Author Topic: Test Equipment Anonymous (TEA) group therapy thread  (Read 4307163 times)

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Offline Cerebus

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #72700 on: October 20, 2020, 04:34:02 pm »
(I am having this argument with someone at the moment who wants everything covered but went purple when I suggested I'd just take a picture of the screen with my phone  :-DD)

Not a bad example of the old dictum: if you think encryption will solve your problem then you don't understand encryption and you don't understand your problem.

There's another layer to that which has appeared recently: If you think decryption will solve your problem then you don't understand encryption and you don't understand your problem.

So someone wants to MITM all TLS traffic because they don't trust humans. They forget that it increases the risk ten-fold for legitimate traffic and by the time the event has occurred, the data has been exfiltrated anyway and lastly that the entire system is flawed when it comes to information classification anyway. I suggested they fixed the latter but that means an ego needs to be kicked.

Officially not my funeral soon so I'm speaking my mind quite a lot  :-DD

Expalin 'covert channels' to them, and that TLS is riddled with them, therefore the MITM box could quietly give away everything, and watch them turn green.
Anybody got a syringe I can use to squeeze the magic smoke back into this?
 

Offline Specmaster

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #72701 on: October 20, 2020, 04:34:09 pm »
But that post was me needling Specmaster over his tribulations with that PL310; it was a backhanded suggestion as to how he could make all that misery just go away.  ;)

Of course, Spec did not take the bait.  :-DD
That's because he knows the fight is worth it and the noise floor is not :)

That energy might be better spent turning that one into a cheap battery charger and getting a proper lab supply>:D



mnem

Nope, Spec is not rising to the bait, there is nothing fundamentally wrong with a TTi power supply, its noise level is sufficiently low enough for my uses. As to that bloody fire starter of a power supply that can, to coin bd's phrase, that can fuck right off into the stupid bin.  :-DD
Who let Murphy in?

Brymen-Fluke-HP-Thurlby-Heathkit-Thander-Tek-Extech-Black Star-GW-Advance-Avo-Kyoritsu-Amprobe-ITT-Robin-TTi
 

Offline bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #72702 on: October 20, 2020, 04:46:27 pm »
The only way to combat this scenario, that I have seen used in practice, was figured out in the 1970s in Multics. You attach security labels to all your files, you attach security labels to all your terminals, someone who logs into one of those terminals gets their security labels (and of processes they run) downgraded to those of the terminal. Try and display a 'secret' document on a 'restricted' terminal - system stops you (and logs it). If you have 'secret' graded terminals you put them in a room with an ugly, uncompromising guard outside who relieves you of any cameras, notebooks etc. and strip searches you on the way out to check that you haven't found a way to write the recipe for Kentucky Fried Chicken down the inside of your thigh.

Security is, first and foremost, a people problem and always will be; attempts to solve it with just computer technology will fail. Encryption is only ever good for ensuring that stuff is secure when it's being transported through, or stored in, somewhere that isn't secure. Proper 'secret' level security is always expensive.

Yep spot on. I built a DMS years ago based on that principle but with some extensions for time-windowing access, working groups and better auditing :)

Expalin 'covert channels' to them, and that TLS is riddled with them, therefore the MITM box could quietly give away everything, and watch them turn green.

I did raise that one but the vendor persuaded them that their product is immune to such things. It is not immune to tcpdump which I demonstrated because someone left their SSH key wide open on a machine I had control over so I just logged in to the thing with it  :-DD



My favourite find in recent years was when I pointed a Software Composition Analysis product at itself (BlackDuck) and it found some holes. They hadn't even run their own product on their own code and it was shipping a vulnerable Tomcat implementation :-DD

Whole software industry is a fucking joke and I'll be glad when I'm out permanently.
 

Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #72703 on: October 20, 2020, 04:58:59 pm »
Like Teh Caek, Internet Security is a lie. The best you can hope for is to make your very important secrets enough hassle to get hold of that ne'er-do-wells get bored and move on. :o

Then you only have to worry about the people who really want what you have.  :palm:

mnem
 
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Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #72704 on: October 20, 2020, 05:00:54 pm »
From the SAVE MY ASS!!! Dept...

