Test Equipment Anonymous (TEA) group therapy thread

[bd139]

That's the slightly larger ones I think from the Far East.

Oh and my IRF510 "made with whatever was lying around" RF amps  .

I love the smell of burning ferrite in the morning 

Edit: mostly looking at AF stuff now rather than RF. On the bucket list is a JLH amplifier which I never got around to building.

[sb42]

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! 

https://godbolt.org/z/f7YURZ

So you must be on a version older than gcc-4.7.1, or compiling without -O? If the latter, it doesn't look like clang will do any better.

[Mr. Scram]

Anyone have any experience with good RS232>USB cables?

https://www.eevblog.com/forum/reviews/wtb-good-rs-232-to-usb-cables/msg3042690/

[Cerebus]

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 ...

That may have some missing background for some folks. It's not uncommon for Germans to have two cars, a winter car and a summer car. You store one and drive the other and the government will let you bounce your car tax between the two. It's by no means universal but is more commonly done in the parts of Germany where summer and winter driving conditions are significantly different. The law surrounding it might vary from state to state, one of the Germans will have to fill that in, but I know you can do it in Hesse and I think I know someone who does it in NRW.

[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! 

https://godbolt.org/z/f7YURZ

So you must be on a version older than gcc-4.7.1, or compiling without -O? If the latter, it doesn't look like clang will do any better.

Interesting. That's a shit load easier than arguing with objdump 

It must be without -O then. I will decipher the makefile. Thanks for the heads up 

Edit: compiler ID is "gcc version 4.8.5 20150623 (Red Hat 4.8.5-39) (GCC)"

Edit 2: fucks sake - theres something which frigs -O off if someone sets -g. AAAaaaagh fuck this pile of shit.

Edit 3: next step, rewrite the damn makefile and move clang in. At least it's not bloody autoconf crap.

[BU508A]

Anyone have any experience with good RS232>USB cables?

https://www.eevblog.com/forum/reviews/wtb-good-rs-232-to-usb-cables/msg3042690/

I'm using since years a RS232 <--> USB cable with the FTDI chip and never had any issues.

Example:
https://www.ebay.com/itm/163872410829

Mine is looking very similiar.

[Cerebus]

Another purchasing heads up: this time wire strippers and on eBay.



The listing is for the Size 1 Range 0.12-0.4mm, the photo is of the Size 2 Range 0.25-0.80mm (30-20 AWG). I bought one and got the 0.25-0.80mm size as illustrated. (I didn't care which size I got so took a punt). The standard price for these is £47 inc VAT and these are being punted out for £15. Anyone who has used these will tell you they are nice precise strippers, worth paying for at full price, a bargain at £15.

Listing here: https://www.ebay.co.uk/itm/C-k-Wire-Stripper-Size-1-Range-0-12-0-4mm/333552795843, posts to most places.

[BU508A]

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 ...

That may have some missing background for some folks. It's not uncommon for Germans to have two cars, a winter car and a summer car. You store one and drive the other and the government will let you bounce your car tax between the two. It's by no means universal but is more commonly done in the parts of Germany where summer and winter driving conditions are significantly different. The law surrounding it might vary from state to state, one of the Germans will have to fill that in, but I know you can do it in Hesse and I think I know someone who does it in NRW.

That is called a "Saisonkennzeichen" (seasonal plate). German Wikipedia knows it exactly:
https://de.wikipedia.org/wiki/Kfz-Kennzeichen_(Deutschland)#Saisonkennzeichen

[Mr. Scram]

Another purchasing heads up: this time wire strippers and on eBay.

The listing is for the Size 1 Range 0.12-0.4mm, the photo is of the Size 2 Range 0.25-0.80mm (30-20 AWG). I bought one and got the 0.25-0.80mm size as illustrated. (I didn't care which size I got so took a punt). The standard price for these is £47 inc VAT and these are being punted out for £15. Anyone who has used these will tell you they are nice precise strippers, worth paying for at full price, a bargain at £15.

