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General => General Chat => Topic started by: XOIIO on July 28, 2014, 05:05:05 am

Title: Share a time you realized something you are workng with is obscure.
Post by: XOIIO on July 28, 2014, 05:05:05 am
Just had an interesting moment, looking for some software to read the files from my nettest cma 4000, so I searched for "nettest cma 4000 software", not much luck, I probably have the link saved somewhere, but this sort of equipment is so obscure that my video doing the teardown is on the first page of google.

I guess I've made it big time!  ::)

Anyways, have there been any times you realized something you are dealing with is very obscure or something you posted is one of the main results?
Title: Re: Share a time you realized something you are workng with is obscure.
Post by: EEVblog on July 28, 2014, 05:14:17 am
I once tested the shock and vibration response of feminine hygiene products for an engineering application. Putting in the receipt for maxi-pads to accounts raised few eyebrows.
Title: Re: Share a time you realized something you are workng with is obscure.
Post by: TheBorg on July 28, 2014, 05:58:16 am
Teardown of a Hakko FR-802 rework station - not a whole lot of documentation there. My teardown page on EEV made the google front page.

Most recently tearing apart a TAMRON 18mm-250mm Canon-mount lens to fix a broken FPC. The best teardown information I could get was a rough render of a cross-section of the lens...

Daves is pretty good though!  :-DD
Title: Re: Share a time you realized something you are workng with is obscure.
Post by: edpalmer42 on July 28, 2014, 06:12:38 am
I'm starting a project to use an FPGA to replace a dead, obsolete chip in a Cesium Frequency Standard.  Talk about a niche market!  :)

Ed
Title: Re: Share a time you realized something you are workng with is obscure.
Post by: EEVblog on July 28, 2014, 06:19:56 am
I'm starting a project to use an FPGA to replace a dead, obsolete chip in a Cesium Frequency Standard.  Talk about a niche market!  :)

That #1 spot on google adwords will be worth a fortune!
Title: Re: Share a time you realized something you are workng with is obscure.
Post by: calexanian on July 28, 2014, 06:22:06 am
Oh, where to start. I designed and manufactured a cycle timers for dispensing glyphosate in a very environmentally friendly manner. Proud of that one. Modified one of our filter backflush timer systems to be used in breweries to clean out beg kegs. Well our filter backflush timers for that matter. Only used in automated filters for irrigation. Thats pretty obscure. Helping my friends company build and re engineer the 6303 vacuum Rectifier still used to this day in ground launched missiles around the world.  I had to design a new filament. Thoria bonded tungsten that was. Pretty obscure there. Used to wind replacement power transformers for Hammond organ consoles.  too many other one offs and customer "Please make us something to fix this problem" type things over the years.
Title: Re: Share a time you realized something you are workng with is obscure.
Post by: calexanian on July 28, 2014, 06:24:33 am
I'm starting a project to use an FPGA to replace a dead, obsolete chip in a Cesium Frequency Standard.  Talk about a niche market!  :)

That #1 spot on google adwords will be worth a fortune!

Ok, everybody go think of good phrases and meta tags to put in. Sagan will be of collage age in a blink of the eye and Dave needs a huge stack of money to pay for it!
Title: Re: Share a time you realized something you are workng with is obscure.
Post by: T3sl4co1l on July 28, 2014, 07:10:55 am
Induction heating.  Started playing with it years and years ago; a bit more recently, I realized there's only maybe three or four people on the internet that are actually doing something on the same scale (upwards of 5kW, suitable for melting and forging metal) and sophistication (i.e., basic things like frequency control and current limiting, let alone UL-required safety features, and common features like timers or profile control).  Worldwide industry is in the low $B/year, which sounds like a lot, but maybe three or five companies account for well over 90% of that.

Like power transmission, it's actually a very slow, lumbering business.  Tube oscillators from the '80s are still in wide service, and resale from time to time.  Yes, '80s -- again, tech moves slowly -- while motor controllers ranging from gen sets to SCR or BJT-fired VFDs have been around since the '60s, those technologies have been only slowly accepted in this field, and at that, mostly for low frequency, high power purposes -- at least, when the hockey puck style devices were utilized.  Which again, is around about the time solid state HVDC inverters hit the marketplace.

