Test Equipment Anonymous (TEA) group therapy thread

[Cerebus]

There were some statements about Ubuntu / linux somewhere up thread I felt a need to correct.

The only statement on Ubuntu that is necessary to remember, for it is true, is: "Ubuntu is zulu for 'I can't install Devuan'"

So what is a " devuan " then ?! 

Debian distribution but using classic SysV style inits rather than the ever creeping, trying to replace everything, sys init substitute systemd.

You know something's gone wrong when a program that is supposedly there just to manage start-up and background process continuity takes over DHCP, name resolution, login management, network configuration, interprocess communication buses and so on, and doesn't stop engulfing other things as time passes. A combination of two classic systems errors: "not invented here" and "over time all programs evolve into entire operating systems in themselves" happening in concert.

[Robert763]

I have 2 HP Spectrum analyzer: 8568a, 3562a
They are in mint condition and working well but they are definitely taking too much room in my small space.

So I thinking to get rid of them and maybe buy some  more modern and more compact SA, what would be your advice?
My only concern is that no modern  SA is working under 9khz like the 3562A

It's nothing to do with "modern" SA. Modern ones are exactly like your old HP 8568s... they don't go down to DC.

Your 3562a is not a SA it's a DSA. DSA go down to DC but only go up to 100kHz....
So what you need if a modern SA plus a modern DSA.

Problem is... do DSA still exist today... I can't find any on Keysight's website.... maybe these things don't exist anymore ? People ?
Given the extremely low bandwidth, 100kHz, maybe today the DSA functionalities are merely some feature one can add as an option to a scope...
Maybe you can get one with a computer based user interface ? Just a small USB box for the analog front-end, and the software running on a computer ?

At any rate there is nothing wrong with modern SA,  they are just like the old ones frequency range-wise, no more no less.

That's fighting talk 
Most modern SAs are "Real Time"  FFT designs while older ones are swept superhetrodyne designs. There is a lot of difference.
See https://rfmw.em.keysight.com/wireless/helpfiles/89600b/webhelp/subsystems/concepts/Content/concepts_types_spec_an.htm
While the results look the same, both types can be set to give different or "incorrect" measurements of a signal. This has led to issues with FFTs being used for EMC compliance measurments for example. More up-todate standards give guidance on use of real time analysers. They should be better for EMC measurements but the standards were written around the swept instruments.

Eh ? What fighting talk ?!   I am all about peace and love 

You misread me, I was nowhere talking about the internal design of a modern SA versus old ones.

Concern of the OP was that modern SA didn't go to DC so only stated that well, old ones did not either !
Only his DSA did because well, it's a DSA not a general purpose SA. But his old HP SA does not go to DC neither do modern ones... internal construction was not a topic here 

9kHz is not DC 
Even the OP's 8568A is specified to 100Hz and it's a microwave swept analyser. I don't think the OP ever mentioned DC......

He did not but he did compare modern SA that typically go down to a few kHz, with his DSA which does go to DC. So that implies he expected modern SA to go to DC, so I simply wanted to point out to him that even his old SA did not go to DC, that general purpose SA don't go to DC, that his DSA could do it only because... well it's a DSA not a general purpose SA ! 

It looks like this morning no matter what I say people misread me so I think it must be something wrong with me, so will just turn off the computer and go do something else instead ! 

Concrete for the garage foundation is due to be delivered today 15H30, 6.8m3 of it.  Need to go out buy some beer to thank the few friends who will come to help me spread it evenly every where.

I have the feeling I just started the unwanted discussion 

Actually I own these two instruments to serve two different needs.
The 3562 will be used for low bandwidth /audio purposes  and the 8568A for everything else (instrument repair, radio oscillator debugging ...)

In my case I do mainly audio things and some instrument repair for which I need high bandwidth instruments.

Today the 3562 can probably be easily replaced with some PC+sound card solution or an Audio Precision if you have deep pockets.
I forgot to say that I also have a much smaller Ono Sokki CF-350Z, which goes from DC to 40Kz. It’s definitely not as good as the HP and offer less functionalities but it should be ok.