      

Had the opportunity to test the "Power Failure Print Recovery" feature in Marlin 1.9.x this morning; power went out at ~5AM for a couple hours, and this print was at approx 90%. That little booger and a single-layer-height line of overextrusion from printing to a fully-cooled part was the only evidence of any misdoing. Cleaned up, a very usable part; though some repeating blebs around the corners show that I do need to clean and tighten the X-Y tracks/rollers after running it pretty much nonstop for 4 days.

Well done, Diggro.  :clap:

mnem
*off to engage in that illusion known as lunchtime*
 
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Online med6753

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #72705 on: October 20, 2020, 05:06:35 pm »
So one of my Fluke 8800A's needs a minor repair. The 200mV/200 ohm range LED is intermittent. Sometimes comes on, sometimes doesn't, and even sometimes randomly flashes. So today I figured I'd pull it apart and see what's up.

Wouldn't you know it. The manual that I have is complete EXCEPT for the schematic of the display panel.  :wtf: :palm: So off to Artek Manuals and pay the $8 USD for a download. At least I know it will be a good copy and complete. But they "lock down" their PDF's and you can't copy/paste pages or portions of pages and drop into a separate file. Oh well.  :-//   

Perhaps this can help you:

https://www.wikihow.com/Unlock-a-Secure-PDF-File

You can also get very usable results using the snipping tool to screencap directly from your .pdf viewer.

mnem
 :-/O

Where does one find this alleged snipping tool?  :-//

Edit, Artek Manuals responded and gave me the download link within 20 minutes of placing the order. Can't ask for better service than that.  :-+
« Last Edit: October 20, 2020, 05:13:17 pm by med6753 »
An old gray beard with an attitude.
 

Offline McBryce

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #72706 on: October 20, 2020, 05:22:37 pm »
Worst case you can print it and rescan it, but you could try something like PDF24 Creator... The sheep can help you! (Note to members from Wales / New Zealand / etc. - No! Not that way! Stop it!) https://en.pdf24.org/


McBryce.
« Last Edit: October 20, 2020, 05:36:29 pm by McBryce »
 

Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #72707 on: October 20, 2020, 05:27:35 pm »
So one of my Fluke 8800A's needs a minor repair. The 200mV/200 ohm range LED is intermittent. Sometimes comes on, sometimes doesn't, and even sometimes randomly flashes. So today I figured I'd pull it apart and see what's up.

Wouldn't you know it. The manual that I have is complete EXCEPT for the schematic of the display panel.  :wtf: :palm: So off to Artek Manuals and pay the $8 USD for a download. At least I know it will be a good copy and complete. But they "lock down" their PDF's and you can't copy/paste pages or portions of pages and drop into a separate file. Oh well.  :-//   

Perhaps this can help you:

https://www.wikihow.com/Unlock-a-Secure-PDF-File

You can also get very usable results using the snipping tool to screencap directly from your .pdf viewer.

mnem
 :-/O

Where does one find this alleged snipping tool?  :-//



https://support.microsoft.com/en-us/windows/use-snipping-tool-to-capture-screenshots-00246869-1843-655f-f220-97299b865f6b

Also PowerToys, because fukkin' awesome: https://github.com/microsoft/PowerToys

https://www.howtogeek.com/665780/all-microsofts-powertoys-for-windows-10-explained/

And the old Image resizer PowerToy for those still flogging Win-not-10:  https://www.bricelam.net/ImageResizer/

mnem
*occasionally useful*
« Last Edit: October 20, 2020, 05:39:31 pm by mnementh »
 

Offline Kosmic

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #72708 on: October 20, 2020, 05:38:55 pm »
So one of my Fluke 8800A's needs a minor repair. The 200mV/200 ohm range LED is intermittent. Sometimes comes on, sometimes doesn't, and even sometimes randomly flashes. So today I figured I'd pull it apart and see what's up.

