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"Vintage Homebrew" section for the forum?

mountainking

Experienced Member
Joined
Jul 19, 2022
Messages
166
Location
Philadelphia
Perhaps there is just not enough interest in vintage homebrew pieces to warrant a section for them but I know there are some of you who go bananas for homebrew stuff like I do and would love to have a section in the forum for us admirers and owners of these pieces to share, archive, ask questions, pose questions about them, etc. After all, the early days if the microprocessor and the personal computer were all about the electronic hobbyists and their handcrafted machines. I guess the section would have to be for one offs rather than say, a homebrew Cosmac Elf, but maybe we could find some guidelines for things posted in this homebrew section that would allow for some homebrew versions of known projects from magazines and whatnot. That's something we would probably have to do some polling to decide upon.

So what do you all think? Is this something that the members would like to see? What's the alternative for those who would like to post something about the homebrew pieces from their collections? I'm not really a huge fan of the "what is this section" simply because of how it is set up, being that it is one long thread and trying to figure out what people are actually posting comments about is sometimes near impossible since many people don't bother to click the reply button when posting their comments, and besides, that section has it's own purpose, the "Homebrew" section wouldn't just be for those trying to figure out exactly what their homebrew gadget is. I know there is the "Other" section, which is great to have, but I kind of think of that more as a section for pieces made by less known companies or hard to categorize pieces made by actually companies (as opposed by hobbyists).

Thanks,
Alan
 

For those interested in all things home brew computing. Includes built from scratch and kit building systems. S-100, CP/M, Z-80, ECB, 6809, FLEX, and all the rest. Let's have fun!

It has almost no activity, but maybe that could change. Recently, I uncovered several vintage circuits, that I had built and I wanted to see them live again....so I interfaced them to an Arduino. Pretty tame stuff...and mostly things that would work of of the old PC LPT...SPO256, GI and TI sound chips...whatever I could get my hands on at the shack. Before then, simple IO boards for the TRS-80 M1 - 8212, 8255.

Never did actually home brew a complete system although I always admired what I would see and read in Kilobaud and Byte magazines.

I attached a zip of an .m4a sound file (plays fine in Windows Media) of the SPO256A-AL2. When I finished it and heard it for the first time, I laughed out loud....and then again some 30 years later :)
 

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For those interested in all things home brew computing. Includes built from scratch and kit building systems. S-100, CP/M, Z-80, ECB, 6809, FLEX, and all the rest. Let's have fun!

It has almost no activity, but maybe that could change. Recently, I uncovered several vintage circuits, that I had built and I wanted to see them live again....so I interfaced them to an Arduino. Pretty tame stuff...and mostly things that would work of of the old PC LPT...SPO256, GI and TI sound chips...whatever I could get my hands on at the shack. Before then, simple IO boards for the TRS-80 M1 - 8212, 8255.

Never did actually home brew a complete system although I always admired what I would see and read in Kilobaud and Byte magazines.

I attached a zip of an .m4a sound file (plays fine in Windows Media) of the SPO256A-AL2. When I finished it and heard it for the first time, I laughed out loud....and then again some 30 years later :)


For those interested in all things home brew computing. Includes built from scratch and kit building systems. S-100, CP/M, Z-80, ECB, 6809, FLEX, and all the rest. Let's have fun!

It has almost no activity, but maybe that could change. Recently, I uncovered several vintage circuits, that I had built and I wanted to see them live again....so I interfaced them to an Arduino. Pretty tame stuff...and mostly things that would work of of the old PC LPT...SPO256, GI and TI sound chips...whatever I could get my hands on at the shack. Before then, simple IO boards for the TRS-80 M1 - 8212, 8255.

Never did actually home brew a complete system although I always admired what I would see and read in Kilobaud and Byte magazines.

I attached a zip of an .m4a sound file (plays fine in Windows Media) of the SPO256A-AL2. When I finished it and heard it for the first time, I laughed out loud....and then again some 30 years later :)
I guess I was thinking more about adding another category to the GENRES section, but now I'm realizing that I don't completely understand exactly how the forum is organized, like what is the difference between the posts in the "genres" section and the posts in the "groups" section? Like if I had a homebrew 8085 computer project (I do) and I wanted to see if anyone could help me understand it's function better where would I post that question? I like how detailed the breakdown is for the forum but I keep finding myself wondering what section to post certain things in and what sections to look in for particular topics. Maybe I just need to spend more time looking things over.

I love the SPO256A-AL2 chip, I built this box using that ic that allows you to control the ic with toggle switches and free running clocks (ala Altair 8800 programming-minus the free running clocks), kind of hard to explain without going into detail but it's something I use in my electronics music rig to make strange vocal drones and random robot gibberish. Good stuff :) I have a stock pile of those ics along with a ton of other special function ics, many of them from RS and still in the original packaging- complex sound generators, top octave generators, voice recorders, rhythm generators, noise generators, etc, etc. Can't get enough of the stuff. I am working on designs for some of the ics, mostly music related gadgets.
 
