You need some friends that will arrange for you to blindly sample your before and after circuit.
No, I didn't start college until I had already become an engineer (age 37). That way my company paid for my two degrees.....much cheaper than student loans!
I had modern technology, 5 1/4 inch floppy disks.
Time frame......well lets just say that my newly DIY super computer had an Intel 80386 chip overclocked to 40 MHz and ran two 80 Megabyte Seagate 4096 hard drives.
My computerized projects used Motorola MC68HC11's.....It would be 4 or 5 more years before I discovered the PIC16C54......but once I did, one of my little projects used 1/4 MILLION of them!
I went to a technical high school where I took a 3 year vocational electronics program. 1967 - 1970. The textbooks were early 60's vintage with a mix of tubes and some transistors. No mention of IC chips. The labs were 100% vacuum tubes since much of the material came from Homestead Air Force base. They had shut down their training facility.
Power tubes.......do you know how many NOS (metal) RCA 6L6's I blew up in high school......I don't remember because there were hundreds of them in the stock room to play with. I won a bet with the teacher that I could make the outer metal casing glow red. Stunk up the entire vocational building. We had DIY tube guitar amps routinely cranking out well over 100 watts, only limited by the OPT's we could scrounge.
I ventured into the SS world too, here is a picture of a power amp I made in high school. 6 X military surplus power transistors, one 75 volt 4.5 amp transformer, for about 100 volts of B+ gave the neighbors a real headache, and maybe 250 watts RMS at a whole bunch of THD (we had no way to measure it). I found this thing and several other of my early projects in my shed when I was preparing to move. I plugged it in to see some smoke and a blown fuse. I put in a fat fuse and watched from afar to see if it would blow up, but nothing. The transformer killed the wimpy little diodes.
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The transistors got HOT, so I stuck in the first thing I could find at the scrap yard. It blows air downward into the chassis which comes up through slots under each heat sink. I built this thing in 1969 or early 70. My DIY skills were pretty poor back then, note the 1 X 2 wood support for the heat sink, and the excellent quality cutting job on the chassis, all done with a nibbling tool. This is just the output stage. It used the transformer driven "totem pole" design common in solid state stereos in the mid 60's.
I almost forgot, the flip side of hate.......The project that nearly met it's demise just a few days ago is now working good, and making sweet sounds. Some of the code that I had butchered up in an attempt to find my "mistake" is now working. There are a few more chunks to write, then it will be time to populate the right side of the breadboards.
I have already figured out several ways to make it better. I hate that stuff too, like why couldn't I have thought of this BEFORE I wired all of this up? Now, do I rip some wiring up, change a few parts (like those ugly white connectors) and do it over, or wait for the next version.........I'll make that decision after I have a few more successes with this version.
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Smoke 'em if you got 'em !
Verification that the dipped mica caps, which seemed way too small to be rated at 500 DCV as marked, after the electronic supermarket's owner assured me that they ARE 500 volt rated, were not in deed not.
That is, when the Dyna Stereo 70 that I just finished refurbished with all new components... Catches on fire ( I'm talking about B+ arc flash), and the acrid vaporization of phenolic. Toast, burnt, end of story, end of PC board.
The sound through my JBL monitors, 4310's, was extreme and downright frightening.
Well at least the owner's reaction to me telling what was up with his mini 500 V caps, when I told him what had happened, I was able to predict through my psychic abilities. Shrugging of the shoulders.
Funny, when I first looked at those little buggers I had a feeling...
-DAAB-
Verification that the dipped mica caps, which seemed way too small to be rated at 500 DCV as marked, after the electronic supermarket's owner assured me that they ARE 500 volt rated, were not in deed not.
That is, when the Dyna Stereo 70 that I just finished refurbished with all new components... Catches on fire ( I'm talking about B+ arc flash), and the acrid vaporization of phenolic. Toast, burnt, end of story, end of PC board.
The sound through my JBL monitors, 4310's, was extreme and downright frightening.
Well at least the owner's reaction to me telling what was up with his mini 500 V caps, when I told him what had happened, I was able to predict through my psychic abilities. Shrugging of the shoulders.
Funny, when I first looked at those little buggers I had a feeling...
-DAAB-
I was given the nickname "ZAPPA" in high school. It had nothing to do with Frank, and a lot to do with the sound that often happened whenever I was around.
There was this 6 foot tall Tesla coil that I built for the science fair modeled after the Big TC in Popular Electronics magazine, but upsized by me.....and after plugging it in a few times, banned from the science fair. Then there was the aluminum foil and power lines experiment......
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I ordered a PC board for a music synthesizer module from about 200 miles away last Saturday. I ordered the parts to populate it from Mouser at the same time. They are 2000 miles away. The Mouser parts were here yesterday. Maybe the postman brings the PCB today?????? The parts are all laid out on the bench......waiting for their new home.........
This so much. Either waiting on PCBs to get back from the fab or waiting on that one jigget you need to make the whole thing work, or something else. It's always something.
I've been waiting on my 4P1L transformers for a month now and I have another month before my biasing circuit PCBs get shipped to me.
Hunting for reasonable priced SE OPTs.
Only having one of a fantastic amplifier tube, and wanting to build a stereo amp. Then finally finding another at an astronomical price.
Being short one cap, and having to order several, just to get free shipping.
Finding that the filter cap specified is made of unobtaineum and have already gone too far to quit now.
Just when I need it most, my VTVM dies, and needs overhaul.
Finding that some of the component values in the schematic are wrong, and need to modify it, just to get it to work. Then modify it further to get it to work well.
Only having one of a fantastic amplifier tube, and wanting to build a stereo amp. Then finally finding another at an astronomical price.
Being short one cap, and having to order several, just to get free shipping.
Finding that the filter cap specified is made of unobtaineum and have already gone too far to quit now.
Just when I need it most, my VTVM dies, and needs overhaul.
Finding that some of the component values in the schematic are wrong, and need to modify it, just to get it to work. Then modify it further to get it to work well.
As a speaker builder gluing then clamping then having to wait hours for the glue to harden.