At the end I'm probably just looking for a modern and compact SA to replace the huge 8568A.
The 8568A has no special or fancy advanced functions but it work just great and it’s supper easy to use and reliable.
I'm just wondering if a Siglent, Rigol or other equivalent would be a valid alternative.


Alex

Hi Alex,
If the high performance of the 8568A is not important to you then a Siglent SA should do you fine. I'm sure @Tautech can advise what is the best "bang for buck" at the moment. Note that some options can be "released" once the warranty has expired. Personally I'd recommend Siglent over Rigol.

[mnementh]

Some idiot used it in a high energy HV circuit which is a no-no and lucky if they are still alive. And no way would I trust that probe now. It's toast. 

Edit....or perhaps that's a burn from a soldering iron. Either way it's no way for that probe.

I think it would be perfect for the HP linear power supply I posted a few days ago.   -->   https://www.ebay.co.uk/itm/194468003842


I'm strangely drawn to the challenge of repairing / restoring that HP 6264B.     It is such a disaster.  The PCB is burned.  The transformer looks like it got a bit warm.

And if you do manage to resurrect it, you can use it to spot-weld battery tabs or charge your forklift! ^* 

mnem
^* slight exaggeration for comedic effect

[mansaxel]

There were some statements about Ubuntu / linux somewhere up thread I felt a need to correct.

The only statement on Ubuntu that is necessary to remember, for it is true, is: "Ubuntu is zulu for 'I can't install Devuan'"

So what is a " devuan " then ?! 

First, there was Linux. And it came in a box that said "Slackware". And it was almost as sensibly packaged as The True Distribution, that out of Berkeley. Its birth, the Boot, was clear and called "rc.local".  Then came the Red Hat. And there was support and there was RPM. And the rich people paid for it, for they were accustomed to paying.  And the rich people wanted the Boot from the Fifth System of The Real Unix. And so the Red Hat made the Fifth System Boot happen. 

The idealistic people saw that the want of the Red Hat was erratic and not according to the GNU. So they made the Debian. And the Debian was slow to update, for it was  greatly concerned with the freedom and righteousness of all.  But Debian had apt and there was Order.  And there was, after some time, also the Fifth System Boot. 

But the Debian was not pretty, for it was  greatly concerned with the freedom and righteousness of all.

Seeing that it was good in its heart, the Shuttleworth took the Debian and made all decisions that in the name of freedom and righteousness of all in Debian had been left to the User, and they took the Gnome and made half-assed config dialogs. They called this glittering bodge-Job Ubuntu. 

The Red Hat, meanwhile, had toiled hard at pleasing the rich men and the rich men had given the Red Hat money and told the Red Hat that they wanted it to be the sole Linux. So the Red Hat took a man in their service, a man that had been beaten by the people for he had written bad software. But Red Hat saw that the man had a strong, if misguided, will.  Armed with the great powers of the men behind the Red Hat, the beaten man, known as The Lennart, set out to unify the world in revenge.

Thus, the systemd was born.

The Shuttleworth, with their shallow philosophy and their desire to please in the moment, saw that the systemd was a glittering idol. And so they took it to them and put it in the Ubuntu. And it came to be so, that all the software suddenly wanted the systemd even if the systemd was not of the Unix Way, for it did a lot of things and it did not do them well.

The greyest of the beards in the Debian saw  that this was not good. But the children and the shallow people who had been brought up on the Ubuntu had come to the Debian and started to want change that was not properly considered. There was a vote, and a great fighting of words. And many words were said that should not have been uttered.  In the end the people who do not understand Unix prevailed, and the greyest of the beards made an exodus into the desert of the Fifth System Boot. 

In the desert there was no graphical boot, but the greyest beards were pure in their hearts and minds, and their knowledge was vast. They took the things in the Debian that were good, and built a purer one, which they called the Devuan. And there is joy.

Or, one can run any of the BSD variants, because they're much, much better than any Linux. 

[mnementh]

mnem
oh no he ditten't!!!

[Saskia]

I still have my 4.4 BSD source license ...

Read the source, Luke ...

[McBryce]

I still have my 4.4 BSD source license ...

