blast from past

But it doesn't dispense Guinness :-)

I was amazed how many Irish pubs there are in Mountain View. Wish I could have come up and see you but we were on a tightly scheduled round-trip through the west.

--
Regards, Joerg

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Good one :-)

--
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If you go to a Giants game at PacBell Park, you can actually get a hand-made draft Black&Tan for the price of a regular beer. Of course, that's $9.

Drop in anytime.

John

A sheet of kiss-cut peel-off vinyl letters from Flax, the nearby art supply store. They'll eventually rub off, so I'll turn it over to testing and let them pretty it up.

John

If you spray some clear acrylic over it it'll last for years... that's what we did back at university, and there was some really nicely done equipment there that was probably well over a decade old, holding up well. (...although there were plenty of hacked-up boxes with Sharpie marker lettering on them too...)

---Joel

That's what I did as a kid, for my home-made ham radio gear. However, I found it would only hold up to daily abuse if the aluminim was brushed a bit and usually I also heated it before spraying, to the point where the lettering just barely did not begin to shrivel. On non-brushed anodized aluminum it all flaked off in due course. The lettering I used was from a company called "Letra-Set", not sure if available in the US. It was the professional stuff, otherwise used for shopping displays or advertising material.

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Regards, Joerg

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I have used the Letraset solution for about 30 years. It had two point though: It worked very well on sand-blasted aluminium, and was best protected with a proprietary Letraset spray can(alcohol based I think). It survived decades of heavy use without failing. The flaking I only got when using paint from other sources, used with photographic aluminium sheets. Those sheets became ugly very fast, became unstuck at corners.

Being on a student budget that was out of reach for me. I found that 600 grit sand paper did the job nicely. When money was really tight i used

250 grit loaded with chalk. Our teachers threw out the chalk if down to less than an inch and let me have those discards.

Sometimes I used other brands for the letters because Letra-Set could only be bought at "select" stationery stores, meaning lots of money.

Yeah, that paint was always my dream but, back then, also financially out of league. But we have a boat repair shop at a marina, about 45 minutes by bicycle. Their stuff was super tough, and occasionally they'd through a can with remnants into my always wide open duffel bag.

What I did a lot was brush the aluminum, paint it under a lot of heat, then Letra-Set and then clear-coat. That way not all my stuff had this dull-silvery look. The color selection was not by taste but by whatever was on sale, poison-oak green and so on :-)

Like this amplifier:

The scratches are from transporting and heavy use, otherwise quite a tought front panel.

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Regards, Joerg

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I built a controller for a scanning tunnelling microscope (someone else had designed the circuitry and had boards made -- I just had to stuff/solder the boards and do all the mechanical work -- and let me tell you, it had a LOT of pots and switches on the front panel...) once and used a sky blue front panel (this was 3U rack-mounted) with ~1/8" thick horizontal red pinstripes at the top and the bottom and black lettering.

I thought it looked pretty cool.

A few other people referred to it as the "Fisher Price" controller. :-)

Ah well... for the kind of peanuts we were being paid as student hourlies, no one was seriously complaining.

Normally for rack-mounted gear we used front panels from Bud, which came pre-painted in beige (the shop kept them in stock). Although I once bought a few rack chasses for work projects from some company that focused primarily on audio electronics that were semi-gloss black, which looked pretty sleek.

Didn't anyone tell you anything green has to be environmentally "sensitive?" How does a linear amplifier fall into that category!? :-)

Seriously, it looks good. Nice job...

---Joel

I'd probably have done it all in red, white and blue :-)

I also like black but that required white Letra-Set labels. Those were special order and super-expensive.

This amp was decidedly non-green. The filaments alone guzzle 200W. Legal limit was 750W and that could easily be done with the usual 230V/16 circuit. But if you drove it hard one brief whistle into the mike ... poof ... all lights out.

Thanks. Inside it's a bit more rag-tag though. Had to use what was there. For example, the plate terminal coolers you can see in the back aren't the prescribed stock. Those would have cost tens of bucks. So I sawed off some pieces of heatsink. Looked pretty cool, too. But woe to anyone who thinks they look innocent and touches one, 5kV on there, from a power supply of the same 19" size as this amp.

--
Regards, Joerg

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No wonder you begrudge every penny spent on parts. Reminds me of the Woody Allen bit: "We were so poor, we couldn't afford a dog. So I had a pet ant. We called him Spot."

John

It's pretty hard to design this stuff out when physics keeps getting in the way. ;-)

The I/O is 150ohm audio floating on a substantial DC offset (too close already, in fact). It is what it is. There are a few places I can switch parts, but that'll cost another feeder slot, which I'm not sure we have (the part numbers were originally consolidated to save feeders). There are other places where it's a lot easier (as you note, 10uF 10V is a simple substitution

- almost).

Never had trouble with anodizing flaking off. Maybe you got E. German aluminum. ;-) I think I still have my transmitter and last time I checked (when we moved - '08) the panel was still in good shape. I used Letra-Set on that, too, with DataKote (?) sprayed over it. I built the transmitter in '66.

Actually, no. I spent quite some money on vacuum-variable capacitors, tubes, sockets, made my antennas only from the good stuff (aircraft grade aluminum), and so on. But I skimped on cosmetic stuff such as front panels. And under no circumstances would I dip into the brewsky budget, ever.

The penny-pinching came later, on the job, when I had to do my first mass-produced designs,

Cool :-)

--
Regards, Joerg

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It wasn't the anodizing that flaked off but the spray coating lifting from the anodized surface. Worst case where a letter or number was.

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Audio, did you say audio? The laws of physics don't apply to audio! Just bring more money ....

Sorry, I couldn't resist. :-)

Ed

have

Not stuff for the living room. *FAR* more expensive stuff than that. ...and not nearly as pretty. ;-)

;-)

Never had that problem with DataKote, unless it was damaged (scratched).

How does one determine the brewsky budget? Is it a fixed amount per week, a certain percentage of income...?

Could the brewsky budget be raided for, e.g., dinner dates with attractive women? :-) (I recall a couple of times I was raided funds fully intended for something else because some girl said, 'yes...')

Just curious... :-)