Test Equipment Anonymous (TEA) group therapy thread

[Specmaster]

BTW it appears AIM-TTi have opened an outlet ebay store based on the fact that it's all TTi stuff and location is Huntingdon. Some good stuff here:

https://www.ebay.co.uk/usr/testequipmentsales

I hate that! 
I can only see the articles offered when I'm using the ebay.co.uk domain.
If I try to see the list via ebay.de, there is nothing. Nada. Niente.   
Really, I hate it, when ebay (or other platforms) trying to think for me.  *grrrrr*   

Yeah, it works the same way for us in the UK, when you guys post the item number of an item you spot of interest on the .de site, we cannot see it unless we change the .co.uk for .de

[Cerebus]

Well I got thoroughly outbid earlier on this: https://www.ebay.co.uk/itm/233564510066 

Back to debugging C, which I'm actually enjoying for once 

Edit: ... just did this and took 20% of the CPU cycles away from a tight loop . Looks like original author didn't know what XOR was so invented his own.

~m & x | m & ~x  -> x ^ m

Moreover, the compiler doesn't seem to know what XOR is. That kind of strength reduction (e.g. I / 2 => I >> 1) is the cheapest, easiest optimization to implement and you are certain that you aren't changing the semantics of the code (which is not true for all optimizations, some are quite hairy which is why we now have clunky syntax for describing pointers in modern C). You ought to be able to write either expression and get exactly the same machine code.

[GreyWoolfe]

Hmmmmm, it's just odd that one never heard about it till a few years ago and now it's everywhere.

How ever did our grandparents survive?

Most worked harder than we've had too so good sleep was well earnt ! 

Can't say that in my case; growing up on the farm. But damned sure a lot harder than I've worked in the last couple decades, no doubt.

I guess those with sleep apnea were either insomniacs or grumpy bastards all but a day or two a week... 

mnem
 

I have been on CPAP therapy for over 10 years now.  Still a grumpy bastard but at least I sleep well.

[mnementh]

Me too, sometimes.

mnem
C'est la vie!

[mnementh]

      

A quick Heads-Up from the Tool-Dwagon: I just picked up the Dremel 711-01 accessory kit at Wally World for CAD$13 (price in-store; it's still US$23 online); it's got a good assortment of all the stuff you use up and not a lot of the crap you don't.

30 of the cheap 1" cutoff wheels (+1 of the good 1.5" ones), 20 buffing pads with a little tub of rouge, 40 sanding drums, 45 sandpaper discs, 2x each style mandrel, plus 4x grindstones & 1/8" burr, and a Dremel wrench. Good value at that price, tho it looks like they've discontinued the set in favor of one with their damned quick-lock cutoff wheels.

Cheers,

mnem
 

And please, stay well clear of the BNCs with that!

Agreed! Unless, of course, you're using it to cut in the new BNC!

is there anydremel out there ?   don't remind of of the dremel stuff. We got plenty of those rotting away in several dark places ...   No time to use them or government restrictions prohibiting us from doing the stuff we like.   

If you think of the clearly superior Proxxon ones, does it get better that way?

/M, proxxon-owner

+1 for Proxxon 

Nice equipment... tho shipping makes bigger tools like the IBS/E prohibitive to me. I have no complaint with Dremel; I use 2 that are 20 & 25 years old and aside from replacing brushes/bearings, both are still 100% original and work amazingly well. Right now I'm using a 120W Wen because it was CAD$20/NIB on Kijiji when I needed one. I may look into Proxxon again when I go visit the States, or if dad asks what I want for Christmas. 
Their mini belt-sander is a nice-looking detail tool, and the cordless rotary is , but its not BL and with shipping it costs as much as my 6 Kobalt BL drills/impacts/saw put together. Those 40W 60 series are nice minis tho... and even with shipping still quite reasonable, as long as I buy only the motor head and use my own 12V power source.

mnem

[bd139]

Well I got thoroughly outbid earlier on this: https://www.ebay.co.uk/itm/233564510066 

Back to debugging C, which I'm actually enjoying for once 

Edit: ... just did this and took 20% of the CPU cycles away from a tight loop . Looks like original author didn't know what XOR was so invented his own.

~m & x | m & ~x  -> x ^ m

Moreover, the compiler doesn't seem to know what XOR is. That kind of strength reduction (e.g. I / 2 => I >> 1) is the cheapest, easiest optimization to implement and you are certain that you aren't changing the semantics of the code (which is not true for all optimizations, some are quite hairy which is why we now have clunky syntax for describing pointers in modern C). You ought to be able to write either expression and get exactly the same machine code.

Certain optimisation levels in GCC probably do optimise this. They also get progressively more broken. I’m porting to clang soon as well. I haven’t looked at the makefile yet but -g does disable some optimisations. I have had GCC’s dead code elimination toast entire loop bodies (and asserts) before! 

Shifting a bit left and right to multiply or divide by 2 has some foot guns hiding it you’re not careful particularly with portability and overflowing into the sign bit. Best not to wake up in the morning to unexpected buggery

[Cerebus]

Shifting a bit left and right to multiply or divide by 2 has some foot guns hiding it you’re not careful particularly with portability and overflowing into the sign bit. Best not to wake up in the morning to unexpected buggery

Yeah, but this ought to be done in a bit of the compiler that ought to know enough about the target machine not to deploy the foot guns. Strength reduction is just about the safest optimization, if a compiler can't get that right it's probably got bigger problems.