Wouldn't you know it. The manual that I have is complete EXCEPT for the schematic of the display panel.  :wtf: :palm: So off to Artek Manuals and pay the $8 USD for a download. At least I know it will be a good copy and complete. But they "lock down" their PDF's and you can't copy/paste pages or portions of pages and drop into a separate file. Oh well.  :-//   

Perhaps this can help you:

https://www.wikihow.com/Unlock-a-Secure-PDF-File

You can also get very usable results using the snipping tool to screencap directly from your .pdf viewer.

mnem
 :-/O

Where does one find this alleged snipping tool?  :-//



https://support.microsoft.com/en-us/windows/use-snipping-tool-to-capture-screenshots-00246869-1843-655f-f220-97299b865f6b

Also PowerToys, because fukkin' awesome: https://github.com/microsoft/PowerToys

mnem
*occasionally useful*

Or "Shift" + "Windows Key" + "S"

Only on win10 though.
 

Offline Specmaster

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #72709 on: October 20, 2020, 05:40:32 pm »
Well I guess it time to decide what to do with the Thurlby PL310 after all the flipping time I've spent on it and the trouble its been, so I'll just have to put it on one side and wait for the time being........ until I need to use it. Yes that does indeed mean that its fixed and working again and ready for active duty, the little beauty.

It was offered to me by Ice-Tea almost a month ago now and jumped at the chance of having another nice piece of TTi gear at my disposal. It was just as Ice-Tea described it, totally unresponsive with the output voltage displaying 40.95V with no control over it at all. Plugging in my Brymen revealed that the true output voltage was some 51V, a far cry from its supposed maximum of 32.1V.

Next there was the searching around on the internet for the service manual and after many downloads, eventually found one that had resemblance to the boards fitted inside it. Once it arrived, I opened it up and was surprised to see it looking like new inside, no sign of the usual dust and grime. Started pulling a few caps out and testing them, some had a ESR of 12 \$\Omega\$ so that was not ideal, so ordered a complete set electrolytics for it. Then discovered that the 2 regulators on the driver board had decided to curl their toes up and die along with the pass transistor (2N3055) so these were also ordered as the Op Amp was also inexpensive, order that as well.

The parts came in, and they were all fitted, and I was very pleased to see that I now had full control over the voltage on the controls, however that elation was short-lived as it was fine as long as the unit did not have a load connected. Even a 1K resistor was enough of a load to bring the voltage crashing down to 1.8V  :wtf: Then started a head long dive into a rabbit hole, pulling everything on the main board off that had anything to do with the voltage and current controls, everything tested OK and yet the problem still existed. Next I dragged out the microscope and started checking for cracks in the traces and dry joints, then reflowing all the joints, still the problem persisted. I even got to the stage where I suspected all the Zeners on the board, although logic, along with a few members, told me that they were fine.

I even started talking to TTi technical dept, and they told me that they nobody working there now that knew about the "brown" power supplies but did furnish me with a service manual for the brown series of PL310's. The manual, as it turned was for the older models series 1 and 2 of those supplies. I sent them photos of the boards, and they then identified it as their newer grey series, even though it was in a brown case. A suitable service was then emailed to me along with an explanation that, although it was in a brown case, it was really a grey series and when they introduced the new model, they had a load of brown cases and they decided to use them up first.

Edit: this is split into 2 parts because of the number of photos.

The dammed forum attachment bug got my photos and screwed up the order they were shown in, rectified that, thats why mnem sussed it out.
« Last Edit: October 20, 2020, 06:18:16 pm by Specmaster »
Who let Murphy in?

