What did you buy today? Post your latest purchase!

[CharlieWorton]

Hi, tautech - yeah, it occurred to me that I could slide a sacrificial board under the pcb, and let it splinter instead of the pcb.  I think that might help.  But truthfully, I think that the bandsaw was a bad idea to begin with.  I need to find a better solution.  Still, I do think that a narrower blade gap would help minimize breakout.  Thanks - Charlie

[MatthewEveritt]

I dunno.  It is true that I must have taken a vow of poverty in my youth, which accounts for my living under a bridge.  (But it's a very nice bridge).  But $100 doesn't seem cheap to me.  If you know of a cheaper way to get boards, please let me know.

Have a look at pcbshopper

[jonovid]

Just got in this. electronic event counters or sold as muslim prayer counters.
I will use then for testing anything needing a count.  just solder two wires on to the pcb & add a switch.

remember this video.
no need to rip up a 5 dollar calculator, when you have 1 dollar event counters
EEVblog #962 - Hacking A Calculator Into A Counter

[CharlieWorton]

As always, you folks are an incredible source of knowledge and wisdom.  I genuinely appreciate the help.

Blueskull, thank you for the offer!  That's wild, that someone on the board would live exactly there.  I'm still hurting from having spent $150 on a saw I won't be using, so I don't think I'm going to buy anything new.  Instead, I think I'm going to work at using the tools I already have.  But i appreciate the offer, and if my circumstances change, I'll drop you a line.  Thanks again.

MatthewEverett, cleaningOut - I'll check out pcbshopper and dirtypcbs.  After spending all this cash and effort on equipment and supplies to make pcbs, if it turns out that I can buy them just as cheaply...  well, sigh.

The blade gap on the bandsaw is large, around a quarter inch.  But... hey!  I own a 3D printer!  Exactly the kind of job it's really good at doing.

Something else I'm thinking about is making a guide to fit on the base of the dremel workstation, putting a milling bit in the dremel and using that to cut pcbs.  I would think it should yield a decent cut.  Another project for the 3D printer.

So last Thursday I visited a couple friends of mine on their acreage.  They're both getting on in age, he's had a heart attack and a quad bypass, and now uses a walker for anything outside their home.  So they want to sell the acreage and buy a condo in Victoria, B.C. where they'll live out the remainder of their lives.

So, they're in 'dispose of all this junk' mode.  His wife had a hewlett packard 2000 series laptop and an officejet 8500A multi-function printer, wasn't using them...

They drove home in my back seat.

The laptop isn't anything special; core i3 architecture from several years ago, 500Gb drive, 4Gb ram, 15" screen.  But it's a good 'surf the web' machine, and having an extra computer available never hurt anyone.

Similarly, the officejet 8500A wouldn't be my choice of printers; I hate inkjets.  And, the power brick that runs it had somehow gone missing.  But it does have a scanner/copier function with an automatic document feeder, it will print on both sides of a sheet of paper, and it connects via wifi.  So I found a cheap Chinese power supply on Amazon, complete with the funky HP patented plug.  While I was there, I ordered some ink cartridges.  The power supply showed up yesterday, the ink today... and after a ridiculous amount of ink spent cleaning the heads, it's up and working.  Got the latest firmware installed on it, so hopefully it will behave itself.

The officejet might prove useful in making transparencies for making pcbs; people complain that the laser printers put out too thin an image, that the blacks are grey rather than black.  Possibly the inkjet will do a better job.

Oh, and the other thing I purchased was a Wen rotary tool kit.  Got the tool, a flexible extension, a bunch of missc. bits and fittings, all in a tidy black plastic case... cost me a grand total of $28.  At that price, heck.  You can't have too many rotary tools.

Take care, all - Charlie

[McBryce]

Just got in this. electronic event counters or sold as muslim prayer counters.
I will use then for testing anything needing a count.  just solder two wires on to the pcb & add a switch.

remember this video.
no need to rip up a 5 dollar calculator, when you have 1 dollar event counters
EEVblog #962 - Hacking A Calculator Into A Counter

I tried the hack with a Catholic prayer counter, but it doesn't work as well

McBryce.

[jonovid]

Just got in this. electronic event counters or sold as muslim prayer counters.
I will use then for testing anything needing a count.  just solder two wires on to the pcb & add a switch.

remember this video.
no need to rip up a 5 dollar calculator, when you have 1 dollar event counters
EEVblog #962 - Hacking A Calculator Into A Counter

I tried the hack with a Catholic prayer counter, but it does work as well

McBryce.

google prayer counter & see for yourself.    seriously they used for that! 

cheap electronic event counters are going to go to sleep in just 12 minutes.
with a blank lcd screen. however its the dead count that is needed to wake it up.
so if the counter is 101 when it gos to sleep. it will sill be 101, when its wake it up. not 102,
even though the count button was pressed, making this event counters not suitable for count cycle lengths greater 10 minutes between counts. also with disassembly the lcd screen module with its conductive rubber strip will separate from the pcb without the case to hold it in place.
so if your considering hacking this cheap event counters take note.

[Bendba]

It finally arrived, from Ukraine.
Two "new old stock" (indeed new, the plastic was still sealed) 30W pulsed IR diodes. Tested and with original datasheet, with matching number.

Datasheet says they are minimum 30W light output at a 40° cone. And then, test data says one tested 133.3W and the other 96.1W. Sweet!

