EEVblog #545 - Vintage Design Rant

[M0BSW]

At work we have the  Golden turd award, given out to people usually management when they messed up somehow, perhaps you could do similar as it's your blog site/forum, for anyone who makes such mistakes, you may like to consider calling it the GOLDEN TURD AWARD  or PILLOCK OF THE WEEK AWARD, or WHOOPS I  WISHED ID KEPT MY MOUTH SHUT AWARD, I commend this idea to the  members
ps encase you were wondering, the golden turd is a plastic replica plastic turd bought from a joke/ prank shop, sprayed golden and mounted on a piece of ply wood, and presented to the latest victim,on a Friday lunch time in the canteen where full applause and jeering takes place.

a golden-foot-in-mouth award.

Yes that's a good one

[Whuffo]

In the "olden" days, amazing things were done with small component counts. TV sets with 16 vacuum tubes, radios with 5 of them. And they worked well - given the technology of the time. This kind of elegant (usually) design continued on into the 80's with germanium, then silicon transistors - but now our younger engineers look at a project and throw a million transistor IC at it and call it good. Is this better? Sometimes it is, and sometimes it just shows extremely lazy engineering.

Dave looks at test equipment and some other higher end equipment - but the electronic items that sell by the million are inexpensive - in part due to the elegant design of the circuitry where not one transistor or PC board trace was wasted. Billions of talking greeting cards have been sold - and a Arduino solution here would work, but it's overkill and far too expensive for the market. Furby sold by the millions - and there's teardown videos all over YouTube. No fancy MCU in there, either - and the mechanical design is a work of art.

I'm not trying to disparage Amtel or PIC micros; I use them where they're appropriate. But real engineering isn't all about getting the design done in the shortest amount of time (to heck with the cost) - it's about making the product happen using the least complicated (and least expensive) circuitry. And you can get many valuable clues about how to do it with the minimum by looking at what engineers of the past have done.

Those who think that the younger generation are superior to us graybeards are fools; you might very well be superior one day, but until then you'd do well to listen to the advice of those who have done the job since before you were born. You could learn from our mistakes and our successes and get to be superior even sooner.

[Dave]

Those who think that the younger generation are superior to us graybeards are fools; you might very well be superior one day, but until then you'd do well to listen to the advice of those who have done the job since before you were born.

I'm sorry, but this is the kind of dickhead attitude that annoys the sh*t out of me. I am sure you know many things that a young whipper snapper may not, but that doesn't give you the exclusive right to lecture every young engineer and treat him like a moron. I have worked in a team of EE's during the summer and there were mostly guys around their thirties and one guy who was over 60. He spoke down to us and acted like he was the only one who knew what he was doing there.

Well, I was working on some circuit, and because the guy I was usually working with was on vacation, I asked the graybeard for some advice. He explained some things to me, and sketched a quick and dirty schematic. When I thought he made a small mistake, I asked him about it and got yelled at. I then left his desk with my tail between my legs and continued working. About half an hour later he figured out that he did in fact make a mistake and that I was right. No apology whatsoever.
You know what that resulted in? I never asked him about anything ever again. Even if I was not exactly sure what to do, I just did what I thought was best, and rather corrected the mistake later than listen to him. Is this how a team should work?

When I whined about it to the other guys at lunch break, they just told me: "Get used to it, he's always right. But don't worry about it, he's retiring in 2 years anyway." A fine example of a well-functioning team, don't you think?

[Alexei.Polkhanov]

There is nothing wrong with retro teardown. Even if equipment is 30 years old it may not be completely obsolete and it is easier to teach principles of design on older equipment. When I look at something like that it always make me wonder - where is technology now? What do they use in modern equipment.

I have seen some photos of similar equipment where board was populated with surface mount resistors that are laser trimmed and coated with something after they are installed. Next question would be which resistors are used for that?  These http://www.vishay.com/docs/61011/sc7scb.pdf ? I don't think it is very modern solution either, but applicable YAG lasers are much more affordable  now.

