Test Equipment Anonymous (TEA) group therapy thread

[mnementh]

[Random Mode]

[Things that make you go  "Hmmmm..."]



So this morning (barely) I wake up in a fugue state after futzing around with my new Tornado 3DP until almost 5AM; after the obligatory scratch, yawn and grumping at my noisy kids who woke me up so rudely at the crack of noon, I decide to get up before I turn 100% vampire and start living the graveyard shift. Rummaging around in the laundry basket for clean socks and shorts I come across this disturbing little penguin creature that for all the world looks like a miniature sex doll complete with pouty lips and "orifices". 

Persisting mental fog notwithstanding, the REALLY disturbing thing about it (to ME at least) is the fact that nobody in my house knows where it originated from or how it came to be lurking in my UnderArmor pile. Not me, not my wife or either of my children. NOBODY.   


[/Things that make you go  "Hmmmm..."]


[3DP Time]




For those still interested in the ongoing saga of The 3D Printer That Actually Worked, here's a quick photo rundown of this morning's fettling. (Yeah, I'm deliberately trying to wear that word out; it has ALMOST gotten to that point of having lost all meaning.  )

First up is a closeup of the part showing the hollow infill honeycomb; I was able to get some nice pics during printing and I thought it was interesting. 

Next is the spool holder just after I woke up and pulled it from the hot bed; this required some considerable prying with my thin-bladed paring knife (if you don't already have one of these Mundial restaurant-gear paring knives in your tinkerer's toolbag, they are a MUST; they have the perfect combination of high-quality stainless steel and "just-flexible-enough" thin cross-section edge for a zillion tasks) as the Tevo hotbed skin has quite good adhesion. I need to ask in the groups and see if there's some trick to make it release; I vaguely remember some post back in my Tevo Tarantula daze about heating the bed real quick then spraying the part with frost from an upended can of canned nitrogen duster. I'd have tried it already, but the bed underneath is ceramic glass like a smooth electric cooktop.

Next is a shot of the bottom showing the excellent bonding of first layer strands and how thin the trimmed-off raft is.

The next two are shots of overhang performance and conical buildup performance; layering is precise and even, and minimal slubbing at the extreme outer edges of the overhang. I could spend days tweaking and never get it any better; I'm dead chuffed with this.

Next after that is a shot of one of the gusset areas showing compound curve rendering performance; layering is mostly quite even with a few microscopic voids in the finish layer that could be tweaked out, or could be better fixed with a second finishing layer in the model. I'm not sure which is the best approach there, or if it is even worth attempting to fix.

And last is a shot of the bottom "parting area" of the print; the leftmost 1/3 is untouched, the middle third is just lightly going over it with heat from my old Ungar heat-shrink gun, and the rightmost 1/3 is working the heat until it polishes to a high gloss and removes the knife marks from trimming the raft/flash around the edges.

The middle third is easiest to do well; just a few seconds with the heat at medium distance takes away the frosted look and leaves a satiny finish, and it is easiest to do evenly. The last third requires patience and a steady hand as you have to apply the heat quite closely in a circular motion; getting an even gloss finish without bubbling or sagging the surface requires a lot of concentration. And as I discovered, the amount of heat needed to get that gloss finish across the entire surface invites the part to warp and twist; I had to manually flatten the part before it cooled. 

Okay, okay... I know I need to wrap it up before the Langoliers come to spank me for being grossly OT; I'll try and keep future updates a little less... uber.

[/3DP Time]

[/Random mode]



And now for something completely... TEA-related. 

Whilest shopping in the Micro-Center for Filament, I found myself in the midst of a wall of HDDs of varying sizes and description. in the middle of all that was a small sale flag, advertising the above SSD for the princely sum of $24.99. I wibbled over it for several minutes; I already have a hybrid HDD in my desktop and a Samsung 850 EVO in my old laptop, but damn... a SSD for $25, and something with semi-decent specs and barely usable size, not some idiotic antique like the 32GB mini-PCIE ones everybody's trying to unload in Chromebooks. I guess my son's new ThinkPad is gonna get a little turbo boost. 

After I got it home I committed a little Guugle-Fu on the beast; to my surprise, it's also available for the same price from Amazon, and for $20 more you can double the size. Not only that, the reviews are mostly positive; while not a thoroughbred performer, still a good solid SSD and crazy good bang:buck ratio.

