What did you buy today? Post your latest purchase!

[technix]

I might have just burned CNY 80 on a piece of hardware I cannot use. I have soldered the pins for breadboarding. But I still need to add the reset button and the JTAG connector so I can saw the KitProg part off. I am going to try skipping the entire PSoC Creator first using my usual Eclipse CDT stack.

[BU508A]

Bought a couple of used AD587LN a while ago from here:

http://www.ebay.com/itm/162254805543

This is what I got (see pictures).
They are clearly soldered out.

[technix]

I might have just burned CNY 80 on a piece of hardware I cannot use. I have soldered the pins for breadboarding. But I still need to add the reset button and the JTAG connector so I can saw the KitProg part off. I am going to try skipping the entire PSoC Creator first using my usual Eclipse CDT stack.

PSoC is a piece of shit without proprietary IDE. You need the IDE and hence Windows.
KitProg connects to main board with not only the 5 pins. There are hidden traces for UART. Breaking off the board you will lose the UART.

I have noticed that and it is damn annoying. I have grabbed an evaluation copy of Windows 10 and thrown it into an instance of VirtualBox.

[Nx-1997]

My first 6.5/7.5 multimeter, an HP 3457A. Seems like it was calibrated in 2012, fairly recent IMO. I would probably remove those seals to check if the battery needs replacing.

[Bendba]

Nice.

I noticed the mains voltage switch is set to 100V. Hope you notice too before plugging it in

[Nx-1997]

Yeah I did notice that but thanks for pointing it out. After owning 5, 5.5 multimeters, I decided to move up the ladder.  Bought this one for 334$ including shipping.

[TheSteve]

The most expensive single component I have ever purchased - a Vishay VHP101 10K 0.005% resistor.

[Cubdriver]

The most expensive single component I have ever purchased - a Vishay VHP101 10K 0.005% resistor.

Wow!  I just looked that up!  73 clams from Digi Key - that's a 'spensive resistomatator!

-Pat

[BU508A]

The most expensive single component I have ever purchased - a Vishay VHP101 10K 0.005% resistor.

If I'm not mistaken, this is a 3458A and not a VHP101 resistor. 

[TheSteve]

Looking at the resistor is boring, it's all about measuring it.

[Bendba]

That's an expensive piece of toaster wire 

...

Just kidding. And there, I'm happy when I find 1 or 0.5% tolerance resistors to scavenge.

[Kjelt]

That is an expensive resistor. Where are you going to use it for ?
Did they supply you with the additional 27 milliohm mounting wire  to make it perfect ?

[CharlieWorton]

Yeah.  Re cutting PCBs with a bandsaw:

You're right.

I think I could have got a cleaner cut if I'd got a rabid beaver high on crystal meth, stuck my finger up his ass and let him gnaw away at the PCB.  Jesus.  Forget about a clean cut; it looked like the results of a fragmentary grenade.

So, I figured I'd return the saw.  But I'd thrown away some of the packaging, so I gave Canadian Tire a quick call to determine if it would be a problem.

"Yeah, I need to return a band saw..."

"Complete, sealed, never been opened?" she cut me off.

"Uhh, well, I did actually open it -"

"Sorry, no returns once the package is opened.  ThankYouForCallingCanadianTireGoodbye!"  Click.

So, that's the return policy at Canadian Tire.  Essentially, they don't have one.

So, I own a bandsaw.

Which acts like a rabid beaver, high on crystal meth.

Sigh.  I have to go wash my finger now.

>Charlie

[DTJ]

Yeah.  Re cutting PCBs with a bandsaw:

......

So, I own a bandsaw.

>Charlie

don't worry you'll find other uses for it - plastic, wood....

[Bendba]

Maybe you can slow it down and retrofit a diamond wire saw instead of the blade. Wouldn't that handle pcb's?

[McBryce]

Yeah.  Re cutting PCBs with a bandsaw:

You're right.

I think I could have got a cleaner cut if I'd got a rabid beaver high on crystal meth, stuck my finger up his ass and let him gnaw away at the PCB.  Jesus.  Forget about a clean cut; it looked like the results of a fragmentary grenade.

