What did you buy today? Post your latest purchase!

[DrG]

Only US$50

Need something to do while they count votes.

To follow up and in case anyone else is interested or thinking about android programming. I did get around to starting to play with this. It is pretty junky in the sense that it seems to be a 100% Google monstrosity (took 10 minutes to figure out where setup was to get to a screen for USB debugging).

I installed Android Studio and went through the tutorial here: https://developer.android.com/studio/write/layout-editor#intro I kept getting an error in the final app. I rebuilt it from scratch three times (which was actually a good learning experience) but still could not figure it out. I knew that a reference was off but I did not appreciate what an id is (I still may not). In this regard, I think the the tutorial is either outdated or unclear or wrong. Before building it a fourth time, I searched on the error and found this https://stackoverflow.com/questions/45377621/error-cannot-resolve-symbol-edittext-in-android-studio-myfirstapp-tutorial which was not a turnkey fix but was enough information to successfully complete and run the app.

I spent almost as much time getting a USB driver to run and work on an old Win7 box. Seems like I spin the same wheels every time eventually beating it into working.

The screen is nice. I have yet to root the machine but I only tried once (KingoRoot).

I never did anything with Android programming before so I can only say that if you want to get your feet wet, this worked for me. Not sure I even know enough yet to recommend Android Studio but it does work. Kotlin or Java - dunno, I went with Kotlin so far.

We'll see, next up (at least on the list) is to find some BLE devices.

[gamalot]

Olympus E-M10 Mark IV 

[Ed.Kloonk]

Olympus E-M10 Mark IV 

Nice.

[TerraHertz]

A pretty good test of whether the USA will have a general truckers strike or not. A couple of HP catalogs, recently departed from Forked River, NJ, on their way by road across the continent to LA.

They are the 1993 and 1996 editions. Gradually building my set. Currently:

[IDEngineer]

Those hardbound HP catalogs were my Christmas list every year as a kid. Santa never came through, sadly.

[Ed.Kloonk]

Those hardbound HP catalogs were my Christmas list every year as a kid. Santa never came through, sadly.

Should have waited for the following year to call out the drunken old fool. Chuck a tanty and punch him in the balls.

[Cubdriver]

A pretty good test of whether the USA will have a general truckers strike or not. A couple of HP catalogs, recently departed from Forked River, NJ, on their way by road across the continent to LA.

They are the 1993 and 1996 editions. Gradually building my set. Currently:

Ahh yes.  Crack catalogs.  May their travels be uneventful.

-Pat

[Microcheap]

I didn't pay attention and didn't followed the official links so I ended up with a cheap clone TinySA "Spertrum" Analyzer that won't pass self test and don't have the internal shielding. Maybe it was damaged by "static disqharge" 

And a somewhat better quality tool to make sure my beer is at the right temperature:

[_Wim_]

Just search fiber laser engraver on YouTube, and I don't see many use this in an enclosure.

FYI, those are marketed in China for use in the open public, for engraving souvenirs on street side markets or tourist destinations.

Sounds scary, but so far no reports stating they have blinded anyone.

Again, I need to stress the fact that those lasers are NOT collimated. They use a technology called f-theta lens, which allows for large area engraving without losing focus.

Essentially, the more the light bends, the longer the focal length is, so effectively at the same vertical distance it is always in focus, regardless what the hypotenuse length is.

However, once the vertical distance changed, it goes out of focus very quickly.

Typically you get ~3mm of travel before the laser loses enough focus and loses capability to do any damage to even organic matters, and for metal engraving, ~1mm, and I will be at least 30cm from it when it runs.

Before the F-theta lens you have a collimated but expanded beam (expanded to protect the galvo mirrors from burning in due to the very high peak powers), and the F-theta lens refocusses the expanded beam exactly at the same height everywhere on the working area of the lens. Due to the very fine focus the peak power / area is enormous, which causes the material to vaporize.

If for example the beam before the f-theta lens has a diameter of 8mm, and the working distance of the F-theta lens is 200mm, then the reflected beam will have again a diameter of 8mm at 200mm reflected distance.  Remember these laser can generate pulses in excess of 10kW, which takes quite a distance for attenuation even if the beam is not very collimated. Laser safety glasses typically of an OD of >6 (attenuation of 1 million) for a good reason!

I can imagine as long as the engraved object is perfectly flat, this probably creates no major issues as the beam is reflected back towards f-theta lens. But if the marked object only slightly refocuses the reflected beam is your direction, I cannot imagine safety is always guaranteed.

Apart from videos on youtube, I have never come across one in industry without a safety cage. Agreed, I have not seen hundreds of laser marking machines in my job, but I have come across at least 25 of many different brands. That why I asked if you are aware of any datasheet from a reputable company that states one of their products can be used without a safety cage. 