Read the source, Luke ...

May the source be with you!

McBryce.

[mnementh]

Fluke 80K-40 High Voltage probe on ebay this morning.      
Don't mind the burned and melted spot on the tip of the probe. It's sold as used. The seller added "In good condition, guarantee working." Probably works fine 

Some idiot used it in a high energy HV circuit which is a no-no and lucky if they are still alive. And no way would I trust that probe now. It's toast. 

Edit....or perhaps that's a burn from a soldering iron. Either way it's no way for that probe.

Looks like a job for 3DP to me.

I bid... ummm... I have 27 cents Canadian, a purple gumband and a pistachio shell in my pocket. 

mnem

And.... I've just been outbid by mnementh! That's 27 cents and a purple gumband more than I was willing to pay.

McBryce.

Should've used Gixen. 

mnem
*agitating-ily*

[Andrew_Debbie]

I'm strangely drawn to the challenge of repairing / restoring that HP 6264B.     It is such a disaster.  The PCB is burned.  The transformer looks like it got a bit warm.

And if you do manage to resurrect it, you can use it to spot-weld battery tabs or charge your forklift! ^* 

mnem
^* slight exaggeration for comedic effect

It looks like it was used to spot-weld forklifts and then left out in the rain.


If I had use for such a beast,  I'd be far better off buying  this one  --->   https://www.ebay.co.uk/itm/HP-6264B-DC-Power-Supply-0-20V-0-20A-/255206465443

It likely needs work but it will cost less in the end.


These things are full of expensive, hard to find components.     I don't need one.  I'm sane enough to avoid the rust bomb.   

[mnementh]

I suppose this is also possible... 

I mean, yeah... but even if all you get is a good 1150VA XFMR for your 24 quid, you're in the black on it; you've got a box to build any damn kind of PSU inside of you feel like. As long as you can local pick-up, I mean. Shipping that would be a huge WOFTAM.

mnem
 

[mnementh]

I still have my 4.4 BSD source license ...   

Read the source, Luke ...

May the source be with you!

McBryce.

mnem
damn... the Force is effing heavy, man.

[PA0PBZ]

It looks like this morning no matter what I say people misread me so I think it must be something wrong with me, so will just turn off the computer and go do something else instead ! 

Turn off the computer?? After 5 pages of explaining that you never turn it off? Yeah, there's something wrong here! 

[psykok]

I have 2 HP Spectrum analyzer: 8568a, 3562a
They are in mint condition and working well but they are definitely taking too much room in my small space.

So I thinking to get rid of them and maybe buy some  more modern and more compact SA, what would be your advice?
My only concern is that no modern  SA is working under 9khz like the 3562A

It's nothing to do with "modern" SA. Modern ones are exactly like your old HP 8568s... they don't go down to DC.

Your 3562a is not a SA it's a DSA. DSA go down to DC but only go up to 100kHz....
So what you need if a modern SA plus a modern DSA.

Problem is... do DSA still exist today... I can't find any on Keysight's website.... maybe these things don't exist anymore ? People ?
Given the extremely low bandwidth, 100kHz, maybe today the DSA functionalities are merely some feature one can add as an option to a scope...
Maybe you can get one with a computer based user interface ? Just a small USB box for the analog front-end, and the software running on a computer ?

At any rate there is nothing wrong with modern SA,  they are just like the old ones frequency range-wise, no more no less.

That's fighting talk 
Most modern SAs are "Real Time"  FFT designs while older ones are swept superhetrodyne designs. There is a lot of difference.
See https://rfmw.em.keysight.com/wireless/helpfiles/89600b/webhelp/subsystems/concepts/Content/concepts_types_spec_an.htm
While the results look the same, both types can be set to give different or "incorrect" measurements of a signal. This has led to issues with FFTs being used for EMC compliance measurments for example. More up-todate standards give guidance on use of real time analysers. They should be better for EMC measurements but the standards were written around the swept instruments.

Eh ? What fighting talk ?!   I am all about peace and love 

You misread me, I was nowhere talking about the internal design of a modern SA versus old ones.

