Author Topic: Test Equipment Anonymous (TEA) group therapy thread  (Read 3000629 times)

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Offline nixiefreqq

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #54700 on: April 05, 2020, 06:31:09 pm »
Pleased you didn't try and defend the ugly pig that it is :-DD

geeeeeze.  that is pretty harsh.

am tempted to buy it now.  gotta' root for the underdog.

If you're going to buy it, please take a picture from it next to a TI calculator.
The calculator will look much better, then.  :-DD

dodged a bullet on the fugly fluke 37.

offered $20 on his "$35 buy it now or best offer".

he countered at $32.  so there will be no pictures.




nice try bean, ya' almost sucked me into that one.
post lockdown free range primate
 
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Online bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #54701 on: April 05, 2020, 06:43:18 pm »
If north weald and Southend are shut the diddy donut industry is fucked  :-DD

Essex police are complete knob ends. Have had a few run ins over the years.  :-DD
Hmm, London ones are not much better if at all, didn't you say the other day that they stopped a young boy from shopping and him home again?  |O :-DD

Southend donuts are well fucked according to Essex Live reports, the entire seafront is shut for business of any kind and almost 1 in 10 shops had a fresh made donut machine in it churning out piping hot sugar coated donuts  :-DD

The police here have chilled out now and have been reminded what the act contains and what they can and can't do. Basically they can do not a lot :)

Yeah Southend seafront is going to be completely dead. It was bad enough everywhere when they closed McDonalds - that's when it started going downhill. Where the hell are all the Essex-folk wearing a metalic blue Saxo which sounds like a nazi tank going to go?  Also what about Clacton? What are the police going to do now there's no violence inducing two for one deals on sourz and no slags pulling each other's weaves out outside :-DD

It has gone to shit here. Basically the entire area is Polish folk sitting on benches drinking Famous Grouse with one earphone in being shouted at by a Polish woman. Oh and curtain twitchers. Next time I see someone pointing at me when I go for a walk they're getting full moon.  :-DD

North Weald is real loss for me at the moment as lots of military helicopters used in the construction of Nightingale Hospital and the relief work generally are dropping in there for refuelling  :palm:

All planned air shows for 2020 are already cancelled for the year.

Yeah I was intending to go to Fairford this year and hopefully not get pissed upon quite as much. So much for that  :(

Also nearly booked Nighwish tickets for december but alas that's going to go to shit.

From 2015 which I missed

 
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Offline mansaxel

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #54702 on: April 05, 2020, 06:49:34 pm »
Madness. Dortmund to host 50000 people Ramadan indoor event.  :palm: :scared:

I see it as science winning over superstition.  :-DD

Then again, there are reasonably good empiric data that caring for your neighbour drives the world forward in a beneficial direction, so I think it oughta be stopped.

Online Saskia

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #54703 on: April 05, 2020, 06:58:16 pm »
I will declare them a sacrifice to Freya.
 
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Online xrunner

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #54704 on: April 05, 2020, 07:05:55 pm »
The Queen is talking to us on TV right now!
I am a Test Equipment Addict (TEA) - by virtue of this forum signature, I have now faced my addiction
 

Online bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #54705 on: April 05, 2020, 07:12:26 pm »
I wouldn't listen to that old pedophile hoarding bag of farts  :-DD

(I'm not a royalist if you didn't get that from the above  :-DD)
 

Online Saskia

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #54706 on: April 05, 2020, 07:14:48 pm »
 
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Online xrunner

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #54707 on: April 05, 2020, 07:15:48 pm »
I wouldn't listen to that old pedophile hoarding bag of farts  :-DD

(I'm not a royalist if you didn't get that from the above  :-DD)

I'll translate it for anyone who missed -

She basically said "Chill out y'all - everythang gonna be alright"
I am a Test Equipment Addict (TEA) - by virtue of this forum signature, I have now faced my addiction
 
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Online bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #54708 on: April 05, 2020, 07:20:21 pm »
@bd139 https://youtu.be/r3FEhHF_fzM

That's quite apt actually. Had to use YT auto translate but got the gist of it.
 

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #54709 on: April 05, 2020, 07:20:53 pm »
I wouldn't listen to that old pedophile hoarding bag of farts  :-DD

(I'm not a royalist if you didn't get that from the above  :-DD)
Don't hold back, say what you really mean  :-DD :-DD
Who let Murphy in?

Brymen-Fluke-Solartron-HP-Thurlby-Heathkit-Thander-Tek-Extech-Black Star-GW-Advance-Avo
 

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #54710 on: April 05, 2020, 07:24:36 pm »
There's one for sure about all of this and that is, once its all over and done with, we'll never take for granted things like freedom and, going out, shopping, TP and a host of other things that we will never take for granted ever again.
Who let Murphy in?

Brymen-Fluke-Solartron-HP-Thurlby-Heathkit-Thander-Tek-Extech-Black Star-GW-Advance-Avo
 

Online Saskia

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #54711 on: April 05, 2020, 07:25:51 pm »
and Soros sponsored Fridays for Future will most likely be history.
 