Just gotta work out a driver and how to colimate and then focus them. And see what that can engrave/cut

Edit:

If I translated it right, it takes 100+-30 ns pulses at max 8 to 11A and max 500+-50Hz
I guess I'm not driving it with a pair of coin cells and a small resistor 

[Bendba]

No, they are not for high average power (that would be too good, for $20
Maximum duty cycle is 0.5%

I didn't really buy them for cutting or engraving, really, I just want to try to see what they are capable of.

I want to try to make a long distance line of sight data transceiver, just for the fun of it.

[julianhigginson]

I went on a mini End Of Financial Year rampage the other night using a 15% off ebay voucher and picking up a couple of things I'd had on my watchlist for a while...

Now I have a simple cheap as all hell board preheater, a (surprisingly solid seeming compared to what I was expecting) hot air iron stand, and I'm waiting on a small Panavise setup to arrive.

[Bendba]

Laser diodes follow up.

Well, I've either been ripped off or I'm missing something.
I went to measure the village do voltage drop of the diodes, they both appear as a dead short, no voltage drop and no resistance on the ohm meter.

Any idea of what I'm missing? Or did I just received two duds? That'd be surprising, it's from a usually very good seller.

[Bendba]

I went to measure the village do of the diodes, they both appear as a dead short, no voltage drop and no resistance on the ohm meter.

Swift keyboard to its finest.

High power LEDs and LDs can be damaged VERY easily by ESD. After decades of being non ideally stored, it's not that surprised to see them being killed.
Modern ones are more resilient, such as the one I showed in my video, but there's a 30 years technology gap.

Yes, that's what happens when you forget to check messages before sending them.

That's a bugger, I've been as careful as one could be while opening the package because I was expecting them to be sensitive to ESD's
They even had a piece of cardboard protecting the pins from being in contact with the plastic.

Is it likely that they were dead before arriving here? They were fairly well packaged in the factory container and the original little plastic had was still sealed.

Just to confirm, sounds stupid to ask but, semiconductors showing a dead short, it's unequivocally and irrevocably dead, isn't it?

[Bendba]

That's f*ed up alright. I guess they are not producing that one anymore.

Dead short in both direction with both diode meter and ohm meter.
I guess I just have to contact the seller.

[julianhigginson]

And now I just bought a great big motorised desk for my new office, which isn't quite finished yet..

Thanks Halcyon!

[Cubdriver]

That's f*ed up alright. I guess they are not producing that one anymore.

Dead short in both direction with both diode meter and ohm meter.
I guess I just have to contact the seller.

   That's a bummer.  Sorry to hear.

-Pat

[CharlieWorton]

Dead short in both direction with both diode meter and ohm meter.
I guess I just have to contact the seller.

Yeah, that's about a 9.3 on the WreckedEr scale.  My sympathies.  Hopefully the reseller will make good.  From your obvious knowledge of the product, it's difficult to imagine you did anything wrong.  So either they sent you dead units - their fault - or they packaged them improperly, so as to render them susceptible to damage during shipping.  Again, their fault.

Reminds me of my bandsaw purchase.  Spend a chunk of change, think you've got a real solution, and then - oops.  Hope yours is more returnable than my bandsaw was.

On the purchase end of things - an FM radio kit I ordered a couple of months ago showed up.  Think it was around $9 USD from banggood.  Digital display, chrome antenna - what's not to love?

>Charlie

[Bendba]

The seller is sending me some new ones tomorrow, he is going to test them before sending this time.

If you want, I'll send you two dead diodes in exchange for the saw 

That little radio looks like the $15 one at the Chinese shop down town. But you'll probably do a better job at soldering and mounting it

[CharlieWorton]

That little radio looks like the $15 one at the Chinese shop down town. But you'll probably do a better job at soldering and mounting it

Oh, we can hope!  I buy these kits mostly to hone my soldering experience.  But I'm way, way down at the beginner level.  But... I guess we all start there.

Glad the retailer is shipping you two new units.  Hope things work out!

>Charlie

[Towger]

Assembled and tested, for $3.5.

But where is the fun in that.   There are some nice SDR HF transceiver kits available which I would love to build. But they are serious money, just for the base unit. 

[Bendba]

Russian laser diodes follow up:

The seller tested a few of his stock parts and they all measure the same. He then done some researches (in Russian) and it turns out that particular one has a current transformer integrated in the casing.
He sent me a link to a forum in Russian, still trying to work out through the translation.

Has anyone ever heard of that, a current transformer in a diode casing?

[Bendba]

That's why I like those old ancient electronics, they are full of surprise.

I might start a new thread and sacrifice one to an open heart surgery to share some photos of the inside. And if I'm lucky, bypass the transformer.

[djos]

That's why I like those old ancient electronics, they are full of surprise.

I might start a new thread and sacrifice one to an open heart surgery to share some photos of the inside. And if I'm lucky, bypass the transformer.

If you do, can you link to it here please? I'm seriously intrigued. 

[Bendba]

There it is, just click on the quote link.

Hi,

Yesterday, I received two 30W pulsed laser diodes I bought on ebay from Ukraine...

[MosherIV]

I got a Metcal SP200 with 2 tips off ebay 



Sadley, I did not get the original stand, so I will be putting some magnets around the cheap stand they did provide. 

[neo]

i bit the nearly literal bullet and spent $100 (with $50 for shipping) on a nixie tube version of the HP 5340A, with what appears to be every bell and whistle available for it.                                                                                 

I wonder what besides food is edible... (joking)

[slurry]

The beautiful HP 5245L?