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Offline Robert763

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #72710 on: October 20, 2020, 05:40:46 pm »
Another problem management and admins make is to restrict everyday data that does not need to be restricted. The restrictions become a pain and workers find work-arounds for stuff that does not matter, but then the work-arounds get used on stuff that does matter. Another is enforcing "complex" passwords that humans can't remember so they write them down |O
Same with physical security. Years ago I was with the boss viewing a building the company was thinking of buying. The server room had RFID access control but the tags we were given were not on the list. Took me less tthan a minute to get in. They had mounted the reader on a plate so I unscrewed that and operated the door release mistakes made were mounting on a plate bypassed the reader anti-tamper (no I'm not saying what it was) and they had made the wiring connectons obvious :palm:

Aircraft software - Boeing 737 bug where if you were on a ILS approach on a specfic heading in a number of specific ranges of lat and long ALL FIVE primary flight and navigation displays go blank :scared:     Fortunatly there were only about a dozen runways on the right heading in the affected locations.
 
 

Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #72711 on: October 20, 2020, 05:44:09 pm »


https://support.microsoft.com/en-us/windows/use-snipping-tool-to-capture-screenshots-00246869-1843-655f-f220-97299b865f6b

Also PowerToys, because fukkin' awesome: https://github.com/microsoft/PowerToys

https://www.howtogeek.com/665780/all-microsofts-powertoys-for-windows-10-explained/

And the old Image resizer PowerToy for those still flogging Win-not-10:  https://www.bricelam.net/ImageResizer/

mnem
*occasionally useful*

Or "Shift" + "Windows Key" + "S"   Only on win10 though.
Yeah... I still keep Snipp, Paint, Calc & WordPad on my toolbar.  :P

mnem
Old dwagons and old habits die hard. ;)
 

Offline bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #72712 on: October 20, 2020, 05:48:19 pm »
Another problem management and admins make is to restrict everyday data that does not need to be restricted. The restrictions become a pain and workers find work-arounds for stuff that does not matter, but then the work-arounds get used on stuff that does matter. Another is enforcing "complex" passwords that humans can't remember so they write them down |O
Same with physical security. Years ago I was with the boss viewing a building the company was thinking of buying. The server room had RFID access control but the tags we were given were not on the list. Took me less tthan a minute to get in. They had mounted the reader on a plate so I unscrewed that and operated the door release mistakes made were mounting on a plate bypassed the reader anti-tamper (no I'm not saying what it was) and they had made the wiring connectons obvious :palm:

Aircraft software - Boeing 737 bug where if you were on a ILS approach on a specfic heading in a number of specific ranges of lat and long ALL FIVE primary flight and navigation displays go blank :scared:     Fortunatly there were only about a dozen runways on the right heading in the affected locations.

That door thing reminds me of the "security consultants" that we had come in once to check machine room security at a defence facility. One of them walked about a metre back and shouldered the door and it opened right up :-DD. Had to replace 100 odd doors due to that  :-DD
 
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Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #72713 on: October 20, 2020, 05:50:45 pm »
Well I guess it time to decide what to do with the Thurlby PL310 after all the flipping time I've spent on it and the trouble its been, so I'll just have to put it on one side and wait for the time being........ until I need to use it. Yes that does indeed mean that its fixed and working again and ready for active duty, the little beauty...

Okay... so what eventually was the culprit...? Or are you working up a big post and gonna leave us hanging 'til the big reveal...? 

mnem
he would never do that. >:D
 

Offline Specmaster

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #72714 on: October 20, 2020, 05:53:15 pm »
Part 2 of the PL310 saga.

PL310 part 2
Then I decided to revisit everything as I must have missed something along the way and working backwards until I reached the pass transistor, the 2N3055, and found that all the problems had been of my own making, oh the shame of it  :palm: I had missed wired it and had the base and emitter leads reversed  :wtf:

Reversed these and powered up, bingo it is only fecking working, my only defence is that I must have had a senior moment when soldering the leads up.  :-DD :-DD :-DD

When its been warmed, the reading do agree with each other to with 1 mV.
Who let Murphy in?

