turn on (saturate) the transistor. This will correspond to the binary logic states of 0 and 1.

The fastest way to find out how to saturate a MOSFET is to look at its transfer function in its datasheet. The property to look for is to see how much more current the MOSFET will conduct through the Drain as the Gate voltage increases.

If the graph of the Drain current looks flat in the region of 5V, it is no longer in the linear mode of operation at that Gate voltage.

Here is a list of the cheapest and most suitable logic level MOSFETS I can find:

At V(gs) = 5V, this MOSFET is just at the end of the linear region. May be suitable.

5V V(gs) will see this transistor conducting more than 100A – it may even be harmful to the transistor – check the Max V(gs).

Just checked the datasheet. The max V(gs) ia 15V. This transistor is probably very suitable.

This is actually the HUFA76429D3. Same as above. The max V(gs) is 16V. This may be a very suitable component.

This transistor will have a drain current of more than 10A at V(gs) 5V, even though it won’t be fully saturated. This component may be suitable.

The 640N still has 5V V(gs) in the end of the linear region, but it will still be conducting more than an ampere at this stage, so it may be suitable.

5V is well and truly in the satutation region of this MOSFET, the 3710. The Drain current will not be increasing much more with any more Gate voltage. Bear in mind the logarithmic scale.

A List of Discrete Transistor Computers

All Your Transistors Are Belong to Us (Hackaday.IO Link)


ED-64 (Hackaday.IO Link)


Digital Camera

The Cardboard Computer (Hackaday.IO Link)


Yet Another Discrete Computer With Silicon Transistors (Hackaday.IO Link)

Megaprocessor (Website Link)

Dieter’s MT15 (Website Link)

4 bit Discrete Transistor Computer (Hackaday.IO Link)

Johnny’s Homebrew Discrete DTL 8080 Clone (Website Link)


Another Idea

Computers that only boot off removable media.

It’s genius. You can’t hack a computer that has a complete air-gap between its OS and its hardware while it is off.


Computers that completely turn off, and don’t rely on soft-starting.

Turn Off Your Browser’s JavaScript

If you do this your internet will be so much faster.

I swear: the internet is so much slower and bloated because of JavaScript. It is stupid. When Australia’s internet is already crumbling and completely non-functional, why do we need all this client-side processing slowing things down?

Get rid of non-free scripts.


So it turns out our ADSL in this house is so bad we get logged out of our Xbox Live account. This prevents us from being able to use VLC, to watch MKV files – which many dramas are encoded in.

It makes me think – what if we set up a sneakernet? A sneakernet is a physical delivery of digital data. You might walk a USB stick to your friend’s house. You might download a library of movies from your friend onto a hard drive and drive it home.

It has been proven that carrier pigeons are faster than ADSL internet. I bet they’re faster in terms of bandwidth than the Australian NBN. The internet in Australia is so bad, I think we may have to resort to a sneakernet in order to keep information flowing.

What do you think?

Project Ideas

I have a lot of project ideas. I’ve been coming up with them faster than I can write them down. I’m sitting here at the bus stop with 10 minutes to kill, so I figured I’d finally make the time to write all these things down.

Some of these ideas are simple, and may only take a couple months to finish, whereas some projects may take a very very long time to achieve. Here we go:

  • Develop a philosophy of practical computing. Simple, repairable computers that do not spy, are built with open hardware, and are easy to understand and repair. You do not need a lot of transistors to do word processing, for instance. Usenet and Bulletin Board Systems are sufficient for most social communication. The World Wide Web and HTTP are terrible.
  • Develop a practical 8 or 16 bit computer that is useful and easy to repair.
  • Make a Commane Line Interface mobile phone.
  • Investigate how to make your own internet network (Satellite? HAM radio? Some other radio spectrum? Use the voice mobile phone network and use audio and encrypt?)
  • Contribute to the GNU search/construction of a micro kernel.
  • Buy a Commodore 64, or similar 8 bit computer, and refurbish
  • Develop own C64 software compatible micro computer out of TTL chips
  • Develop discrete transistor computer
  • Set up computer recycling service
  • Learn Ada
  • Develop a new NNTP program with all the modern security trappings
  • Learn about jobd
  • If not possible to make C64 hardware compatible TTL chip computer, write an emulator for it
  • Learn how to fabricate my own integrated circuits
  • Manufacture my own transistors
  • Finish my PhD
  • Get a job as an academic
  • Get a car
  • Relearn Japanese, and learn Spanish and Mandarin
  • Finish my Atari 2600 game
  • Buy the Shadowrun Core Rulebook
  • Build my own laptop with a Single Board Computer
  • Finish my Distraction Free Writing Machine project
  • Build a relay computer, and program it to play Noughts and Crosses, maybe other games
  • Finish learning about transistor amplifiers
  • Build a RISC V CPU with an FPGA
  • Investigate that project that runs BSD on a PIC microcontroller
  • Buy a mechanical keyboard
  • Buy a CRT monitor
  • Write up how to substantially get a KDE install of arch linux working (sound card, networking, USB permissions)

That is all I can think of!

Ockham’s Razor for Transistors

For most tasks, we only really need an 8 or 16 bit microcomputer. The 6502 or the 68k is sufficient. 64KB to 4MB RAM is enough. The amazing thing about the Apple II and TTL was that it encouraged hacking and modification. Where are the micros able to be repaired now?

Thru hole soldering is easy to repair. BASIC was an awesome language for computer literacy. Usenet and BBS systems were way more democratic protocols for the internet.

Kilobyte programs were easy to disassemble and reverse engineer in machine language.

Also: no MMU, no spectre.

8 bit games had better metaphors and themes. A small team could still make them.

6502, 68k assembly is so beautiful and easy to write. They’re hand designed to help optimise memory and performance.

Who writes assembly for the micro now? You can’t.

You don’t need a $2k PC.

Barnaby Joyce