These 0603 ones have dR/R 0.1%: http://www.vishay.com/docs/28893/usinglasertrimmableresistors.pdf. There have to be models that allow higher accuracy.

[walshms]

I asked him about it and got yelled at. I then left his desk with my tail between my legs and continued working. About half an hour later he figured out that he did in fact make a mistake and that I was right. No apology whatsoever.
You know what that resulted in? I never asked him about anything ever again. Even if I was not exactly sure what to do, I just did what I thought was best, and rather corrected the mistake later than listen to him. Is this how a team should work?

When I whined about it to the other guys at lunch break, they just told me: "Get used to it, he's always right. But don't worry about it, he's retiring in 2 years anyway." A fine example of a well-functioning team, don't you think?

The exception or the rule?  Sounds like this particular "greybeard" just has an attitude.  In my experience, most don't.

[sync]

These 0603 ones have dR/R 0.1%: http://www.vishay.com/docs/28893/usinglasertrimmableresistors.pdf. There have to be models that allow higher accuracy.

TC of 50-250ppm/K

[Dave]

The exception or the rule?  Sounds like this particular "greybeard" just has an attitude.  In my experience, most don't.

I am not saying all graybeards are like that. I know many that are happy to share their knowledge and experience, and are happy to listen when you teach them something new.
That's how it should work. But when you have a graybeard that feels threatened by the whipper snappers, everything falls apart.

I had to say it, because Whuffo sounded just like one of those cranky old bastards: "I'll do the talking, and you do the listening, kid. You are young and don't know squat."

[lilshawn]

geeez... this sounds like the kind of guy who would:

1) go ahead and build his own resistance tester with modern surface mounted components

2) find out that for some reason the LOW ohm scale reading error are WAY out to lunch (because of actual trace resistance skewing things...but he wouldn't know that)

3) find out that for some reason the HIGH ohm scale reading error are WAY out to lunch (because the board itself actually conducts a tiny amount...but he wouldn't know that either)

4) put said error specifications on the product anyways and/or market it as a feature

SHAKE MY HEAD.  (also bang)

[trackman44]

I love the fact that it has a Z80 chip inside. I learnt to program in BASIC on a Z80 based computer (ZX81). Then I acquired the ZX Spectrum and learned to program in machine language! Ahh.... brings back good memories Love the teardown by the way. You learn allot, it's all there for everyone to see what's going on. Nowdays every thing is system on chip or FPGA. Nothing to see here folks!

Will

[vk6zgo]

what would people want. . Let's teardown a kindle..
Here is an e-paper display which was custom made , specs ink own, pinout unknown , how to drive it unknown , and you can't get it anyway.
Here we have the circuit board. It conatains a system-on-chip , custom made, specs unknown. Here are a few resistors and caps, and there isa flash chip and there the radio, also custom made specs unobtainium. It uses a 4 layer circuit board made in china.
Look the case is flimsy plastic held together with clips.

End of teardown.
What have we learnt ? Nothing.



Most likely the same complainer messes around with hardwhinos and prebuilt shields. Has no clue how to wire up an opamp let alone what rail to rail is.... His schematics are spaghetti consting of loose parts scattered aroind with netnames on every pin. The two wires that are drawn cross the chip symbol and his pcb' are all laid out with the same trace width and holes that are either way too small or way too large. Heatsinks are in the middle of the board , connectors are mounted updside down and the end result looks like something the cat threw up, the dog peed on and was then mounted using hot glue in an old tupperware box which was subsequently nailed to the wall.
It does have a blue led (albeit with the wrong value series resistor so it will die prematurely.

 

Now,that's a rant!!

[AlfBaz]

<snip> pcb' are all laid out with the same trace width and holes that are either way too small or way too large. Heatsinks are in the middle of the board , connectors are mounted updside down and the end result looks like something the cat threw up, the dog peed on and was then mounted using hot glue in an old tupperware box which was subsequently nailed to the wall.
It does have a blue led (albeit with the wrong value series resistor so it will die prematurely.

