Test Equipment Anonymous (TEA) group therapy thread

[WastelandTek]

^ impressive exercise

but...Leo Bodnar man

[Kosmic]

^ impressive exercise

but...Leo Bodnar man

Yeah I know, but I don't need a calibrated 40ps pulse generator. Besides, making it is 90% of the fun 

[WastelandTek]

right on

[0culus]

Found couples of 2N2369 laying around and decided to improvise quickly a Jim Williams pulse generator on the breadboard (yes breadboard  ) And it's not that bad!



The Owon XDS3202E is doing a good job and reporting 1.2ns (rated 1.7ns) while probing with it's 200Mhz 10x probe.



The Lecroy DDA-260 is reporting 965ps while probing with a AP020 1Ghz active probe.



Next step is to try with better connector and enclosure.

Here's a neat hack to try: the 2N2369 case is connected internally to the collector (check with a continuity tester, I might be backwards) so you can reduce the inductance of the whole setup by completely snipping off that lead and using the case to make a solder connection. I did one Manhattan style this way and it dramatically improved the performance, with far less ringing.

[mnementh]

Ambassador Kosh: “Understanding is a three-edged sword: your side, their side, and the truth.”

Dr. Jones: "If it's truth you're interested in, Dr. Tyree's Philosophy class is right down the hall."

...Anyone here made up any USB A to USB mini B cables at all?  I'm making some up as for some reason I seem to have lost some that came with equipment. I know how to wire the A plug as I have already made some A to micro leads OK. I know refer to the internet and google for it, right? But here's the problem, do so and you'll be confused because there is 2 conflicting wiring diagrams, 1 is correct and the other is the mirror image   

Mirror image is caused by dumbasses who don't know which connector (plug or socket) the pinout order is for and fuck it up.

The actual pinout is the same - Mini or Micro. Confirm by plugging the cable into the device and checking that GND is in the correct place on the other end by finding continuity with the shield hood. If it powers up but doesn't work (sometimes it'll make "the USB IN ding" just to fuck with your head), you have D+ & D- reversed.

mnem
 

[mnementh]

And Now for Something Completely...

I am currently polluting my son's mind with Monty Python and the Holy Grail. This is his first Monty; a Rite of Passage.

mnem
*snif* They grow up so fast...

So you are wisely saving the FF Nudity and Biggus Dickus for next week  

vale Terry Jones 

"Seize him! Seize him! Blow your noses and seize him!!!"

mnem
*sniggering off to gladiator school*

[mnementh]

...Found couples of 2N2369 laying around and decided to improvise quickly a Jim Williams pulse generator on the breadboard (yes breadboard  ) And it's not that bad!      Next step is to try with better connector and enclosure.

Here's a neat hack to try: the 2N2369 case is connected internally to the collector (check with a continuity tester, I might be backwards) so you can reduce the inductance of the whole setup by completely snipping off that lead and using the case to make a solder connection. I did one Manhattan style this way and it dramatically improved the performance, with far less ringing.

With SMDs you could build it dead-bug to the case and make all the leads micro-short. Also small enough to integrate into a BNC or hide in a tooth, 60s Russian-spy style. 

Would be nice if Free Electron were to release the files or let someone else produce his keychain JWPulser...   

mnem

[AVGresponding]

Oh well, the 34401A finally went for £191, which is probably insane for a broken meter.

Yeah that's the one I was looking at when I posted asking about unobtainium levels on display parts.

When it went past £50 I was out lol, I figured there's a fair chance the guy got it back broken because the person he sold it to swapped the good parts for bad ones and returned it DOA...

[beanflying]

I failed Square Pegs into round holes in Kindergarten so I will stick with Round Pegs into Round Holes for my second third childhood. Still need to come down another touch as it measures 19.92-19.98 and grabs in some of the holes. Original measured 20.1'ish for a 20mm design.

Might not be a precision issue as much as a curve to polygon thing 

Or maybe a bigger Hammer maybe

[Martin.M]

have ordered seeds: Trinidad Moruga Scorpion

the flowerpot is need for calibrating Scovilles

[bd139]

Good luck with both growing and eating that here in Europe. I manage to grow about 5 chillis a year here. Don’t know why I bother. 

Edit: actually this current electronics resurgence in my life is owed to chillis as I spent some time designing an analogue sequencer that would periodically blow the seedlings around with a couple of PC fans to strengthen them. It escalated from there 

[Wolfgang]

... (for a small fortune, of course) 

you blame him?

No. It took this guy YEARS of hard work to get everything going. 

[Wolfgang]

Found couples of 2N2369 laying around and decided to improvise quickly a Jim Williams pulse generator on the breadboard (yes breadboard  ) And it's not that bad!



The Owon XDS3202E is doing a good job and reporting 1.2ns (rated 1.7ns) while probing with it's 200Mhz 10x probe.



The Lecroy DDA-260 is reporting 965ps while probing with a AP020 1Ghz active probe.



Next step is to try with better connector and enclosure.

Here's a neat hack to try: the 2N2369 case is connected internally to the collector (check with a continuity tester, I might be backwards) so you can reduce the inductance of the whole setup by completely snipping off that lead and using the case to make a solder connection. I did one Manhattan style this way and it dramatically improved the performance, with far less ringing.

For the freaks: The (unabtainium) 2N2501 gold dopen switching parts are still a tick faster (if brutally soldered to the output connector in Bronx building style or on a PCB).

electronicprojectsforfun.wordpress.com/pulse-generators/avalanche-transistor-pulsers/

Using larger transistors can create pulses that can be used to test ESD immunity or the robustness of scope front ends DONT TRY THIS AT HOME. 

[tggzzz]

And Now for Something Completely...

