Making tape and sticky symbols on transparent sheets or Edding on copper?
Still have the machine, but, it developed a bad core in the stack around 1982. I’m sure the huge caps on the ferroresonant supply are shot. 250#, 750 watts, .3 MHz with the equivalent of 6 KB of core, just in a 12-bit 4K format.
I used blank sheets that were for the overhead projectors and ordered the tape from Bishop Graphics. Didn’t use a computer for layout until 1997 starting with Protel. Built a “real” light table around 1978 when I was at Purdue. So glad things are easier today. People can put their energy into creation. Of course, in some ways things were easier when just about all logic chips were in a “standard” 14 or 16 pin DIP and everything could be connected up with wire-wrap. Progress means change.
That’s true. Tooling is not that much of an issue nowadays. Just finished a prototype with 2 PCBs and an enclosure. One PCB attached to the bottom half, one PCB (the carrier for Nixie tubes) to the top half.
Tight fit to keep it small. Boards in KiCad - enclosure in Fusion360 - Kicad-Step export to check - 3D print → perfect fit on the first attempt. All free.
I could go on forever, which I will not do 
Nice chat though.
Heckuva nice photo!!
I don’t know what parts your Dpaks are. But my soldering abilities are only fair, and I can hand solder the 3 x 3 mm MOSFETs such as Infineon BSZ series without too much trouble. (The package designations are too confusing and I will not even attempt that.) They pack an amazing amount of power into a package which is much more space efficient than a Dpak. But a Dpak is inexpensive and very easy to work with.
That’s exactly what I’m doing! KiCad, Fusion360 (the software I love to hate), export step file, make chassis, print on Prusa 3D. Also use Fusion 360 to make 3D models when I can’t find something on line.
Had to make/test “rule sets” for different screws and their insets into the chassis, how to get mating ridges that always work, best thickness, etc. This also affects the PCB layout as I don’t use spacers in the chassis, I have the chassis clamp the board down. So I have to leave some 6 to 10 mm diameter room open on the board around the mounting holes. Might be a good topic for a thread someday, “How 3D printed chassis affect your PCB design”… we should share fusion 360 stories and strategies sometime…
BobZ: the DPAKs are mostly because there are a core set of my goto parts. I have the smaller sets, but if space is not critical or I just want a conservative design I use them. On the main PCB for this project, it’s all 0402 and the SC70 (I think) FETs and internally biased transistors.
Basically yes, maybe creating a new category.
It makes me feel all warm and fuzzy inside, seeing current technology used to resurrect a sixty year old icon.
All right, I’ll take the bait:
It would have to be a display for a 10 GHz frequency counter or a clock. 
Far to few tubes for a 10 GHz counter, but enough for a clock. It is a Nixie clock, project name YANC (Yet Another Nixie Clock). IN-16 tubes, ESP32 processor and stuff…
I’m at the stage where I no longer regard the seconds digits as needed for a clock, although my clocks can be synchronised to the top of the minute. 
Sure. Btw, I own a watch with only an hour hand to slow down :-). I just liked the proportions of the 6 digits.
And watching the warm glow as the seconds tick along is mesmerizing.
But then, one IN-16 now is around $10 for NOS, so…
I use NTP for synchronization.
I use my stomach. 
But seriously i have an old Sharp desk calculator with nixies that I rescued from a flea market for a couple of bucks decades ago I should do something with. The nixies from the RTL based iron-constantan thermometer mentioned earlier are already glowing again.
I feel like I should nixie this discussion and send it down the tubes.
OMG…
(Some characters for discourse)
73, 74 in 6 days 
no not really
Back to the ALL IMPORTANT (yeah, right?) topic of the TO220. Yesterday I was looking at my bookshelf and took out a TI Power Databook from about 1973. I looked at datasheets for TIP series power transistors. They do not say anything obvious about their package being different, but I think a sharp eye can pick out the edge of the metal slab running the full length of the package.
BTW I also have an old GE Semiconductor databook. It has datasheet pages describing devices such as D44C5 “color molded” power transistors. Red for NPN and Green for PNP. I could post a scan of either of these but given that they are pages in books, I do not expect the scan results to be great. This GE book is a large paperback which is partially held together with tape…
Ah yes, the colours were cute. I think mine came from a grab bag sold by a company in Texas. At the itme I wished epoxy packages could be more colourful instead of boring black. There was the occasional grey one.
Nixies are just about to have their 74th birthday???
I have some pre-loved Japanese transistors in green. 2SAs & 2SBs… PNPs, scavenged from something or other. I thought they may be of use one day.
Also have some TO220ish (round, goldish colored pins) GE TRIACs in a very pretty light blue. 
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