How'd you get your hands on my design rules??

[Circlotron]

In the "olden" days, amazing things were done with small component counts. TV sets with 16 vacuum tubes, radios with 5 of them. And they worked well - given the technology of the time.

My idea of good engineering is to accomplish the most you can, given what you have. Vintage radios using regeneration, also reflex circuitry that amplifies rf, turns it to audio then passes audio through the same stage for a second pass at amplification. And look at the effort that went into getting horn loaded and bass reflex speakers right instead of just chucking a gigawatt at black hole of a speaker. Another example is the SU carburettor - unbelievably simple yet gave results WAY out of proportion to it's simplicity. -> http://www.mossmotoring.com/wp-content/uploads/2012/06/SU-Carb-Weber-Carb.jpg

I reckon a teardown of an old tube/valve B&W TV set would be the go. That's where I learnt my stuff in the early 70's.

[czdt8m]

At work we have the  Golden turd award, given out to people usually management when they messed up somehow, perhaps you could do similar as it's your blog site/forum, for anyone who makes such mistakes, you may like to consider calling it the GOLDEN TURD AWARD  or PILLOCK OF THE WEEK AWARD, or WHOOPS I  WISHED ID KEPT MY MOUTH SHUT AWARD, I commend this idea to the  members
ps encase you were wondering, the golden turd is a plastic replica plastic turd bought from a joke/ prank shop, sprayed golden and mounted on a piece of ply wood, and presented to the latest victim,on a Friday lunch time in the canteen where full applause and jeering takes place.

I used to work at a company that had a yearly "Red Face Award" for the worst performing supplier. (this was a car manufacturing company)
Glad it wasn't us as we did the IT support for them. 

[poorchava]

I find it most educative to tear down discrete semiconductor electronics (like 70's audio amps for example).

It's quite often these times that people don't know how to build a simple voltage amplifier out of transistors. They use an opamp ic - easy and cheap. But what if you need to work at 50V levels? They take a more expensive opamp. Ok. What about 150V? Foooook. Even if there's one that can do it, it will cost you $30 a piece or something. You can make it out of discrete transistors for $2 tops.

[Oracle]

Vintage teardowns are a gold mine of information, and vintage stuff is simpler than recent one (at least for me) it's more understandable...   

[Synergy Hub]

 Dave,
Glad you did a rant video reply to that way off base comment.   I have taught Project Design for over 40 years and the first thing I do is work on getting rid of the attitude many new "engineers" have that there is no point in looking at older designs.   They are the same ones that will take months to design something "great and new"... and have wasted their time and the companies money because it was actually designed better long ago.   

Any person in Any field that does not know the History and Prior work that has been key to the ongoing development is frankly a fool.  Case in point... had one spending a huge amount of time and money to "develop" a way to reset a system each day...  he was using RTC chip, microprocessor, power driver module....   I said just put a 555 on the board set to 24hrs.   He said, and I quote "what is that?".

Other comments here have referenced "greybeards"...  If it was not for us... you would be still cooking on an open fire.   Progress is based on a foundation of people and work.   Pity in some circles the elder pioneers are not respected.

[vk6zgo]

I find it most educative to tear down discrete semiconductor electronics (like 70's audio amps for example).

It's quite often these times that people don't know how to build a simple voltage amplifier out of transistors. They use an opamp ic - easy and cheap. But what if you need to work at 50V levels? They take a more expensive opamp. Ok. What about 150V? Foooook. Even if there's one that can do it, it will cost you $30 a piece or something. You can make it out of discrete transistors for $2 tops.

Yeah,people fall in love with a particular way of doing things!
We had a guy on another forum who tried to make a VLF radio out of Op Amps,with an untuned voltage follower input stage,followed by the sole tuned circuit in the input of a gain stage,then another untuned voltage follower.

The thing oscillated!

Even after he "fixed" the oscillation,it was so insensitive that it didn't receive a thing!