So, I figured I'd return the saw.  But I'd thrown away some of the packaging, so I gave Canadian Tire a quick call to determine if it would be a problem.

"Yeah, I need to return a band saw..."

"Complete, sealed, never been opened?" she cut me off.

"Uhh, well, I did actually open it -"

"Sorry, no returns once the package is opened.  ThankYouForCallingCanadianTireGoodbye!"  Click.

So, that's the return policy at Canadian Tire.  Essentially, they don't have one.

So, I own a bandsaw.

Which acts like a rabid beaver, high on crystal meth.

Sigh.  I have to go wash my finger now.

>Charlie

The type of blade you are using will have a major effect on the results. What's the TPI of the blade you're using at the moment? There are carbon blades with up to 24TPI which should give better results. I'd try one of those (after you've washed your finger) before I gave up on the saw completely.

McBryce.

[BU508A]

I think I could have got a cleaner cut if I'd got a rabid beaver high on crystal meth, stuck my finger up his ass and let him gnaw away at the PCB.  Jesus.  Forget about a clean cut; it looked like the results of a fragmentary grenade.

I have this one:
http://www.proxxon.com/en/micromot/27006.php

with the diamond blade NO 28 012

It produces nice and clean cuts. FR4 is not a problem at all and I can really recommend this saw.

Image:


diamond blade:

[djos]

Yeah.  Re cutting PCBs with a bandsaw:

You're right.

I think I could have got a cleaner cut if I'd got a rabid beaver high on crystal meth, stuck my finger up his ass and let him gnaw away at the PCB.  Jesus.  Forget about a clean cut; it looked like the results of a fragmentary grenade.

So, I figured I'd return the saw.  But I'd thrown away some of the packaging, so I gave Canadian Tire a quick call to determine if it would be a problem.

"Yeah, I need to return a band saw..."

"Complete, sealed, never been opened?" she cut me off.

"Uhh, well, I did actually open it -"

"Sorry, no returns once the package is opened.  ThankYouForCallingCanadianTireGoodbye!"  Click.

So, that's the return policy at Canadian Tire.  Essentially, they don't have one.

So, I own a bandsaw.

Which acts like a rabid beaver, high on crystal meth.

Sigh.  I have to go wash my finger now.

>Charlie

  I literally have tears rolling down my cheeks right now, even more after reading it out loud to my wife who is apparently suffering from a sense of humor failure!

Seriously, you made my night! 

[Gyro]

I think I could have got a cleaner cut if I'd got a rabid beaver high on crystal meth, stuck my finger up his ass and let him gnaw away at the PCB.  Jesus.  Forget about a clean cut; it looked like the results of a fragmentary grenade.

I have this one:
http://www.proxxon.com/en/micromot/27006.php

with the diamond blade NO 28 012

It produces nice and clean cuts. FR4 is not a problem at all and I can really recommend this saw.

Image:


diamond blade:

I use one of those cheap tile saws, they already come with a Diamond blade and the water cooling means no dust.

eg. https://www.toolstation.com/shop/p10565?table=no

[GreyWoolfe]

That is a great idea, gyro.  I have cheap Harbor Freight tile saw that I have used for tile cutting.  Never thought to do it with FR4.  The next time I decide to make a circuit board, I will use it.

[macboy]

I think I could have got a cleaner cut if I'd got a rabid beaver high on crystal meth, stuck my finger up his ass and let him gnaw away at the PCB.  Jesus.  Forget about a clean cut; it looked like the results of a fragmentary grenade.

I have this one:
http://www.proxxon.com/en/micromot/27006.php

with the diamond blade NO 28 012

It produces nice and clean cuts. FR4 is not a problem at all and I can really recommend this saw.

Image:
[snip]

diamond blade:
[snip]

I use one of those cheap tile saws, they already come with a Diamond blade and the water cooling means no dust.

eg. https://www.toolstation.com/shop/p10565?table=no

Brilliant!