So there... I CAN post something at least moderately TEA-related. 


mnem 

[bd139]

Note the decoupling caps everywhere.

Life's too short to watch most videos; they don't even appear in my default browser settings.

This wasn’t precautionary but reactive after there was some oscillation in the integrator stage.

Tee hee. Never doubt my judgement

I could have done it dead bug to be honest, got enough parts stock, but I want this to go nuts. Diagnosing stability problems and oscillation was one of the points of the exercise. At one point it was going mental and slinging it’s shit all over the place but now I know why and how to squash those problems.

Debugging problems with your design is fun and laudable. Debugging problems with an avoidably shitty implementation of your design is simply perverse.

But then you are a softie in financial services, so that's probably standard operating practice in your day-to-day "professional" environment Me a cynic? Shurely shome mishtake.

No comment about financial services software. It’s why I keep a roll of 20s around and a crate or two of beans

Remember if you can debug your own avoidably shitty implementation you can debug the whole spectrum of shitty implementations without pulling a face like you’ve had the shitty implementation rammed up your butt. Thus putting yourself on the top of the food chain when it comes to flames coming out of something. My software side business model is basically being paid to do things no one else will touch with a 6 foot long stick. The sick perverse person in me likes arguing with this stuff.

I have never lost. Yet.

[bd139]

@mnem that is looking pretty awesome. Not bad for the turnaround time so far on set up. I’m at +25 now

I wouldn’t use a computer without an SSD these days. No mechanical disks here other than in my NAS box and that’s only because I didn’t pay for that

[Specmaster]

@mnem that is looking pretty awesome. Not bad for the turnaround time so far on set up. I’m at +25 now

I wouldn’t use a computer without an SSD these days. No mechanical disks here other than in my NAS box and that’s only because I didn’t pay for that

I got a 500GB SSD as my main drive but then thats followed up with a 2 mechanical drives totaling 3.5TB with loads of other USB drives totalling at least another 4TB and a further 5.5TB in 3NAS drives but not all of them are in use all the time.

My laptop also has a 500GB SSD main drive and a mechanical 500GB 2nd drive in the expansion bay. If I could I'd go SSD all the way.
No reason not to have that many drives when so many can be had for fuck all from Sky+ boxes that people dump. 

[Specmaster]

@mnementh  I watched a video of your Misfit watch last night and it does have pretty good robotics and it is so much more subtle about being a smart watch than the digital ones are and that year long battery life is a big improvement too.  That said, it does still has functions that are not really necessary as they are duplicated on the phone and the phone has to be in the close proximity to you anyway so may as leave those functions to it.

It is a watch that I would certainly wear because of its quirky way it tells the date etc and it does look good as dress watch.

This watch here is one that I have and others in a similar vein from Citizen.

[Specmaster]

Heres a heads up if anyone is looking for a workbench and has the space then one of these might fit the bill?

https://www.ebay.co.uk/itm/232804674862?_trksid=p11021.c100851.m5053&_trkparms=aid%3D222007%26algo%3DSIM.MBE%26ao%3D1%26asc%3D20170803121420%26meid%3D2f91684b835d4b8cb5d6ea9fd0a0c02b%26pid%3D100851%26rk%3D1%26rkt%3D1%26b%3D1%26sd%3D263777376962%26itm%3D232804674862&ul_noapp=true

[bd139]

I reckon you could put a £20 offer on that and they'd take it 

I would grab one if I had the space to be honest.

[Specmaster]

So would I but sadly I don't have that space. Its a lovely bench though, still not enough power outlets.

[bd139]

I reckon you could plug a socket block into a each outlet 

[Specmaster]

You could but it actually has 14 blue and 4 black sockets and if the network and telephone plates were removed then an extra 6 sockets would be possible with a switch at the left end for the built in, under shelf lights. That seriously is a nice work space,

[med6753]

Definitely nice benches. I don't have the room either.

You guys still wear watches? I was never big on wearing them anyway and mine were always cheapies. But when I got a cell phone (Both dumb and smart) the watches went into the drawer never to see the light of day. 

[tautech]

Nah, they're not strong enough to support all your old boat anchors !   

[BravoV]

That mains power rails and the sockets cost a fortune when new. 

[BravoV]

The TEA devil keeps coming ... 

Guys ... how much is a good shaped, working fine Agilent 34401A worth for you ? Say easy, local pickup price, so no shipping cost. 