He wanted to know why ordinary Op Amps weren't used n the RF sections of receivers.
I pointed out that the early ones  were unusable,(poor bandwidth,instability,etc),& by the time that they were a bit better,any applications in radios had been taken up by better purpose designed devices.
.

[vk6zgo]

Dave,
Glad you did a rant video reply to that way off base comment.   I have taught Project Design for over 40 years and the first thing I do is work on getting rid of the attitude many new "engineers" have that there is no point in looking at older designs.   They are the same ones that will take months to design something "great and new"... and have wasted their time and the companies money because it was actually designed better long ago.   

Any person in Any field that does not know the History and Prior work that has been key to the ongoing development is frankly a fool.  Case in point... had one spending a huge amount of time and money to "develop" a way to reset a system each day...  he was using RTC chip, microprocessor, power driver module....   I said just put a 555 on the board set to 24hrs.   He said, and I quote "what is that?".

Other comments here have referenced "greybeards"...  If it was not for us... you would be still cooking on an open fire.   Progress is based on a foundation of people and work.   Pity in some circles the elder pioneers are not respected.

A friend of mine told me about the time that his Employer was trying to make a event counter which would count the total number of operations on a production line.
It didn't have to interface to a computer or anything,just give a readout.

My mate bought a cheap calculator,butchered it so it would always  perform the + 1 function,connected it to a microswitch which tripped each time the operation occurred,mounted it where it was needed,and all was well!

[Circlotron]

A friend of mine told me about the time that his Employer was trying to make a event counter which would count the total number of operations on a production line. It didn't have to interface to a computer or anything,just give a readout.
My mate bought a cheap calculator,butchered it so it would always  perform the + 1 function,connected it to a microswitch which tripped each time the operation occurred,mounted it where it was needed,and all was well!

You can do really neat things with a simple calculator and an approach like that. For example put a magnet on a bicycle wheel and have a hall effect sensor or reed switch pulse whenever the wheel completes a rotation. Feed it to the = button on the calc. Measure the circumference of the wheel, say 2.573 metres, = 0.002573km. set up the calc by keying in 0+0.2573. Every time the wheel rotates the calc increments by 0.002573km. Bob's your uncle! Instant digital odometer in km, or whatever units you desire.

[TheWelly888]

I watched your rant before I watched the teardown video!

Thank God (or whatever) for this forum, I can comment on your videos without effing around with G+!

[ResR]

That Google+ $&/t gives me a headache too. They try to force on a product that failed to achieve it's purpose to compete with facebook.
I agree with Dave too. Also vintage electronics parts are much more easier to reuse. Try to desolder and sort by value SMD 0402 parts, or hand solder them onto new PCB. Or desolder and reuse BGA or QFP chips (not to mention if it has any use at all).
 
Not an easy task, specially for beginners.
I have saved only few LED's size 0402 "collecting dust" in my SMD LED 10mL test tube.

[josko]

I am for vintage equipment teardown as well, it was thing that made me come over to eevblog.
I love old stuff, I would suggest to get even more vintage equipment especially test equipment..
Some old tube oscilloscopes.. ones designed for 100MHz with tubes!! That was true black art where all the tube components acts as antennas and designer had to take that into account.
Or what about this beast? that's just thing of beauty - 2kV transformer in oil, mercury arc rectifiers.
And tearing down Kindle, iPads, laptops or toy walkie-talkies? Give me a break... You can tear down those at home.. they are everywhere.

[CJWarlock]

Dunno if it's a right topic to say it but I'd like to see a Commodore 64 teardown - Dave's style.

[Alexei.Polkhanov]

Dialog in a museum:
- What do you think Leonardo Da Vinci would have painted if he was alive today? With all these new pigments that were not available back then...
- Do you think Leonardo was advanced men for his time?
- Yes, very advanced!
- Then he would have used best SLR camera and MRI machine he could find.

[c4757p]

More like "why study the methods Da Vinci used when I can use clipart?"