I would still recommend to be careful, and to use a good quality pair of laser safety glasses for you and anyone nearby.

[DrG]

I didn't pay attention and didn't followed the official links so I ended up with a cheap clone TinySA "Spertrum" Analyzer that won't pass self test and don't have the internal shielding. Maybe it was damaged by "static disqharge" 

I looked into that as a result of your post. I looked into the genuine TinySA (genuine spelling of spectrum). It's only US$50! This, right? http://www.randl.com/shop/catalog/product_info.php?products_id=75243&osCsid=ha9cd162ojp4v041la6a18bv47

Very cool. I am thinking about it as a holiday gift...for myself...not that I really have a need for one, but still..

[Ground_Loop]

Got my hands on a fine Starrett tap handle.

[rfclown]

Hard to resist the cheap Chinese stuff. I've got an decent HP counter, but with a crap reference, so I use an external ref. Wanted a second counter for my day job (since my employer has only one counter for many engineers, and no good reference). I was going to build one, but saw this on eBay, and it wasn't worth the time making a better one. The reference alone in this thing is something I get $25 bucks for on eBay, and the counter was $130 shipped from US. It's a BG7TBL FA-2. As received the internal reference was only 0.11 Hz different than one of my rubidiums. Tweeked the adjustment pot to bring it closer.

[Gary350z]

HHIP 4401-1597 Granite Surface Plate for checking flat things. $41 from amazon with free shipping.
Not top of the line, but good enough for me.

[Syntax Error]

Paint the Whole World with a RAINBOW DIP Switch. Or two.

Part No: ERG_SDS-8-023

[I wanted a rude username]

Love the fact that the colours match up (presumably intentionally) with those of a standard rainbow ribbon cable.

[Ed.Kloonk]

Love the fact that the colours match up (presumably intentionally) with those of a standard rainbow ribbon cable.

If birds fly...

[IDEngineer]

HHIP 4401-1597 Granite Surface Plate for checking flat things. $41 from amazon with free shipping.

Wow, that's actually a great deal if the accuracy is as claimed. I might have to get a stronger Christmas stocking.

[Calambres]

Just ordered this beauty:




An RPN queen for sure!

[richnormand]

@Calambres

Drooling...... and envy

Still using my HP33E on the bench so I should not complain too much.
RPN rules.
Too bad most engineering graduates I meet have no idea. On the other hand, my calculator does tend to stay on my desk and they are stunned I finish a calc sooner than they do.

My SO has to one with the magnetic cards and that still works too.

[IDEngineer]

RPN for the win! I have three HP10 series calculators on my desk, my wife uses 12C's exclusively, and I think I still have my original HP35 and HP55 in a box somewhere.

EDIT: Almost forgot the HP11 emulator on my OnePlus cellphone, too.

Someone once asked to borrow one of my HP calculators. I waited for the inevitable "Where's the equal sign?", then told them it was in the battery compartment. Being one of the original series, its triple-NiCd pack fell right out... depowering the calculator... yet they still searched in the compartment for the equals key.

RPN everywhere, all the time. Accept no substitutes.

[Mr.B]

A handheld spectrometer (380nm to 780nm)



https://www.aliexpress.com/item/10000399579584.html?spm=a2g0s.9042311.0.0.5e904c4d95N1up

[Gary350z]

HHIP 4401-1597 Granite Surface Plate for checking flat things. $41 from amazon with free shipping.

Wow, that's actually a great deal if the accuracy is as claimed. I might have to get a stronger Christmas stocking.

With amazon you get free shipping and FREE RETURN SHIPPING so you can't go wrong.

...and your wife says you got a rock in your Christmas stocking.

[Gary350z]

tinySA spectrum analyzer for $50
I ordered it today from Aliexpress.
Frequency range from 100kHz to 350MHz
Be aware it is small (screen diagonal 2.8"), and has limitations.

Information:
https://tinysa.org/wiki/pmwiki.php?n=Main.HomePage

Only buy from official stores to avoid clones:
https://tinysa.org/wiki/pmwiki.php?n=Main.Buying

[IDEngineer]

...and your wife says you got a rock in your Christmas stocking.

I could argue that a Granite Surface Plate IS a rock in my Christmas stocking! 

[coppercone2]

yea put some 4000$ pink granite parallels in the stockings from starrett

I got a 4 inch thick pink starrett one could make a good valentines gift or something



I would try but I think the weight limit is like 100lb.

I do think that since I have had it the molding in the house looks off and it slightly annoys me.

the pink is supposed to be a better surface that does not stick so much IIRC.