EEVblog #936 - Mailbag

[EEVblog]

Old component bonanza Mailbag!




SPOILERS:
TI-74 BASIC pocket computer teardown from 1985
OpenMYR WiFi Motor Kickstarter
https://www.kickstarter.com/projects/77886650/wifi-motors?token=9aa90ab1
Several 4-banger calculators
GEZE automatic roller door controller teardown
E-Book reader teardown and PCB bypassing techniques,
http://www.switchandlever.com

[Andy Watson]

Ace! Love to see more research on the glassware stuff.
I'm pretty sure the first unknown piece was a Dekatron, or similar counting device.

[jonovid]

Ace! Love to see more research on the glassware stuff.
I'm pretty sure the first unknown piece was a Dekatron, or similar counting device.

geiger counter type tube    9:55

Dekatron Counter Tube    7:15

[McBryce]

The metal/glass component at 12:55 is an LDR (Light dependent resistor) as used to switch on street lights.

McBryce.

[cj]

The tube at time index 7:17 looks a lot like a “leuchtquarz”, translated light emitting quartz crystal. If the quartz is resonated with sufficient amplitude it should light up just like a small neon bulb.

The tube at time index 9:47 is definitely a photomultiplier.
A Google search results in type numbers FS9-P10F, FS9-P10S, VFS950F or VFS910F

I have a small collection of similar glassware. It’s always interesting to see what they used to put in vacuum or gas filled tubes.

CJ 

[bktemp]

The tube at time index 7:17 looks a lot like a “leuchtquarz”, translated light emitting quartz crystal. If the quartz is resonated with sufficient amplitude it should light up just like a small neon bulb.

Very interesting. I have never seen a quartz crystal combined with a neon bulb before.
They seem to need quite some power (50-100V at the correct frequency (<0.1%) to light up. You can even see multiple dots when driven at harmonics.

Maybe it is time for a followup video playing with those tubes. It would be probably the first video on Youtube showing a working "Leuchtquarz".
Some of the tubes should be pretty easy to drive (like the filament displays). The dekatron needs some more circuit to make it counting, but it would also be interesting.

SEL is short for Standard Elektrik Lorenz, a former German electronics manufacturer. But Dave is right, the device is a selenium rectifier (rated for 60V 300mA).

What is the device at 10:30 and the device at 13:00?

[jonovid]

The tube at time index 9:47 is definitely a photomultiplier.
A Google search results in type numbers FS9-P10F, FS9-P10S, VFS950F or VFS910F

  geiger counter type tube    9:55  I stand corrected    Yes its a photomultiplier I now see the number of pins on it.  had advertising for photomultiplier tubes in my Dad's Electronics Australia EA magazines.  as for the WiFi Motor , Open Source platform that anyone can use.    our pets can do with WiFi controllable feeders. if Chinese hackers over feed the cat will it be a catastrophe   

[NivagSwerdna]

35:00  I think he's trying to tell you he knows where his towel is.

[dexters_lab]

...and the device at 13:00?

struggling on that one too, interesting though the number of pins match the row and column count

come on Dave... extreme teardown time!

[rollatorwieltje]

It's this thing: http://www.radiomuseum.org/tubes/tube_dm12-9-3.html

Diode grid for driving a display using DTL.

[bktemp]

It's this thing: http://www.radiomuseum.org/tubes/tube_dm12-9-3.html

Diode grid for driving a display using DTL.

Interesting. Time for extreme teardown.
It would be interesting to see how they packed all the diodes into that module. Is everything on a singe chip, or did they use individual diodes?

[PA0PBZ]

This smells 

https://commons.wikimedia.org/wiki/Special:Contributions/Binarysequence

"Own work" sure, getting the screenshots from YT. And there's more further down the list.

[rollatorwieltje]

This smells 

https://commons.wikimedia.org/wiki/Special:Contributions/Binarysequence

"Own work" sure, getting the screenshots from YT. And there's more further down the list.

Yes, Dave is ripping off his own videos 

All those pictures have the exif information of his camera, a screenshot of Youtube wouldn't have that.

[PA0PBZ]

Yes, Dave is ripping off his own videos 

WTF... Binarysequence is Dave? Someone should have told me that before I made a fool of myself! 

[drjazz]

the item at 11:30 is a selenium bridge rectifier


http://www.semicon-data.com/diode/dsl/B30C600.html

[MartinX]

The Hugin calculator is not made in Sweden it is rebranded by Kooperativa Förbundet, Hugin still is one of their labels, I have a Hugin branded vacuum cleaner. The label says "IMP" in the corner, that is not to offend short people it stands for imported, it is probably made in Japan.

The only Swedish company to make calculators in any numbers were Facit as far as I know and they didn't last very long, the Japanese manufacturers totally killed them.

[TassiloH]

It's this thing: http://www.radiomuseum.org/tubes/tube_dm12-9-3.html

Diode grid for driving a display using DTL.

Interesting. Time for extreme teardown.
It would be interesting to see how they packed all the diodes into that module. Is everything on a singe chip, or did they use individual diodes?

I remember that I took one apart as a kid. I vaguely remember that the plastic contained stamped metal contact strips for the matrix, and at each connection point a little spring and something too small to identify (probably the diode as bare die, or point contact diode formed together with the spring).

[tzok]

I have a very similar calculator, but mine is from Germany (probably West Germany), and is a simple "four-banger". It is MBO branded, "de Luxe I" model:


I've also found a photo of MBO de Luxe IV, which is identical to one on the video... so apparently it was some "generic" calculator sold under different brands around the world.

[Halcyon]

One of those tubes (at 6:43) looks like a video camera tube (or Vidicon tube).

[bktemp]

It's this thing: http://www.radiomuseum.org/tubes/tube_dm12-9-3.html

Diode grid for driving a display using DTL.

Interesting. Time for extreme teardown.
It would be interesting to see how they packed all the diodes into that module. Is everything on a singe chip, or did they use individual diodes?

I remember that I took one apart as a kid. I vaguely remember that the plastic contained stamped metal contact strips for the matrix, and at each connection point a little spring and something too small to identify (probably the diode as bare die, or point contact diode formed together with the spring).

Sounds like the matrix is easily "reprogrammable" by rearranging the diodes.

[rrinker]

 Only if your name is Neo 

[PA0PBZ]

Only if your name is Neo 

 

It sounds more like "Once you open the unit the diodes will jump out all over the place and you're screwed"  but if anyone wants to try...?   

[Alex Eisenhut]

OOooh, love those flatpack ICs in their colorful plastic holders! Betcha those are Philco.



Man I'd love a few of those chips. One to crack open and look inside.

[fusebit]

I like the filament display, they look nice in operation!

[CoolKoon]

Just an FYI for the Tesla branded chips (visible around 6:07): they have been made by THE electronics (both consumer electronics and parts) manufacturer in Socialist Czechoslovakia (the only such company and state-owned as everything else) named after the Serbo-Croatian-American inventor Tesla. Their product range was pretty impressive (minus more complex ICs, most of which had to be "imported" i.e. smuggled in from western countries), their specs less so. IIRC the company was privatized after 1989, with some divisions going bankrupt afterwards and some remaining, but AFAIK the Tesla brand has not been used by them for at least 15-20 years.