Concern of the OP was that modern SA didn't go to DC so only stated that well, old ones did not either !
Only his DSA did because well, it's a DSA not a general purpose SA. But his old HP SA does not go to DC neither do modern ones... internal construction was not a topic here 

9kHz is not DC 
Even the OP's 8568A is specified to 100Hz and it's a microwave swept analyser. I don't think the OP ever mentioned DC......

He did not but he did compare modern SA that typically go down to a few kHz, with his DSA which does go to DC. So that implies he expected modern SA to go to DC, so I simply wanted to point out to him that even his old SA did not go to DC, that general purpose SA don't go to DC, that his DSA could do it only because... well it's a DSA not a general purpose SA ! 

It looks like this morning no matter what I say people misread me so I think it must be something wrong with me, so will just turn off the computer and go do something else instead ! 

Concrete for the garage foundation is due to be delivered today 15H30, 6.8m3 of it.  Need to go out buy some beer to thank the few friends who will come to help me spread it evenly every where.

I have the feeling I just started the unwanted discussion 

Actually I own these two instruments to serve two different needs.
The 3562 will be used for low bandwidth /audio purposes  and the 8568A for everything else (instrument repair, radio oscillator debugging ...)

In my case I do mainly audio things and some instrument repair for which I need high bandwidth instruments.

Today the 3562 can probably be easily replaced with some PC+sound card solution or an Audio Precision if you have deep pockets.
I forgot to say that I also have a much smaller Ono Sokki CF-350Z, which goes from DC to 40Kz. It’s definitely not as good as the HP and offer less functionalities but it should be ok.

At the end I'm probably just looking for a modern and compact SA to replace the huge 8568A.
The 8568A has no special or fancy advanced functions but it work just great and it’s supper easy to use and reliable.
I'm just wondering if a Siglent, Rigol or other equivalent would be a valid alternative.


Alex

Hi Alex,
If the high performance of the 8568A is not important to you then a Siglent SA should do you fine. I'm sure @Tautech can advise what is the best "bang for buck" at the moment. Note that some options can be "released" once the warranty has expired. Personally I'd recommend Siglent over Rigol.

"high performance of the 8568A" why that ? should I understand that none of the affordable/cheap SA will be able to provide similar functionality /performance?

[Andrew_Debbie]

I mean, yeah... but even if all you get is a good 1150VA XFMR for your 24 quid, you're in the black on it; you've got a box to build any damn kind of PSU inside of you feel like. As long as you can local pick-up,

mnem
 

WA7 post code - Runcorn.   That's about 75 miles each way, mostly on good roads.    I'd have to stop to charge / eat, so the trip would end up taking 1/2 a day.   I'd do it if I had a use for it.


Tempted, but not going.

[Saskia]

got Mail from Mouser that they got my Kria SOM in stock. Now waiting for the accessory kit.
This is what I am tawkin bout:
https://www.xilinx.com/products/som/kria/kv260-vision-starter-kit.html

[Cerebus]

... 50+ lines elided ...
moment. Note that some options can be "released" once the warranty has expired. Personally I'd recommend Siglent over Rigol.

"high performance of the 8568A" why that ? should I understand that none of the affordable/cheap SA will be able to provide similar functionality /performance?

Quoting about sixty lines to make a one line comment? Really?

The whole quote:comment ratio in posts in here has been creeping higher and higher recently. Can I respectfully ask that folks please  trim their quotes a bit to make reading things a bit easier. There's no need to include all the preceeding context, if people need it they can follow the links in the quote headers.

[dl6lr]

Yes that's what I said, I don't want to wait 30 seconds for the light to turn on every time I flick a light switch ! 

Well, your profile may be different, but my Notebook starts within 2s. Putting the finger on the sensor to sign on takes another second, then the OS is ready with all applications where I left it. It is way faster than the monitor to wake up from standbye.
This is Win10, but I doubt it would be very different with a decent Linux distro.