I am currently polluting my son's mind with Monty Python and the Holy Grail. This is his first Monty; a Rite of Passage.

"The Life of Brian" was deemed so mind-polluting that quite a few local councils banned it from their cinemas. Example: Aberystwyth banned it for 30 years until 2009.
http://news.bbc.co.uk/1/hi/wales/mid/7514423.stm

[bd139]

Great film. Especially the continuity bit with the space ship.

Ok so really dumb question here. I’m sizing up a new transformer for the PM3217. Looks like a small 24V toroidal job will suit fine. However sizing the thing is a problem as I usually just overestimate considerably for such tasks but I can’t here because of space constraints.

So the question is: how do I size a transformer in VA minimally from watts or current delivered into the filter capacitor? 

Edit: appear to have answered my own question with TAoE 9.5.2. Must RTFB first! 

[tggzzz]

Found couples of 2N2369 laying around and decided to improvise quickly a Jim Williams pulse generator on the breadboard (yes breadboard  ) And it's not that bad!



The Owon XDS3202E is doing a good job and reporting 1.2ns (rated 1.7ns) while probing with it's 200Mhz 10x probe.



The Lecroy DDA-260 is reporting 965ps while probing with a AP020 1Ghz active probe.



Next step is to try with better connector and enclosure.

Fun, but because you don't know the peak amplitude and waveform, it doesn't tell you very much about the risetime. For that you need a step.

[mansaxel]

Friday, I'm getting switched over to the fastest internet service offered by Virgin, 516MBs, anyone already on it? If so is it as good as they say or do you not get the speeds they claim? I currently have the 200 service, 221Mbs download and 21Mbs upload.

516 MiB? Some upgrade from 27/2 :-) I've got 100/100. Megabits, that is. Can get 1000/1000, and the BiDi fibre transceiver does link up in that speed,  so the limit is just in software. Price was not right then, though, but a switchover might enable this.

[bd139]

Honestly what do you do with all that bandwidth?  I'm quite happy here on 63/16. I can crank that to 270/35 but I don't need it.

[BU508A]

That’s sooooo annoying seeing that as I need a ZM1000 tube 

I think a Czech guy called Dalibor Farny still makes them (for a small fortune, of course) 

Dalibor makes the RZ568M which is size-like the Z568M (one of the biggest nixie tubes I'm knowing of)
The ZM1000 is much smaller. 14mm height (symbol, ZM1000) vs. 50mm height (symbol, Z568M)

http://www.tube-tester.com/sites/nixie/data/z568m.htm
http://www.tube-tester.com/sites/nixie/data/zm1000-philips.htm

[Specmaster]

And Now for Something Completely...

I am currently polluting my son's mind with Monty Python and the Holy Grail. This is his first Monty; a Rite of Passage.

mnem
*snif* They grow up so fast...

Poor kid, he'll be having nightmares now full of exploding sheep and a big foot squashing things.

[BU508A]

Found couples of 2N2369 laying around and decided to improvise quickly a Jim Williams pulse generator on the breadboard (yes breadboard  ) And it's not that bad!



The Owon XDS3202E is doing a good job and reporting 1.2ns (rated 1.7ns) while probing with it's 200Mhz 10x probe.



The Lecroy DDA-260 is reporting 965ps while probing with a AP020 1Ghz active probe.



Next step is to try with better connector and enclosure.

Fun, but because you don't know the peak amplitude and waveform, it doesn't tell you very much about the risetime. For that you need a step.

This is my Jim-Williams fast-pulse generator vs. the Leo Bodnar one:

Jim-Williams:


Leo Bodnar:


The transistor (this is a prototype, I've used a socket, because I'd like to test several transistors):


The BNC connector:


The power supply which generates the +120V


Edit: fixed wrong picture

[med6753]

Honestly what do you do with all that bandwidth?  I'm quite happy here on 63/16. I can crank that to 270/35 but I don't need it.

Ditto. I pay for 60/25 but typically get 80 down and it's more than enough.
 

[mansaxel]

Honestly what do you do with all that bandwidth?  I'm quite happy here on 63/16. I can crank that to 270/35 but I don't need it.

I've got servers at home supplying storage for servers in the cloud.

And, my backup is in another country.

Also,  TCP works much better with symmetrical bandwidth.

My children are good at consuming videos online...

And, I can. 

[Specmaster]

Honestly what do you do with all that bandwidth?  I'm quite happy here on 63/16. I can crank that to 270/35 but I don't need it.

Haha, this house is known as the Techno House, this is my equivalent to the 8.5 digit meter I suppose, don't really need it, but why the hell not, especially when they are effectively giving it to me because of being a long and loyal customer 

We have 3 games consuls which are connected for long periods, playing interactive online games with friends and other family members in the area, 3 desktop PC's streaming video, downloading large files, Internet radios, 4 mobile phones, 5 tablets that could also be connected to the web, 2 smart TV's and many other bits and bobs all connecting to the web.

I do loads of downloads of books etc, many never get read from cover to cover because they are technical reference books and the like and I like to be a speed demon when it comes to downloading, it's the only kind of speeding that is possible days that isn't frowned upon 

Besides when they chuck into the mix, the complete TV package, sport and films included a SIM for my phone on a monthly payment plan with unlimited data for the monthly plan cost of £0, and the total price per month is slightly less than I currently pay, it seems rude not to really 

[med6753]

Since my ISP is a cable TV company they keep trying to get me to sign up for free 200 down if I get the 3 way package of TV, phone, internet for $99 plus tax for one year. After the one year watch out and take out a mortgage.

I dumped their TV service a year ago because of their ridiculous prices. I don't want nor need a house phone. So they can stick it.