Online bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #54712 on: April 05, 2020, 07:29:53 pm »
I wouldn't listen to that old pedophile hoarding bag of farts  :-DD

(I'm not a royalist if you didn't get that from the above  :-DD)
Don't hold back, say what you really mean  :-DD :-DD

I haven't even started yet  :-DD.

There's one for sure about all of this and that is, once its all over and done with, we'll never take for granted things like freedom and, going out, shopping, TP and a host of other things that we will never take for granted ever again.

Assuming those privileges return afterwards. I can't really trust our government after the last decade or so of manipulation not to try and leverage this as hard as it can.
 
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Offline med6753

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #54713 on: April 05, 2020, 07:30:15 pm »
I wouldn't listen to that old pedophile hoarding bag of farts  :-DD

(I'm not a royalist if you didn't get that from the above  :-DD)

I'll translate it for anyone who missed -

She basically said "Chill out y'all - everythang gonna be alright" (Attachment Link)

No "stiff upper lip" or any of the stereotypical British speak? The Royals are slipping.  :-DD
An old gray beard with an attitude.
 

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #54714 on: April 05, 2020, 07:37:50 pm »
I've been spending time beefing up my bench. I just finished machining an insert for a very basic but useful magnifying lamp. Engine flywheels work surprisingly well as lamp bases :D. Pretty successful weekend project.
Better than a truck rim !  :-DD

Tidy old lathe.  :) A Myford ?

I guess the magnetic holders could be handy on the bench.  ;) Or not !  :scared:
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Online Saskia

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #54715 on: April 05, 2020, 07:39:06 pm »
if the British wish to return to their glory they must remember the old ways. They must invade France.  :-DD
« Last Edit: April 05, 2020, 07:43:35 pm by Saskia »
 

Online bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #54716 on: April 05, 2020, 07:44:08 pm »
Why do you think we built a tunnel  :-DD
 

Online Specmaster

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #54717 on: April 05, 2020, 07:54:23 pm »
Why do you think we built a tunnel  :-DD
Its a trojan horse, they'll never expect us to come from there, they'll be waiting at the channel ports, and then we'll just drive them in to the sea, Blackadder  :-DD :-DD
Who let Murphy in?

Brymen-Fluke-Solartron-HP-Thurlby-Heathkit-Thander-Tek-Extech-Black Star-GW-Advance-Avo
 
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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #54718 on: April 05, 2020, 08:42:01 pm »
Hahaha  :-DD

So I just spent an hour on ebay. Nothing of interest still :--
 

Online tggzzz

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #54719 on: April 05, 2020, 08:44:36 pm »
OK, new toy time, one that I've been waiting to find...

So inevitably I have far too many boxes that draw graphs of voltage-vs-time (scopes), too many that draw voltage-vs-frequency (spetrum analysers), but until today nothing that would complete the triumvirate by drawing frequency-vs-time (a modulation domain analyser MDA). I did buy an MDA cheaply last year, but it was effin heavy, junk and ended up in the skip – after I rescued an HP80811-60111 OCXO.

So I've been keeping an eye out for an MDA, but mostly they are £600+P&P (on my limit for a toy), often have dents, and even if a display is shown, the self-check screen shows a fault. Not interested.

So, when I noticed an Agilent 53310A where the owner showed it measuring things and also a clean self-test screen, I looked more closely. Since it had the high stability oscillator and third RF channel and was only £250+P&P, I jumped at the chance, even though that mutated into £350 and would take 4 weeks to get here. In the event, it arrived in 2 weeks :)

I remembered to change both mains voltage settings, and pulled off the lid, and the tube was still intact, so I turned it on, and bingo: I'm a happy camper.



So, what can you do with it? Obviously look at modulated signals up to 200MHz (ch A) or 2.5GHz (ch C), e.g. FM/PSK, or VCO transients as they change frequency. But, since it is fancifully and accurately described as a frequency microscope you can do much more interesting things than that.

The first task was to look at the output of my OCXO as it turned on and warmed up. The display isn't wonderful, but the top thin band shows a "panorama" of the entire f-vs-t graph captured over 800s, and the lower main section is a narrow window of that display.

The first thing to note is the number of digits in the frequency display, and that the vertical frequency scale is +-200Hz. The OCXO starts off 200Hz (20ppm) low, but after 400s it looks pretty close to nominal, but how close?




Or the same information presented as a histogram, vertical scale is logarithmic.



Looking at the histogram of the stable oscillator shows that (relative to the MDA's internal oscillator) it is 621mHz (62ppb low), with an RMS noise of 216mHz. Frequency microscope indeed :)



But, arguably more interestingly, even with a 200MHz input, it can measure sub-nanosecond risetimes, roughly equivalent to a 1GHz or faster scope.

The technique is to measure connect both channels A and B to the same input, channel A with a threshold at 10%, channel B at 90%, and measure the time difference between the two inputs with a resolution of 70ps.