There's a homebrew CPU webring that still has some interesting stuff.

Here's an example of a 16-bit serial CPU I could build this with parts from my hellbox.
I think you are misunderstanding what I am talking about, I actually thought your comment was a joke, that's why I responded to it the way I did. What I am referring to is historical pieces of homebrew electronics, those pieces that vintage computing collectors, like myself, collect, I'm not talking about modern day examples, that's why I specified "vintage homebrew". I also design and build a wide variety of electronic devices, that's how I make my living and it is my passion, but that's not why I joined this forum, there are plenty of other forums that are for modern day building.
 

For those interested in all things home brew computing. Includes built from scratch and kit building systems. S-100, CP/M, Z-80, ECB, 6809, FLEX, and all the rest. Let's have fun!

It has almost no activity, but maybe that could change. Recently, I uncovered several vintage circuits, that I had built and I wanted to see them live again....so I interfaced them to an Arduino. Pretty tame stuff...and mostly things that would work of of the old PC LPT...SPO256, GI and TI sound chips...whatever I could get my hands on at the shack. Before then, simple IO boards for the TRS-80 M1 - 8212, 8255.

Never did actually home brew a complete system although I always admired what I would see and read in Kilobaud and Byte magazines.

I attached a zip of an .m4a sound file (plays fine in Windows Media) of the SPO256A-AL2. When I finished it and heard it for the first time, I laughed out loud....and then again some 30 years later :)
I may have not been as clear as I thought I was being so just in case...I am talking about vintage computer based homebrew electronics, the kind of pieces that pop up on ebay and at estate sales, historical pieces from the 70s and early 80s that collectors like myself hunt for. I'm not talking about modern day electronics building that is based on early computer technology.
 
So, just to be clear, implementing an IBM 1401 in SSI would be outside of this topic? The homebrew CPUs I find to be fascinating--much more interesting that slapping some LSI together.
 
sand1cr.jpg

All kidding aside. I just wanted to point out that there was already a group here called "Home Brew Computing". In fact there is a new post there.today! It seems to be a pretty broad topic area. I attached that file because I thought it was funny and it was something I built in 1990 (still have the TurboC file) and resurrected it as described....because I no longer have an old IBM PC. I get that Home Brew Computing likely means different things to different people. It's all good.
 
I guess not. A better question is would a bit-slice CPU count, say, an NS IMP-16? What the heck, I'll allow it. Points extra for HB CPUs using Intel 3000 bitslice instead of AM2900.

I guess that I'd like to contribute a culture of "let's learn something" to supplement the "where do I plug it in" culture. There's so much to learn!

Take the example above--it's a complete CPU with no ALU--it's all TLU. After all, a CPU is little more than a state machine, right? Reminds me of the IBM 1620 CADET--first thing you did was load the addition and multiplication tables. Math was TLU on that machine.
 
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Sounds like a good idea!! I'll start off with a photo of my tiny Z-80. Two serial ports (one for console) and compact flash interface. Runs CP/M 2.2 with 16 "disk" drives of 8 MB each. I'm not much into games, but have a great interest in old compilers, so I've set mine up to run various versions of C, BASIC, Fortran, Pascal, and at least one version of PL/I. Using these compilers on older (2 or 4 MHz) hardware was painful, but this system runs at 20 MHz. These old compilers are quite usable at that clock speed! Oh, and it is so low power that it can be run from a USB port (via a 210x TTL serial to USB adapter).

Roger
 

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Here's another. It's a 68000 that runs at 20 MHz. It has 2 MB of SRAM and 1 MB of EEPROM. Two serial ports, one for the console, and a compact flash interface. Currently running CP/M 68k with sixteen "disk" drives of 8 MB each. There are native assemblers, C compilers, and BASIC, but I prefer to use the gcc toolchain set up to generate 68k code.

Sorry for the bodge in the photo. I was having trouble with spurious resets when getting it running, so I pulled the MCP-130 watchdog off the board. When I solved the problem (it wasn't the watchdog), I couldn't get the darn thing soldered back into the PCB. Not much space; hard to insert it.

Roger
 

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I did some of that home brew building back in the 1980s using the 8085 processor in a microcontroller. Actually four systems; I kept them separate for redundancy. (All use the same basic design, only the special purpose boards and memory chips determine whether the system is a speech unit or a heating system controller.) They took care of running a digital tone control system for lighting, etc; a speech synthesizer using the SPO-256 chip someone mentioned earlier, a controller that operates the heating / a/C system as well as an active solar heat system, and a phone interface that allowed me to call in and using DTMF tones control various functions. This was actually an early smart house back before such things were popular.

One thing not considered was how far technology would progress, and by integrating it into the house it was difficult to update or upgrade it. Fortunately they made things to last back then, and my systems are still in operation and working as designed back in the 1980s. By keeping a basic design and using plug-in cards for the processor, I/O, and special purpose cards I have been able to keep things running very well.and will continue to do so. (Today I could use the Arduino, Raspberry, or something else, but why re-invent the wheel when the system still works ?)
 
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