Reliving my (computer) childhood.
frank freedman
Posts: 1,977
Wandering through some old threads while working on a small wire wrap project got me thinking back to my early days of computing. Like IMSAI 8080 days. I used to use a program called Wiremaster to create wirelists for wrapping my Z80 projects (anyone play with the three voltage dynamic ram? The Z80 made using dynamic almost as easy as static.) and while (#%&$^$*) the IMSAI is long gone, I still have that particular package in the garage somewhere. Deeply somewhere. So, a bit of googling (yep, google really can be your friend) and I found not only a number of CP/M emulators including one that even gives you a working IMSAI, but Wiremaster as well. And it works very well. Just have to either remember the source syntax or take a deeeeeeeeeep dive into the garage to find the manual (most were paper in those days, only a readme on the disks). It was a long and very fun night getting all the pieces and parts together and making them run. There was an emulator that runs just fine in linux, a couple that do well under dosbox, played with them all. ahhhhh, back in the day.........
Comments
You can also run CP/M on the Propeller with my Zicog Z80 emulator. Or there is Pullmoll's Z80emulator for the Prop, qz80.
Frank, hold on to those memories. There are sure fun to look back on, and more fun to get hands on.
Home made power supplies and other items can still be built if someone wants to do so. Transformers, rectifiers, capacitors, and other components are readily available.
It would never be like the original. My 5v supply was totally made of parts from Radio Shack, except the cabinet. The LM309K was proudly mounted on the front of the cabinet, with a slide switch and a red incandescent pilot lamp.
My first power supply put out 350 volts (and 6.3 volts for heaters). It used tube rectifiers and a mercury vapor voltage regulator. Built on a home made aluminium chassis. It was a heavy beast.
There is no way I'm doing all that work again!
If we are lucky, we kept all that old equipment boxed up somewhere. The next best thing is a picture. Other than that all we have is memories.
Luckily all I'm forgetting is recent things.
Just a slightly different era I imagine. I did have a tube TV monitor I converted once.
Guess I'm not generally the sentimental type. About the only regret I have is getting rid of the last Z80 system I had. Made a terminal style case that had a complete system in it. Computer, keyboard, monitor, dual floppies, and power supply in an aluminum housing that was as well or better made than any commercial product at the time. Countersunk mounting screws smoothed over with body filler, sanded, and spray painted at an auto paint shop. Went all out on that one.
Before micros, built a 6V DC (1958 VW had 6V system) to 400V 100mA inverter to power the final transmit tube in my 2m (146MHz) ham transceiver. Felt the full blast of this when I got hooked between it while tuning it up
It was just an accident of timing. When I was 12 or so my friend's dad was some kind of contractor that had been installing transmitters for those new fangled color TV channels all around the world. I was also a HAM radio guy. For a year or so we had a bit of an electronics club going on at his house, every Saturday he would teach us some electronics. Volts, amps, ohms, capacitance, inductance, tubes, resonant circuits, radio waves, modulation, detection etc. Eventually a few of us kids ended up building radio receivers from parts in his junk box. A magical time.
Then he and his family disappeared to Australia to install some more transmitters...
Wondering what to do next I discovered the local HAM radio club and signed up there. Those old guys were still mostly using tubes. But one day a guy turned up to give a presentation on the even more new fangled digital logic. With 7400 series chips. That sent me down a different rabbit hole. Resulting in my digital clock with Nixie tubes when I was 15 or so. And eventually to tinkering with micro-processors when we could get our hands on them in 1976.
After all these decades I have finally migrated to FPGA and Verilog. Should have done that years ago.
I like to tinker with tubes from time to time still. Love the glow of those heaters! A mercury vapor rectifier is a beautiful thing. When you are messing with huge U19 rectifier tubes and big capacitors at 1500 volts electronics gets, well, interesting!
http://www.r-type.org/exhib/aai0146.htm
https://www.tindie.com/products/Semachthemonkey/rc2014-mini-single-board-z80-computer-kit/
As seen at the Maker Faire. Had a long chat about them with their creator there. Beautiful looking boards.
With the addition of a few 2K static RAMs that can be made to run CP/M. If you want Altair style blinken lights and switches that's a nice little project to add them.