Listing here: https://www.ebay.co.uk/itm/C-k-Wire-Stripper-Size-1-Range-0-12-0-4mm/333552795843, posts to most places.

I have to admit I don't have a clue how those are supposed to work. Youtube doesn't seem to know either.

[bsudbrink]

Another purchasing heads up: this time wire strippers and on eBay.

(Attachment Link)

The listing is for the Size 1 Range 0.12-0.4mm, the photo is of the Size 2 Range 0.25-0.80mm (30-20 AWG). I bought one and got the 0.25-0.80mm size as illustrated. (I didn't care which size I got so took a punt). The standard price for these is £47 inc VAT and these are being punted out for £15. Anyone who has used these will tell you they are nice precise strippers, worth paying for at full price, a bargain at £15.

Listing here: https://www.ebay.co.uk/itm/C-k-Wire-Stripper-Size-1-Range-0-12-0-4mm/333552795843, posts to most places.

I have a couple of these.  The problem I've found is that the plastic goes brittle with age and cracks.  Maybe newer ones have better/different plastics but that photo looks just like mine.

[bsudbrink]

Another purchasing heads up: this time wire strippers and on eBay.

The listing is for the Size 1 Range 0.12-0.4mm, the photo is of the Size 2 Range 0.25-0.80mm (30-20 AWG). I bought one and got the 0.25-0.80mm size as illustrated. (I didn't care which size I got so took a punt). The standard price for these is £47 inc VAT and these are being punted out for £15. Anyone who has used these will tell you they are nice precise strippers, worth paying for at full price, a bargain at £15.

Listing here: https://www.ebay.co.uk/itm/C-k-Wire-Stripper-Size-1-Range-0-12-0-4mm/333552795843, posts to most places.

I have to admit I don't have a clue how those are supposed to work. Youtube doesn't seem to know either.

The black rectangle slides left and right to control the amount of insulation removed.  There is an adjustment that controls how much the stripper can close and consequently how "deep" the blades bite into the insulation.  Think of them like a pair of tweezers.  You insert the wire at the left.

[Ice-Tea]

Another purchasing heads up: this time wire strippers and on eBay.

(Attachment Link)

The listing is for the Size 1 Range 0.12-0.4mm, the photo is of the Size 2 Range 0.25-0.80mm (30-20 AWG). I bought one and got the 0.25-0.80mm size as illustrated. (I didn't care which size I got so took a punt). The standard price for these is £47 inc VAT and these are being punted out for £15. Anyone who has used these will tell you they are nice precise strippers, worth paying for at full price, a bargain at £15.

Listing here: https://www.ebay.co.uk/itm/C-k-Wire-Stripper-Size-1-Range-0-12-0-4mm/333552795843, posts to most places.

Have used those and agree: cool stuff.

[Kosmic]

Anyone have any experience with good RS232>USB cables?

https://www.eevblog.com/forum/reviews/wtb-good-rs-232-to-usb-cables/msg3042690/

I'm using since years a RS232 <--> USB cable with the FTDI chip and never had any issues.

Example:
https://www.ebay.com/itm/163872410829

Mine is looking very similiar.

Same here. I use those cheap blue adapters from ebay and they works fine.

[URI]

Crap!
Followed the call and also ordered a Xtal tester from ebay. Ordered from the seller pretending to be shipping from the UK because of hopefully shorter shipping times.
Only some ours on the next day (today) I received message from the seller stating he would like to cancel my order because he has none left in stock.
This is the ebay offer I bought from after he wrote me, today, 16:30 GMT, I didn't even order last one offered:


I'm pissed.   
OTH perhaps it's better this way, who knows?   

[tonyalbus]

Review of my new TTi TF930



Will post more of my current counters later.... (

Tony

[tonyalbus]

You guys prob. know this stuff...
but i nice view on my collection of counters.

Tony

[Specmaster]

That's the slightly larger ones I think from the Far East.

Oh and my IRF510 "made with whatever was lying around" RF amps  .