Upper limit ? Sweet spot ? Lower limit that you would not think twice with above conditions ?

Guys ... any hint please ?

[Specmaster]

Definitely nice benches. I don't have the room either.

You guys still wear watches? I was never big on wearing them anyway and mine were always cheapies. But when I got a cell phone (Both dumb and smart) the watches went into the drawer never to see the light of day. 

Yep still wear watches, ever tried reading a smart phone outside in brightshine, especially when wearing polarised sunnies?

[med6753]

Nah, they're not strong enough to support all your old boat anchors !   

I wish I had a genuine boatanchor. Sadly at this point I don't but always looking. I know there's a 535, 545, or 547 out there for the right price with my name on it. Even a 561A/B would satisfy that craving. The closest to boatanchor status that I have right now is the OS-245 (7603N) and it's on it's own cart. But it's not vacuum tubes. The only tube stuff I have at the moment is a Heath VTVM.

[Specmaster]

Nah, they're not strong enough to support all your old boat anchors !   

Of course it is, many are now sitting on nothing more than a wooden shelf and 3 more sit on a small computer table, so yeah, I'd be happy to mount them all on the shelf of that bench, no worries mate 

[bd139]

The TEA devil keeps coming ... 

Guys ... how much is a good shaped, working fine Agilent 34401A worth for you ? Say easy, local pickup price, so no shipping cost. 

Upper limit ? Sweet spot ? Lower limit that you would not think twice with above conditions ?

Guys ... any hint please ?

I'd pay £300 (GBP) for one.

[Specmaster]

Bah, my cheap arse SMPS bench power supply has decided its going to introduce mains hum to my speaker system, switching to my linear bench supply and the hum's gone. May to look out for another cheap linear supply, that hum is driving me mad.

[Berni]

Nah, they're not strong enough to support all your old boat anchors !   

That bench looks plenty strong enough to hold boatanchors with its steel tube frame.

Whats likley more of a problem is that the top shelf is too shallow for boatanchors as they often tend to need over 40cm of depth.

[Specmaster]

No problem to screw another deeper piece of board on top of the one thats there.

[BravoV]

The TEA devil keeps coming ... 

Guys ... how much is a good shaped, working fine Agilent 34401A worth for you ? Say easy, local pickup price, so no shipping cost. 

Upper limit ? Sweet spot ? Lower limit that you would not think twice with above conditions ?

Guys ... any hint please ?

I'd pay £300 (GBP) for one.

Ok, thanks, and this DMM price still relatively high isn't it ?

[Berni]

Bah, my cheap arse SMPS bench power supply has decided its going to introduce mains hum to my speaker system, switching to my linear bench supply and the hum's gone. May to look out for another cheap linear supply, that hum is driving me mad.

I have had a fair few bad experiences with cheap SMPS supplies.

We have some Blanko brand ones at work:


One of them we killed 2 minutes after powering it on by putting a ampmeter across the output and slowly cranking it up to see if it actually can give the specified 10A. We got to about 7A before it suddenly turned off and would never power on again so we returned it.

Next one we got worked fine and could give 10A without blowing up, but after 3 months of being plugged in it suddenly caught fire inside, upon inspection the mains EMI filter capacitor was all chard black.

Another one we used in the lab to run some heavy load while i was doing some EMI testing on the other side of the room. When a coworker turned on the Blanko piece of crap i suddenly had my spectrum analyzer start making a angry beeping sound signaling that its mixer is overloaded.

I would not own this piece of shit even if i was given one for free

[bd139]

If you only need an amp, these are on offer on CPC: http://cpc.farnell.com/aim-tti-instruments/el301r/power-supply-30v-1a/dp/IN0576761

£100 aint bad.

Economy option: http://cpc.farnell.com/tenma/72-10480/power-supply-1ch-30v-3a-adjustable/dp/IN0682261

Same unit as a Korad 3003D.

[bd139]

The TEA devil keeps coming ... 

Guys ... how much is a good shaped, working fine Agilent 34401A worth for you ? Say easy, local pickup price, so no shipping cost. 

Upper limit ? Sweet spot ? Lower limit that you would not think twice with above conditions ?

Guys ... any hint please ?

I'd pay £300 (GBP) for one.

Ok, thanks, and this DMM price still relatively high isn't it ?

Yes. Last DMM they made before OLED crap started appearing at the high end.