Hi @
Reddinr and @
Cletus
Yes, I realized what you were really saying about 10 seconds after I hit the send button! Isn't it always that way. Anyway, if aging makes electronics more valuable I could sell off some of my 50 year old investments! I think I purchased some of my first transistors in the early 70's and probably still have some of them. Old carbon resistors made back then seem to change value over that time period! I also remember rebuilding my Dynaco 120 Stereo Amp. about that same time. I was still in graduate school. Shortly after that I had a job for a couple of summers where I designed electronics. One project was to built a multi output power supply for a company, Hendrix Electronics, Londonderry NH, who was building and selling text editor machines to the news paper industry. We worked out of some old air force barracks. Later I think they moved to Manchester, NH and got a real building. This is before there were any PCs around, think PDP-8. But we made our own pcbs. I even used tape layout to do the board layouts which were then imaged down at about 20x scale, before they made the boards for me. No auto routers back then.
LSI components were ICs with a couple of flip-flops in it! At that time there was a brand new device that could be had. It was called a 4 bit up counter with carry. No such thing as a down counter yet, so in one project I had to build my own up-down counter from discrete components! We have all come a long way since then.
Yes, my graduate students used ExpressPCB or something like them, but I have not for a long time. To tell you the truth it is nice to have a pcb built, but I prefer to debug circuits where I have lots of room to work and see. The eyes are fading along with other things! Once, they are working then why not a pcb. Surface mount is even harder to work with, but I have the equipment. So I just get down my old supply of discrete components and go at it. In this case once I had everything working I just quit. But a pcb would make things smaller and maybe more reliable.
Before I retired I taught and did research at a major university, EE, Physics, and Materials. There was another process that is available to actually made ICs, called the MOSIS service. It was set up by our military to enable them and everyone else to make small quantities of ICs, before committing to full production runs. You do a full production run and made a mistake it is very expensive. Even small IC masks are multiple $10,000. So doing everything over can be 100Ks just to get the masks made. Several of my colleagues used this service. I only used it once.
https://themosisservice.com/ Anyway, if you need small quantities of ICs, logic or analog, one can sign up. They call the service multi-project wafer design. The service takes lots of folks different designs and merges them on to a single wafer for processing. They use a hand full of commercial IC companies to process the wafers and when they are done they package your ICs and send them back to you. Actually affordable, a few $K, if you really need this. Even less for a student. However, you need some computer tools to do the modelling and the layouts. You send them a Gerber file and they do the rest. If you need speed this is the only way to go. There used to also be a service via them where you can even do MEMS devices. You can imagine it takes a while to get the devices back.
Sorry for wandering off topic. Thanks for looking at my post.
PS. @
Cletus , do you make it to the Caymans? My wife and I have been scuba diving there for about the last 15 years. Really nice. We usually go in the summer when the crowds are smaller. Anyway, they closed down during covid so it has been a while since they would let us in.