I love the smell of burning ferrite in the morning 

Edit: mostly looking at AF stuff now rather than RF. On the bucket list is a JLH amplifier which I never got around to building.

AF eh, good idea, have you got any of those BD139's left? You can get to use one of them as a replacement for one of the original 1969 design because they are all obsolete now.

[Specmaster]

Crap!
Followed the call and also ordered a Xtal tester from ebay. Ordered from the seller pretending to be shipping from the UK because of hopefully shorter shipping times.
Only some ours on the next day (today) I received message from the seller stating he would like to cancel my order because he has none left in stock.
This is the ebay offer I bought from after he wrote me, today, 16:30 GMT, I didn't even order last one offered:


I'm pissed.   
OTH perhaps it's better this way, who knows?   

Yeah, thats the same seller who also cancelled mine. They sell them on BangGood for less money, but they are now I think, only available from their Canada warehouse now.

[Wolfgang]

That's the slightly larger ones I think from the Far East.

Oh and my IRF510 "made with whatever was lying around" RF amps  .

I love the smell of burning ferrite in the morning 

Edit: mostly looking at AF stuff now rather than RF. On the bucket list is a JLH amplifier which I never got around to building.

... as the next step I suggest a 50W RF amp in the size of a matchbox, all with parts no larger than 0603. Free UHF birdies included, and in the smallprint we should write that the user is supposed to be familiar with Freon cooling.  What a breakthru ! 

[bd139]

lol don't give me ideas.

Today's fuck up: forgot to check if it was SATA or NVMe SSD, blindly buying an NVMe one. Nope it's SATA M.2 ffs. Back to amazon. No computer fun until Saturday now

Will reply to other posts later. Need to walk away from computers FAST 

[beanflying]

Anyone have any experience with good RS232>USB cables?

https://www.eevblog.com/forum/reviews/wtb-good-rs-232-to-usb-cables/msg3042690/

Given the former FTDI Clone 'issues' I have avoided them and stuck with the CH340 based ones including on other Micros where I can. Pictures of my current pair here but just generic evilbay swill and they work really well with zero driver issues (self install) https://www.eevblog.com/forum/testgear/help-need-keysight-34461a-dmm-data-logging-to-xl/msg3021254/#msg3021254

[AVGresponding]

Another purchasing heads up: this time wire strippers and on eBay.

(Attachment Link)

The listing is for the Size 1 Range 0.12-0.4mm, the photo is of the Size 2 Range 0.25-0.80mm (30-20 AWG). I bought one and got the 0.25-0.80mm size as illustrated. (I didn't care which size I got so took a punt). The standard price for these is £47 inc VAT and these are being punted out for £15. Anyone who has used these will tell you they are nice precise strippers, worth paying for at full price, a bargain at £15.

Listing here: https://www.ebay.co.uk/itm/C-k-Wire-Stripper-Size-1-Range-0-12-0-4mm/333552795843, posts to most places.

Have used those and agree: cool stuff.

Pfft, good combi pliers suffice for most of the larger stuff, small side cutters for smaller stuff, and Stanley knife for anything with awkward (ie rubber, silicone, some of the more exotic synthetic polymers that like to stretch) insulation.
You just develop a feel for it.
Well, either that or you develop a large pile of cut wire ends and fingertips on the floor, YMMV.


In the twilight zone at work atm, all our sites remain closed despite management attempts to open them. They did open one, and were told in no uncertain terms by quite senior people in the Council to shut it again. Right. Now.

Having somewhat sideways amounts of knowledge and experience, muggins here gets put upon a bit more than most; while many languish at home "on call", on full pay mind you, no furloughs here, I am "volunteered" to help with a backlog of fire alarm and emergency lights testing.
This means they push a Council van on me, courtesy of someone on long isolation due to medical history, and I get to go and test at such salubrious locations as the Forensic Mortuary, elderly people's homes where the level of paranoia is legitimately quite high, and a sports centre being used as a Covid-19 testing centre. Happy Happy Joy Joy!
The silver lining is due to many sites being inaccessible, I'm home by 2pm for the most part.
The Forensic Mortuary is not full, and it seems likely that the 300 place temporary morgue we built at a decommissioned sports centre won't even be used.
The alleged £300k cost will probably be a source of local complaints, but as we say when we add length to the estimate on an armoured cable, it's better to be looking at it, than looking for it.