Tim
Title: Re: Share a time you realized something you are workng with is obscure.
Post by: Lightages on July 28, 2014, 07:32:14 am
I designed and commissioned a vacuum chamber and system that had a manipulation stage that held a pure beryllium mirror and cooled it down to liquid helium temperatures. I was basically a far infrared mirror characterizing goniometer that was going to be used to test the targeting systems for the US Star Wars defense initiative. The story I was given for the use of the system at the time was to test laser systems that were going to be used for de-icing the space shuttle windows in space. Then when the information was declassified I was told the real truth, although I knew the original story was a smoke screen.
Title: Re: Share a time you realized something you are workng with is obscure.
Post by: bwat on July 28, 2014, 07:58:07 am
or something you posted is one of the main results?
I'm on the first page if you google "Hintikka's lemma", the second page if you don't give the apostrophe. Why such a high ranking? I don't know something is not quite right.
Title: Re: Share a time you realized something you are workng with is obscure.
Post by: Artlav on July 28, 2014, 08:38:37 am
Once upon a time i googled "Erasing UV eprom under power".
Nothing useful came up.

But i was still curious.
So i took an UV EPROM chip with an image, plugged it into a TV signal generator, and erased it while turned on.
The result was recorded and uploaded.

Now if you google something like "erasing eprom under power", the first result will be my video.
As far as i'm aware, noone ever done this before. :)
Title: Re: Share a time you realized something you are workng with is obscure.
Post by: bwat on July 28, 2014, 08:44:46 am
So i took an UV EPROM chip with an image, plugged it into a TV signal generator, and erased it while turned on.
Quite excellent. I'm view 980.
Title: Re: Share a time you realized something you are workng with is obscure.
Post by: tautech on July 28, 2014, 08:51:55 am
Years ago I selected an email name, based on a dream that my hobby might one day develop into a small business.  8)
That email name formed part of the URL of a small company I set up about a year ago, along with a simple website that I knocked together in an afternoon.  ::)
Promptly did the SEO and then tried to find it with various obscure searches.  :palm:

Not much luck, P10 on Google, oh well, give some time and see what happens I thought.  :-\
Quietly cursing the .za site with the same name.  :rant:
It is what it is, I mumbled..... but only the NZ market was my primary interest.

As I had a listing or two on Trademe(our NZ *Bay), thought I had better put the company name in the last line of the listing(URL's not allowed)  :-- to promote a few more hits.
As a member here, and with Dave's generous allowance of website links in ones profile, I also linked it from EEVblog.  :-+

Well, what difference a year and a few hundred thousand hits make, unbelievable.
Google 1st page for a few obscure searches now and a heap of credit goes to Dave and you EEVblog'ers.  :-+  :clap:

But still got to beat that .za site to the top of the page.  >:D

Title: Re: Share a time you realized something you are workng with is obscure.
Post by: tautech on July 28, 2014, 09:39:13 am
Round 15 years ago, I was given an old CRO, a Telequipment D83,(early 70's) 50 MHz, not going.  :-BROKE
Well I searched high and low on the net for a PDF and eventually found a guy in the UK that would sell a loose leaved photocopied version. Damn, but it was better than nothing.  ::)

Well fixed "her" up then  :-BROKE then fixer "her" again several times.  :wtf: then moved on to more modern scopes.
Thought I had better move on the "bitch"(as she was known as by then) and thought I might like to provide some lucky new owner with a CD manual(they were going to need one).  :-X

Jumped on line and what do you know, a manual could be had in several free download sites.  :o

But I will add, it had a large CRO display, fine, crisp and IMO a perfect trace and I miss her only for that.  :(
FYI Telequipment(UK) was bought by Tektronix and was eventually lost as a separate identity within Tek.
Title: Re: Share a time you realized something you are workng with is obscure.
Post by: DenzilPenberthy on July 29, 2014, 12:31:09 pm
Like T3sl4co1l above, my first job out of university was doing R&D on RF/induction heating. The main effort of what I was doing was developing a process for dielectric welding lids onto ready meal food trays. Quite fun to be in a job where you can go from never having even heard of the process before to something approaching a top industry expert with lots of patents within two years :) Big fish, small pond :)