[JoeN]

The most expensive single component I have ever purchased - a Vishay VHP101 10K 0.005% resistor.

I've purchased one or two FPGAs that come out more expensive that that, but barely.

Does that resistor really have a ZERO TC?  Can you check it over temperature with your VM?  That property is what is being paid for, not the 0.005%.  You can play with pairs of resistors until you find a combination that is 0.005% within 10K without a problem, the issue is that with cheap resistors it will no longer be there once the temperature changes a few degrees.  That TC is the amazing part.

[TheSteve]

The most expensive single component I have ever purchased - a Vishay VHP101 10K 0.005% resistor.

I've purchased one or two FPGAs that come out more expensive that that, but barely.

Does that resistor really have a ZERO TC?  Can you check it over temperature with your VM?  That property is what is being paid for, not the 0.005%.  You can play with pairs of resistors until you find a combination that is 0.005% within 10K without a problem, the issue is that with cheap resistors it will no longer be there once the temperature changes a few degrees.  That TC is the amazing part.

The TC is not really 0 - but it it should be quite low. I believe the resistors are made from different substrates/compounds in series. One increases resistance with temperature, the other decreases with temperature. The idea being they cancel each other out.
I haven't done any extensive testing yet. I need to mount it in a box with low EMF binding posts etc. Then some crude testing can begin.
I have always wanted one, my (terrible) justification was that I was already ordering from Digikey and needed to spend more money to get free overnight shipping. So in my mind I saved 8 bucks on the price of the resistor, lol.

[CharlieWorton]

Hey, DTJ, McBryce - you were right.  Sigh.  Perhaps I will find other uses for the bandsaw.  Or it might just wind up as another tool in my tool museum, right beside my squid stretcher and my female polar bear mounter.   The last might seem a bit odd, but let me tell you: if you ever need to mount a female polar bear, you'd damn well better have the right tool.

Gary M - you know, I keep hearing from everyone that PCBs are so cheap now.  But the cheapest I've found - for a 2.5 X 3.8 inch board with silk screen and solder mask is $61 USD - about $82 CAD + shipping, which will probably bring it up to around $100.  They do 3 boards for that price, but I don't think I need 3 boards.  I just need one board.  So I'm effectively paying $100 for a tiny little board.

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.

Hey, Bendba - one of the joys of this saw is that it takes a 62 inch X 1/4 inch blade, which is a very unusual size.  I did find a listing on Amazon.ca for 5 diamond blades for about $248 CAD with shipping.  But I don't want to gamble that much.  I can also get a 24 tooth blade for about $31 with shipping, which still strikes me as pricey.

Hey, Djos, thanks for the shout out.  Don't worry too much about women not enjoying my humor;  they've never enjoyed it when I've inflicted it on them in person, either.  One young lady even got a court order, prohibiting me from calling her.  The judge looked at her and said, "Is he making threats?"

"No," she replied.  "He's telling jokes."

The judge looked at me.  "Tell me a joke."

"Well," I said, "Two gay judges walk into a bar..."

"I've heard enough.  The order is granted."  Bang went the gavel.

So, you know.  There's a ton of women, and at least one gay judge, that don't like my humor.

Hey, BU508A - I really like the look of that saw.  They don't have a sales rep in Canada; the nearest one is North Carolina, which is roughly 4,000 miles away.  I did a search on Amazon, and couldn't find anything similar; same with lee valley tools.  I'll keep looking.

Hey, Gyro - I think this one, available locally (from a store with an actual return policy) might be similar to what you're using:

https://www.princessauto.com/en/detail/7-in-portable-wet-cutting-tile-saw-with-3-bonus-blades/A-p8237489e

It's even on sale.  $70 CAD, with 3 diamond blades.

The one question I have - how do you keep the work space dry?  Or do you not use the water at all?

Thanks everyone, for all your great comments and suggestions.  I really appreciate it.

Best, Charlie

[tautech]

Charlie
How wide is the blade slot in the table insert ?
For minimising underside breakout you want the slot in the insert to be as narrow as possible....maybe make a better one up out of some ply or acrylic sheet ?