But it all started with watching a TV repair guy fixing our TV at home, so many times.. so I thank the incorrect voltage (when my father finally figured it out it was just a question of using a different setting on the TV, and that stopped all the home visits by the repairman).
That's great.
I had much the same experience with TVs as a kid. Except the guy I was watching fix the telly was my dad. He was no electronics engineer but he had been building radio recievers as a teenager in the 1930's so of course he was going to crack open the telly and see what he could do.
Now you remind me of a weird thing...
For some reason we did not have a decent TV antenna on the roof when I was 10. Just a piece of wire stuffed into the antenna socket. That was great until an aircraft flew over head. Then the signal would fade in an out producing periodic fizz on the sound and snow on the screen. Very annoying.
A couple of years later I realized what was going on. The aircraft was reflecting the TV signal to us over a non-direct path. As the plane moved that path was changing in length. Sometimes producing an in phase reflection, sometimes an out of phase reflection.
We basically had a radar system in the house!
Where do kids get that kind of experience today?
You had great opportunity to learn electronics, with your dad into building radio receivers.
My father never got out of the tube era, the old Magnavox TV was still in the living room when I sold the house after my parents passing.
What got me interested in electronics was solid state, and then came digital.
You ham guys start the fundamentals of electronic theory using tubes as examples.
The TV shop owner I worked for whas a friend and neighbor to. He would teach me Ohm's law using tubes in a circuit diagram, just wasn't any excitement there. That was probably the best way to learn, but it didn't keep my intention for very long.
I was into radio to as a teen, bought a Realistic Navajo Pro Niner from RS. The fanciest CB base station they had at the time. You still had to have a license, but you didn't have to know anything to get it.
Fun times though putting up a big ground plane antenna on my parents roof. After that was accomplished, I was in charge of the TV antenna also.
But yeah working on them was dangerous and building them was a major project, more metal forming than electronics. Although I did eventually use one of my antique tubes to build an AM radio, from a Boy's Life project published in 1932. Appropriately for something from the Great Depression it required few parts or tools other than its Type 32 receiving tube, built on a breadboard with even the tube socket crafted from bent wires and a homemade variable capacitor and regenerative tuning coil.
Oh. I hope @Heater. does not get in trouble then, being in California and not around Helsinki or such.
So what is a good temperature for Heater.'s life?
Enjoy!
Mike
But around here in San Jose life has been upside down in the past few days. I put my jacket on
because it's so cold in the air conditioned work place. I take my jacket off to go outside for a cigarette.
Still having a lot of fun around here. Even if there is a lot of work to do.
That is an excellent way to develop bronchial problems. Geting sweated up and going into the air conditioning, is a good way to get a summer cold.
Your lungs are huffing on a cigarette in the heat and humidity plus air pollution. And then you make a complete opposite change, and go back into cool dry air.
Drink the sunny California OJ, and get some vitamin C. Don't get one of those summer colds, much more of a miserable experience than the winter version.
Yes. The last thing we want to do is shorten Heater life. There is precious little left as it is.
@MikeDYur,
Funny you should say that. I arrived here with a does of Finnish winter flu. Nearly cancelled the trip. That cleared up pretty quick. A couple of weeks later comes the Californian summer flu. Which does not want to go away after weeks.
It was so hot on Sunday I drank most of a gallon of sunny California OJ. Did terrible things to my stomach. I should stick to beer
Yes, 8 -12oz / day is plenty, acitic acid could be a problem, I think the Calcium content would lead to indigestion.
Nothing brings a headache the next day like OJ combined with grenidene and whatever.
The alcohol and the sugar's just don't mix with the heat either.
Luckily they have Boddington's in Mollymagees in Mountain View.
That sounds more like a meal.
Look for the words Stout and Full Bodied, they are healthy words, and you should feel better for that.
You mean like this:
Edit: Ah, sorry. That won't play here. You have to follow the link.
It played in the states, though you would never see a commercial like that here. Not advertising an alcoholic beverage anyway, margerin maybe.
Don't see beer commercials much at all, just around big sporting events. They are getting a bad rap like cigarettes.