I've previously measured my 74lvc1g14 step generator as having a risetime of ~250ps. The MDA indicates 370ps (and 200ps for 20%-80%). That's close since it is pushing the limits of the instrument; I need to sit down and fully understood the specification graphs in the manual.




And I'm sure it can do more strange and wonderful things :)
« Last Edit: April 05, 2020, 08:52:44 pm by tggzzz »
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Online mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #54720 on: April 05, 2020, 08:46:17 pm »
Pleased you didn't try and defend the ugly pig that it is :-DD
geeeeeze.  that is pretty harsh. am tempted to buy it now.  gotta' root for the underdog.
If you're going to buy it, please take a picture from it next to a TI calculator. The calculator will look much better, then.  :-DD
dodged a bullet on the fugly fluke 37. offered $20 on his "$35 buy it now or best offer". he countered at $32.  so there will be no pictures. nice try bean, ya' almost sucked me into that one.

I just offered him $15.  >:D

mnem
*currently enjoyng the illusion known as lunchtime*
 
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Online bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #54721 on: April 05, 2020, 08:50:20 pm »
OK, new toy time, one that I've been waiting to find...

So inevitably I have far too many boxes that draw graphs of voltage-vs-time (scopes), too many that draw voltage-vs-frequency (spetrum analysers), but until today nothing that would complete the triumvirate by drawing frequency-vs-time (a modulation domain analyser MDA). I did buy an MDA cheaply last year, but it was effin heavy, junk and ended up in the skip – after I rescued an HP80811-60111 OCXO.

So I've been keeping an eye out for an MDA, but mostly they are £600+P&P (on my limit for a toy), often have dents, and even if a display is shown, the self-check screen shows a fault. Not interested.

So, when I noticed an Agilent 53310A where the owner showed it measuring things and also a clean self-test screen, I looked more closely. Since it had the high stability oscillator and third RF channel and was only £250+P&P, I jumped at the chance, even though that mutated into £350 and would take 4 weeks to get here. In the event, it arrived in 2 weeks :)

I remembered to change both mains voltage settings, and pulled off the lid, and the tube was still intact, so I turned it on, and bingo: I'm a happy camper.



So, what can you do with it? Obviously look at modulated signals up to 200MHz (ch A) or 2.5GHz (ch C), e.g. FM/PSK, or VCO transients as they change frequency. But, since it is fancifully and accurately described as a frequency microscope you can do much more interesting things than that.

The first task was to look at the output of my OCXO as it turned on and warmed up. The display isn't wonderful, but the top thin band shows a "panorama" of the entire f-vs-t graph captured over 800s, and the lower main section is a narrow window of that display.

The first thing to note is the number of digits in the frequency display, and that the vertical frequency scale is +-200Hz. The OCXO starts off 200Hz (20ppm) low, but after 400s it looks pretty close to nominal, but how close?



Looking at the histogram of the stable oscillator shows that (relative to the MDA's internal oscillator) it is 621mHz (62ppb low), with an RMS noise of 216mHz. Frequency microscope indeed :)



But, arguably more interestingly, even with a 200MHz input, it can measure sub-nanosecond risetimes, roughly equivalent to a 1GHz or faster scope.

The technique is to measure connect both channels A and B to the same input, channel A with a threshold at 10%, channel B at 90%, and measure the time difference between the two inputs with a resolution of 70ps.

I've previously measured my 74lvc1g14 step generator as having a risetime of ~250ps. The MDA indicates 350ps (and 200ps for 20%-80%). That's close since it is pushing the limits of the instrument; I need to sit down and fully understood the specification graphs in the manual.



And I'm sure it can do more strange and wonderful things :)

Ahha. I had a personal bet with myself that it was an MDA you suggested the other day. Nice score that and for a reasonable price as well  :-+

Don't you have to be rather careful with coax lengths with that sort of resolution?
 

Online mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #54722 on: April 05, 2020, 08:54:57 pm »
OK, new toy time, one that I've been waiting to find...

(SNIP for sanity's sake)

And I'm sure it can do more strange and wonderful things :)
Jeezus man... you better go out on the porch and have you a smoke after a shagg like that. :-DD

mnem


 

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #54723 on: April 05, 2020, 08:59:01 pm »
Ahha. I had a personal bet with myself that it was an MDA you suggested the other day. Nice score that and for a reasonable price as well  :-+

Don't you have to be rather careful with coax lengths with that sort of resolution?

You know me too well :)

Connecting the A input to the B input is done internally, so nominally it ought to be calibrated out. However, with unfortunate choices of threshold and hysteresis you can find the transition time is either 400ns (not ps!) or even negative. Erm; the measurement is a bit fragile unless a lot of care is taken. And then there are the error limits to understand.
There are lies, damned lies, statistics - and ADC/DAC specs.
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Having fun doing more, with less
 
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Online bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #54724 on: April 05, 2020, 09:02:31 pm »
Sounds like a set of interesting problems to be absorbed in at the moment.

I’m looking at land rovers. Never good that  :-DD
 


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