[Brumby]

I have been on CPAP therapy for over 10 years now.  Still a grumpy bastard but at least I sleep well.

That seems completely natural.  You developed a skill to cope with a situation and even though that situation has been addressed, the skill still remains ... to be utilised.   

Me too, sometimes.

Q.E.D.

[beanflying]

Q.E.D.

So what has my surrogate Enabler offered you? 

[mnementh]

That greatest of temptations... A quiet, normal life. 

mnem
Weeth seex joo get egg loll!

[mansaxel]

Yeah, it works the same way for us in the UK, when you guys post the item number of an item you spot of interest on the .de site, we cannot see it unless we change the .co.uk for .de

And basket is per site, while watch list is global, as is account. Whiskey Tango Foxtrot, indeed.

[tonyalbus]

Hi guys,

Review of my new buy... from china... 60Mhz function generator.



Tony

[bd139]

Shifting a bit left and right to multiply or divide by 2 has some foot guns hiding it you’re not careful particularly with portability and overflowing into the sign bit. Best not to wake up in the morning to unexpected buggery

Yeah, but this ought to be done in a bit of the compiler that ought to know enough about the target machine not to deploy the foot guns. Strength reduction is just about the safest optimization, if a compiler can't get that right it's probably got bigger problems.

True. It is GCC here so bigger problems it does have.

I was actually teaching my youngest how to do that in base 10 last week. Her compiler is better than GCC 

[Ero-Shan]

And now you come along with an AC calibrator (much more in need, as I do have some DC calibrators, albeit no top notch ones).

Regarding the Yokogawa YEW 2558 AC calibrator: recently on TIN's ftp-server showed up a lot of manuals etc. from Yokogawa which usually are hard to find:

https://www.eevblog.com/forum/metrology/yokogawa-2558-ac-voltage-standard-service-manual/

Well, thank you again! The unavailability of a manual was a good reason to resist the temptation. Grrr.

But then, you don't even seem to be interested. Wouldn't you like it?

[BU508A]

And now you come along with an AC calibrator (much more in need, as I do have some DC calibrators, albeit no top notch ones).

Regarding the Yokogawa YEW 2558 AC calibrator: recently on TIN's ftp-server showed up a lot of manuals etc. from Yokogawa which usually are hard to find:

https://www.eevblog.com/forum/metrology/yokogawa-2558-ac-voltage-standard-service-manual/

Well, thank you again! The unavailability of a manual was a good reason to resist the temptation. Grrr.

But then, you don't even seem to be interested. Wouldn't you like it?

Believe me, I would. But at the moment I can't buy it. Had to pay 4kEUR for car service and repairs (brakes worn out, motor for the windscreen wipers, leakage of the air-conditioning plus replacing the squeaky fan, new tyres (summer) ...    )
So, if you would give this nice calibrator a tender home, please feel free to do so.

[bd139]

Bugger that reminds me I need to do some work on my car  . Rear tyres / AC recharge and clean it. None of which I want to be bothered with at the moment.

[BU508A]

I know it is a PITA, but when it comes to have a safe car, I do not make any compromises. Not worth it.

Edit:
Any chance, that your eldest want to become a car mechanic? 

[Saskia]

sigh. my car dealer called and wants me to take the car out of winter storage ...
I don't have any space to park it right now.

*sigh*.
maybe I should just sell it ...

[Specmaster]

Yeah, mine needs a wash and the inside valeting but its raining so not today Josephine 

[Specmaster]

@bd139 Thought you might find this of interest, made by one of our members, the member that we were discussing other day with his videos about TEAS.

[bd139]

No TE but new toy. Local linux file / terminal server from a repurposed Lenovo M600 desktop. Currently waiting for a 1TiB M2 SSD to go in it (goes under the heatsink).



No moving parts at all!



Dual core ass end celeron + 4gb RAM.

Would make a reasonable lab machine for Linux / ass end windows stuff. Has built in wifi, 6 USB ports, ethernet, wifi, front/read audio and M2 SSD slot, 1 RAM slot. Runs off a standard Lenovo power brick.

Better than a shitty raspberry poo.

Edit: link if anyone wants one: https://www.ebay.co.uk/itm/114047401423 .... 5 left. come with new power supply, mains cable and antenna. I can't actually see any sign of use. It's new AFAIK.

[bd139]

@bd139 Thought you might find this of interest, made by one of our members, the member that we were discussing other day with his videos about TEAS.

I actually built one of them and sold it 

edit: actually that was the 50W unit I built. 

[Saskia]

off topic stuff deleted ...

[Brumby]

So what has my surrogate Enabler offered you? 

I'll put up photos....

... when the package arrives.


 

[Wolfgang]

@bd139 Thought you might find this of interest, made by one of our members, the member that we were discussing other day with his videos about TEAS.

... am I mistaken or aren't these amps notorious for undersized ferrites that get so hot that they crack apart at full power ?
I am always sceptic if the specific volume power density of an electronic gadget gets above a certain limit ...