Those half days leave me geed up in the afternoon, so on Wednesday, when my bags of test hook clips arrived from Shenzen, I decided to have a soldering session and make up a load of test leads.


The thick green ones are silicone rubber 462/0.08, and are a BALL-ACHE to solder, as anyone who's ever had to do it will confirm. The absolute mass of thin strands wicks away both heat, and solder.
As I hadn't done it in a long while, I had to relearn how... (don't pre-tin them just dose them with flux)
Still, they turned out well, close inspection with a magnifier revealed a good joint.

The others were easy enough, the only caveat being with the thin green ones, they are the 6kV wire, and require the Stanley knife for stripping the insulation (yes, my fingertips are intact, thankyou).

My new accidental TTi arrived while I was soldering, a day late, thanks to Useless Punk Shitheads. My first sight upon opening the parcel generated some qualms:

Luckily the wrecking ball hadn't done any damage except to the cardboard. The use of the mains lead as packing material is... resourceful, if somewhat dubious...

But seems to have caused no problems. The vendor has even added some odd knobs to cover the naked shafts, fnar fnar!

The thing is disappointingly light; it's a switcher, and the cardboard boxes it came in are near as heavy as it is.

Time to turn it on and use some new leads to connect it to some meters:


Seems ok, on the face of it. I'll do some noise measurements at the weekend. Thumbnails added so you can zoom in on the 7150. Maybe I do need to put new backlighting in it after all.   

My (not Corona Dope) turned up today, contains xylene, which I remembered is a VOC, so checked the datasheet before using it.
It's called "Ultimeg 2000/372" and is pretty much just nasty, stinky, gets-everywhere black enamel paint.
Started sealing up the backs of the banana plugs I soldered to the 6kV wire, think I'll put some heatshrink over the lot when it's cured as well. Belt and braces, and all that...

My soldering sesh did have one unintended and temporarily worry inducing side effect: I woke in the middle of the night with a stubborn tickly cough, and given where I've been recently...
Anyway, it was just a minor case of "flux lung". I REALLY need to get an extract fan set up.   

[mnementh]

Spent the morning arguing with Windoze & AVRDUde over serial adapters & trying to get a image of the OE firmware in my 3DP; eventually had to break out my USBasp as it appears my board has no BL installed. 

I can't believe we're 20 years into the new millennium and STILL having to eff with shit like this; bludgeoning Windoze into submission because MS still hasn't gotten over its Jihad against open-source serial comms. 

mnem

[URI]

Crap!
Followed the call and also ordered a Xtal tester from ebay. Ordered from the seller pretending to be shipping from the UK because of hopefully shorter shipping times.
Only some ours on the next day (today) I received message from the seller stating he would like to cancel my order because he has none left in stock.
This is the ebay offer I bought from after he wrote me, today, 16:30 GMT, I didn't even order last one offered:


I'm pissed.   
OTH perhaps it's better this way, who knows?   

Yeah, thats the same seller who also cancelled mine. They sell them on BangGood for less money, but they are now I think, only available from their Canada warehouse now.

Interesting that I'm not alone with that.

I'm glad I added two factor authentication to my ebay account -if this should be any kind of fraud to collect data from ebay users..   

[bd139]

That's the slightly larger ones I think from the Far East.

Oh and my IRF510 "made with whatever was lying around" RF amps  .

I love the smell of burning ferrite in the morning 

Edit: mostly looking at AF stuff now rather than RF. On the bucket list is a JLH amplifier which I never got around to building.

AF eh, good idea, have you got any of those BD139's left? You can get to use one of them as a replacement for one of the original 1969 design because they are all obsolete now.

Got a few BD139 and BD140's floating around