Hello All

@joelindo

Hi Joe
Digital electronics has come a long way since the days of relay or tube based flip flops 🙂
Now we can carry a highly advanced solid state based computer in our top shirt pocket with all sorts of advanced functionality.
So what is your particular interest in electronics these days?

@joelindo Hi Joe, so you worked on one of the big disk drives, I remember when they were 5.4 MB. Also an old tube guy, but such things as flip flops wasn't invented yet when I was in school. Welcome aboard.

@robotbuilder Well, I've made a few projects, all using RasPi and Python3. I built a clock with 2-inch tall 7-segment displays. Since the each of four displays require 8-bits of parallel data, the challenge was getting the Pi to do parallel data. I don't compute the time, I download it from the internet. . . I built a garage/mailbox door monitor that texts my phone every time either door opens. I can also control the garage door through the internet when away from home. . . I also made a PM2.5 monitor using a PMS7003. It has audio that announces the current quality of the air in the house. I recorded the g'daughter's voices, which my wife Lucille loves: "Grama L, the air quality is green, yea!!" It also texts our phones when the air quality changes, and it can turn on a fan through the LAN. (I'm having trouble with Python Sockets. The server running on the PM2.5 sensor just stops running after a day or so. No clue why.) The PM2.5 sensor program and the server program run independently from each other on the Pi. The PM2.5 program writes the current status to a text file on the Pi and the server program reads that file and sends the current status to the client which controls the power to the fan. . . I also built an ozone component "sniffer" using the Sensirion SVM41 development board. The output is a monitor displaying the level of volatile organic compounds (VOC) and Nitrogen Oxides (NOx), as well as temperature and humidity. Gasoline is an example of a VOC. When burnt in a combustion engine, one of the outputs is NOx. VOC plus NOx puls heat and sunshine can produce ground level ozone.

I tried a project using RFM69 radio modules. I bought two modules and tried to make them talk to each other using Python3. I was able to read and write to any register in the transmitter and receiver, however I could never pass data through the antennas. Maybe I don't know how to program the radio. There are too many variables. Is the transmitter bad? Is the receiver bad? Are the transmitter registers setup correctly? Are the receiver registers setup correctly? Did I make a mistake when creating the circuit board (KiCad)? I may have to buy a pair of tested and working modules and try to decipher the C-program that comes with it. I don't have a reason to send data through antennas. I just want to understand how it works.

@zander The disk drives were much smaller in the late 60s. The 300-MB ones came in the 80s, I think. I don't miss those days. Remember the big floppy disks? 8-inches, I think. I once worked for Digital Equipment Corp. (DEC) They were number two to IBM before they died a horrible death. The company presumed, incorrectly, that distributed processing was going to dominate the future, and they invested heavily in that direction. They also gouged their customers. The OS was unique and proprietary. If a customer needed floppy disks, they had to purchase them from DEC at very high prices. They couldn't purchase blank floppys and format them on their own. I worked on the PDP11 series, PDP8 and the VAX series. There was a PDP1 at the University of Hawaii, Manoa that I saw. They wouldn't let me touch it, however.

So tell me about your electronic history. Doesn't sound as if you were into computers then.

@joelindo My very first computer was a gift to my high school electronics class, it was a Ferranti-Packard Canada analogue machine. It was more a teaching tool than any kind of computer you would recognize today. During the summer I worked at Westinghouse switchgear and the pipeline computer was very similar to a Konrad Zuse early machine. I studied electronics, but never really worked at it, one of my first jobs was as a steel company industrial electrician but they were slowly converting to electronic controls. Then I went to work at IBM Canada 1966 and was 1401 trained, then 360/65 then software support then HQ IS rising to staff analyst. I then 'defected' to a competitor, National Advanced Systems. They had the fastest computer at the time and it was called NAS 9000 (remember HAL 9000, HAL was IBM -1)

Did some contracting before going to what would become after a series of takeovers Dow Jones where I became head programmer. When they went bankrupt I started my own company but on Sep 11, 2001 I was effectively put out of business. I have been mostly retired since then. Now I am returning to my roots playing with Arduino, Raspberry Pi, and ESP's.

@joelindo

Hi Joe and a warm welcome to you.

Impressive pen picture of your early career and I suppose you know the origin of the term 'bug' and what a tap test is?

@zander - I remember using and programming 2 Mbyte fixed head Borroughs disc drives, also the size of a large chest of draws! For the time they had an impressive access time - 17.5 milliseconds.

The thing about nostalgia is that it can be addictive, ah, halcyon times.

Anyway, enjoy the forum, Joe, lots to explore.

Regards

Ron B

@ronbentley1 I know where 'bug' came from, an insect got between the contacts of a relay thus a bug caused the logic failure.

Now tap test I am not sure, but maybe referring to literally using the non-conducting end of a screwdriver or similar to tap the relay in case the contacts were not quite making contact.

@zander 

Ron,

Yes, bang on.

A little tap was used in a weekly check of circuits and components to weed out the weak

Ron B

PS

I still use the tap test today, but now on everything I dont find working properly! Ha, ha.

😊

@zander The IBM PC changed everything, didn't it? They made it "open architecture." IBM assumed, having ROM at the top of memory would be a permanent block to expansion, thereby limiting the PC to "toy" status. Lots of very smart people out there proved IBM wrong, which ended up good for all of us. It was amazing, the similarities between the DEC computer architecture (any model) and the Intel 8086, 286, etc. Virtually the same, except it was all shrunk down to the size of my littlest finger nail. In the old days, we had to be very familiar with the architecture because we had to troubleshoot the discrete components that made up the system. Today, I have no idea about the architecture. It runs for years, instead of days, and when it goes bad, I upgrade at very little cost. Amazing!

@joelindo It was hilarious watching IBM going from open to closed and back to open, and then Apple who had all proprietary hardware and software eventually were running BSD Unix on a PC. When I finally switched to Apple after about 37 years of IBM and clones I found Apple hard to understand and navigate. I think the so called user friendly aspect is different for techies and artistic types that were 80% Apple users. Now IBM has a Unix subsystem and I know some of the team who helped Microsoft finally produce a decent OS starting with Windows 2000. It was much more of a rewrite than most knew. That team and I were 'fault tolerant' types, I had to write software that never failed and the hardware also had to be reliable, they used 4 physical CPU's for each logical in a pair and spare configuration. That business is almost over if not already as hardware is much more reliable and the software the current job holders write is just a tiny layer on top of the foundation old 'close to the iron' guys like me laid down for them. The good old days? I once spent 32 hours straight looking at scope traces of the boot up clock cycles until a guy from the plant came to help and remembered seeing the same problem once before. The fix was to run a wire from the SMS J (ground) pin to under the head of a screw in the frame! Now THAT was a bug!

@ronbentley1

The thing about nostalgia is that it can be addictive, ah, halcyon times

And even when we live in the same physical space we all occupy our own personal unique emotional space to be nostalgic about. As I have only ever had a hobby level interest in electronics and programming while earning my living in a completely unrelated area I have had a much different experience to be nostalgic about and think of as my halcyon days compared with yourself, @joelindo and @zander.

Posted by: @ronbentley1

The thing about nostalgia is that it can be addictive, ah, halcyon times.

Nostalgia's not what it used to be 🙂