[Cerebus]

I mean, yeah... but even if all you get is a good 1150VA XFMR for your 24 quid, you're in the black on it; you've got a box to build any damn kind of PSU inside of you feel like. As long as you can local pick-up,

mnem
 

WA7 post code - Runcorn.   That's about 75 miles each way, mostly on good roads.    I'd have to stop to charge / eat, so the trip would end up taking 1/2 a day.   I'd do it if I had a use for it.


Tempted, but not going.

Runcorn? Don't forget to add in the cost of wear and tear on body armour, number of cans of morlock repellant used... 

[dl6lr]

Surely it must be possible to write a script that will boot your PC and then load all of your 50 tabs  (50  ) automatically for you so that by the normal time of day when you would normally be at the PC, it was already running for you without all of that wasted power?

This rocket technology is called hibernate    And at least Firefox can reload all tabs on start, if you allow it to do so.
But Vince may have his reasons for his way. It would waste too much energy for me to leave the computer on all day (and it is relatively low power in idle), so I set up my computer to go to sleep on its own after a short time being unattended.

[dl6lr]

First, there was Linux. And it came in a box that said "Slackware".

Hmm, my first linux distro was SLS (Soft Landing System) on a lot of 5.25" disks. It replaced Minix on my disk. Must have the floppies somewhere. I think Slackware is some modern shit...

[Saskia]

let me look for my Sys V R2 ...

[Specmaster]

Surely it must be possible to write a script that will boot your PC and then load all of your 50 tabs  (50  ) automatically for you so that by the normal time of day when you would normally be at the PC, it was already running for you without all of that wasted power?

This rocket technology is called hibernate    And at least Firefox can reload all tabs on start, if you allow it to do so.
But Vince may have his reasons for his way. It would waste too much energy for me to leave the computer on all day (and it is relatively low power in idle), so I set up my computer to go to sleep on its own after a short time being unattended.

Totally agree with you, I use Firefox on Win10 and it loads up my most common tabs for me, but then again I do have a 360Mbps web connection.

[Cerebus]

Surely it must be possible to write a script that will boot your PC and then load all of your 50 tabs  (50  ) automatically for you so that by the normal time of day when you would normally be at the PC, it was already running for you without all of that wasted power?

This rocket technology is called hibernate    And at least Firefox can reload all tabs on start, if you allow it to do so.
But Vince may have his reasons for his way. It would waste too much energy for me to leave the computer on all day (and it is relatively low power in idle), so I set up my computer to go to sleep on its own after a short time being unattended.

In Vince's defence the one thing I have found flakiest in Linux in all the years (see below) I have been using it is sleep/hibernate functionality. It is very sensitive to you having the right hardware in the right combination.

First, there was Linux. And it came in a box that said "Slackware".

Hmm, my first linux distro was SLS (Soft Landing System) on a lot of 5.25" disks. It replaced Minix on my disk. Must have the floppies somewhere. I think Slackware is some modern shit...

My first Linux distribution wasn't a distribution. It was a single 1.44Mb floppy that booted Linux 0.26 (or it might have been 0.27) with the raw essentials on and from that point you were on your own. Installing it meant really knowing how to build a filesystem from scratch. I ran that for about a year (circa 1991/1992) on a box under my office desk with Wuarchive NFS mounted on it across the Internet, which is where everything else other than the raw essentials came from.

[med6753]

Got the Tek 212 mini pulled apart again. Pretty much traced the intermittent trace issue to the entire HV section dancing around. One minute reads correct -982V and another minute drops to -910V then back up again. That naturally causes focus issues and intensity issues. And of course while troubleshooting the damn thing goes nice and stable.



It's near impossible to safely probe the bottom board in the vicinity of the HV area so in looking over the schematic going to mass replace all the HV diodes and capacitors. I'm bound to get lucky with that tactic. I'll check the resistors and I may decide to mass replace them too.   

[mansaxel]

First, there was Linux. And it came in a box that said "Slackware".

Hmm, my first linux distro was SLS (Soft Landing System) on a lot of 5.25" disks. It replaced Minix on my disk. Must have the floppies somewhere. I think Slackware is some modern shit...

Yes, there is considerable hand-waving in the older history of Linux as written by yours truly. Mind you, I came to that party late; not until 1995 or so.