Now I design and make one-offs for the scientists in a university physics department, *everything* I work on is obscure :)
Title: Re: Share a time you realized something you are workng with is obscure.
Post by: kc0ngu on July 29, 2014, 08:31:32 pm
Currently restoring a WWII era morse code trainer (TG34A) that used paper tape and a vacuum tube photodiode to generate the morse code.
Pictures and tear down/restore will appear on my Flickr page.
Not sure if this is obscure as such, but certainly not common.
Title: Re: Share a time you realized something you are workng with is obscure.
Post by: retrolefty on July 30, 2014, 12:08:11 am
I once tested the shock and vibration response of feminine hygiene products for an engineering application. Putting in the receipt for maxi-pads to accounts raised few eyebrows.

Wow, now that is a spot on project.  :-DD
Title: Re: Share a time you realized something you are workng with is obscure.
Post by: NiHaoMike on July 30, 2014, 12:31:08 am
I tried to find a PT chart for R433b refrigerant with no useful results. Also trying to find a generic algorithm for implementing a PT chart in a microcontroller didn't go very far. In the end, I decided to interpolate the PT chart from the PT charts of R290 and R1270 (the two compounds found in R433b), then wrote my own code to interpolate values from a constant array. It ended up being more accurate than my set of Yellow Jacket gauges.
Title: Re: Share a time you realized something you are workng with is obscure.
Post by: f5r5e5d on July 30, 2014, 01:07:20 am
I r a "Geometric Algebra" fanboy:
Quote from: f5r5e5d
I*j*k=-1 is weird - a choice of "handedness" that Gibbs swapped when he stole the name "vector" from Hamilton and gave them the present interpretation

some GA authors do appear to adopt a 3D Bivector basis with Hamilton's i,j,k handedness convention

but the uniform application of duality to get the 3 3D basis Bivectors from the now preferred 3D x,y,z unit basis vectors with "right handed" ordering swaps the signs - equivalent to saying Hamilton's Quaternion Basis choice is "left handed"

Hamilton's choice may be related to wanting the "pseudoscalar" - the highest grade element in a GA of given dimension to have a square = -1

which is the case for Euclidean 2D and 3D space, their Geometric Algebras, and (due to the mixed signature) 4D Minkowski spacetime, but not a general result for arbitrary dimension, and signature

but lacking the idea of the trivector, 3D pseudoscalar I=x^y^z of GA, where x,y,z are our normal unit vector basis for 3D and  I*I=-1 Hamilton made his choice that makes I*j*k=-1



I like Hestenes promoted Geometric Algebra for its concrete geometric interpretations of the elements, "operations" of geometry - rotation, dilation, projection...

but i r a engineer


dealing with an algebra with new "products" the dot/inner product, wedge/exterior/outer product and the "geometric" product with mix of normal and anticommuting elements, fundamental "product" which is then in general not commutative is a big step up from middle school algebra

but there are solution patterns - both decomposition, and "completeing" the "geometric product" to take advantage of its associativity, duality to interchange products...
with most multivectors in 3D GA having inverses you can do things Gibbs Vector Algebra makes next to impossible (do watch out for those nilpotents)
Title: Re: Share a time you realized something you are workng with is obscure.
Post by: marshallh on July 30, 2014, 01:16:12 am
When I kept finding bugs in USB3 compliance tools, so I had to debug the debugger with ANOTHER protocol analyzer
Title: Re: Share a time you realized something you are workng with is obscure.
Post by: Someone on July 30, 2014, 02:02:16 am
Tube oscillators from the '80s are still in wide service, and resale from time to time.  Yes, '80s -- again, tech moves slowly
Second hand? You can buy new instruments using valves for their oscillators:
http://www.chem.agilent.com/en-US/products-services/Instruments-Systems/Atomic-Spectroscopy/720-Series-ICP-OES/Pages/default.aspx (http://www.chem.agilent.com/en-US/products-services/Instruments-Systems/Atomic-Spectroscopy/720-Series-ICP-OES/Pages/default.aspx)
which has only just replaced with a product using solid state oscillator as of the last few days.
Title: Re: Share a time you realized something you are workng with is obscure.
Post by: T3sl4co1l on July 30, 2014, 02:27:08 am
Tube oscillators from the '80s are still in wide service, and resale from time to time.  Yes, '80s -- again, tech moves slowly
Second hand? You can buy new instruments using valves for their oscillators:
http://www.chem.agilent.com/en-US/products-services/Instruments-Systems/Atomic-Spectroscopy/720-Series-ICP-OES/Pages/default.aspx (http://www.chem.agilent.com/en-US/products-services/Instruments-Systems/Atomic-Spectroscopy/720-Series-ICP-OES/Pages/default.aspx)
which has only just replaced with a product using solid state oscillator as of the last few days.

Ha, awesome.  To be fair, it is hard to match the mismatch and overload tolerance of toob tech.  Plasma is a notoriously bad load to match into; one instant it's open circuit, the next it's nearly a short.

Tim
Title: Re: Share a time you realized something you are workng with is obscure.
Post by: Tinkerer on July 30, 2014, 03:56:50 am
I once tested the shock and vibration response of feminine hygiene products for an engineering application. Putting in the receipt for maxi-pads to accounts raised few eyebrows.
So whats the story behind this?
Title: Re: Share a time you realized something you are workng with is obscure.
Post by: T3sl4co1l on July 30, 2014, 04:26:40 am
I once tested the shock and vibration response of feminine hygiene products for an engineering application. Putting in the receipt for maxi-pads to accounts raised few eyebrows.
So whats the story behind this?

Probably a good damping element (in practice, you'd normally use a felt pad or something like that, I imagine) -- the mechanical equivalent of a ferrite bead (after all, shock and vibe is literally the mechanical analogy of ESD and EMC testing).  That would be my guess, anyway. . . .

Tim
Title: Re: Share a time you realized something you are workng with is obscure.
Post by: calexanian on July 30, 2014, 06:07:38 am
My main induction heater here at the house for making my small tubes is a 2.5 KW Lepel from 1986. Its a beautiful machine. It uses 3 triodes with no numbers on them. I believe they are variants on the 810 triode. Still works like a champ! Down at the tube factory in Oceanside there are several units the owners dad built in the 60's revolving around wither the common 833 circuits of the time for the small ones, and some super crazy high power EICO generators for hydrogen environment brazing and the bombers for tube exhaust that use a 2X2500 each. THey will raise two anodes of 6303's at a time all the way up past orange heat if you crank it up, and will hold them at bright red heat indefinitely. Some of the new line tied small form factor heaters are interesting, but load matching is far more critical. The tube ones when there is no work piece in the coil they are ok generally, and just a total load, such as a nickel cylinder presents no problem going from those extremes.
Title: Re: Share a time you realized something you are workng with is obscure.
Post by: David Hess on July 31, 2014, 03:18:37 pm
When I was designing low noise low drift DC amplifiers, I needed a way to verify and set the frequency break point between the low noise amplifier and the chopper stabilized amplifier used to control 1/f noise and drift for lowest total noise from DC up to a few Hz.  An AC measurement would not work because its frequency response would not extend low enough so what I ended up doing was using my best multimeter, something like a Fluke 8505A, in sampling mode measuring the DC value and then calculating the standard deviation of the samples taken over 10 seconds which is conveniently the RMS value of the noise over the input bandwidth.  If I ever design a multimeter, I am going to include a function to make this type of measurement.

The frequency break point was adjusted by setting the integrator gain so once I found the value for the lowest total noise, I went back and calculated the frequency break point and compared it to the low frequency noise curves for the separate amplifiers and found it to match exactly what was needed.

That low noise amplifier ended up working so well that it could be used to measure low values of resistance by thermal noise alone.