Brymen-Fluke-HP-Thurlby-Heathkit-Thander-Tek-Extech-Black Star-GW-Advance-Avo-Kyoritsu-Amprobe-ITT-Robin-TTi
 
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Offline Specmaster

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #72715 on: October 20, 2020, 05:56:52 pm »
Well I guess it time to decide what to do with the Thurlby PL310 after all the flipping time I've spent on it and the trouble its been, so I'll just have to put it on one side and wait for the time being........ until I need to use it. Yes that does indeed mean that its fixed and working again and ready for active duty, the little beauty...

Okay... so what eventually was the culprit...? Or are you working up a big post and gonna leave us hanging 'til the big reveal...? 

mnem
he would never do that. >:D
haha, yeah, the culprit was ME.
Who let Murphy in?

Brymen-Fluke-HP-Thurlby-Heathkit-Thander-Tek-Extech-Black Star-GW-Advance-Avo-Kyoritsu-Amprobe-ITT-Robin-TTi
 
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Offline bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #72716 on: October 20, 2020, 05:58:27 pm »
 :-DD We’ve all done it  :-DD

You hit the jackpot with that. It’s one of the nice series in an old case  :-+
 
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Offline nfmax

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #72717 on: October 20, 2020, 06:00:47 pm »
Another problem management and admins make is to restrict everyday data that does not need to be restricted. The restrictions become a pain and workers find work-arounds for stuff that does not matter, but then the work-arounds get used on stuff that does matter. Another is enforcing "complex" passwords that humans can't remember so they write them down |O
Same with physical security. Years ago I was with the boss viewing a building the company was thinking of buying. The server room had RFID access control but the tags we were given were not on the list. Took me less tthan a minute to get in. They had mounted the reader on a plate so I unscrewed that and operated the door release mistakes made were mounting on a plate bypassed the reader anti-tamper (no I'm not saying what it was) and they had made the wiring connectons obvious :palm:

Aircraft software - Boeing 737 bug where if you were on a ILS approach on a specfic heading in a number of specific ranges of lat and long ALL FIVE primary flight and navigation displays go blank :scared:     Fortunatly there were only about a dozen runways on the right heading in the affected locations.

That door thing reminds me of the "security consultants" that we had come in once to check machine room security at a defence facility. One of them walked about a metre back and shouldered the door and it opened right up :-DD. Had to replace 100 odd doors due to that  :-DD

Why the "quotes"? That security consultant was clearly worth every penny!
 
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Offline Cerebus

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #72718 on: October 20, 2020, 06:04:35 pm »
The only way to combat this scenario, that I have seen used in practice, was figured out in the 1970s in Multics. You attach security labels to all your files, you attach security labels to all your terminals, someone who logs into one of those terminals gets their security labels (and of processes they run) downgraded to those of the terminal. Try and display a 'secret' document on a 'restricted' terminal - system stops you (and logs it). If you have 'secret' graded terminals you put them in a room with an ugly, uncompromising guard outside who relieves you of any cameras, notebooks etc. and strip searches you on the way out to check that you haven't found a way to write the recipe for Kentucky Fried Chicken down the inside of your thigh.

Security is, first and foremost, a people problem and always will be; attempts to solve it with just computer technology will fail. Encryption is only ever good for ensuring that stuff is secure when it's being transported through, or stored in, somewhere that isn't secure. Proper 'secret' level security is always expensive.

Yep spot on. I built a DMS years ago based on that principle but with some extensions for time-windowing access, working groups and better auditing :)

Multics also had all those, and more. Multics is still worthy of study for hints of how to do things from a security perspective now (53 years after its first delivery). It was designed as a computing utility (utility in the sense of the electric company et al) in the days when people only foresaw large centralised computer systems. As such it was designed to be used by mutually distrustful groups, and to achieve military grades of security - it was the first system to get Orange Book B2 accreditation. It had many worthy and well thought out features (like a system security administrator role account that couldn't do anything except run the security tools). Starting point for finding more: https://multicians.org/security.html.


Quote
My favourite find in recent years was when I pointed a Software Composition Analysis product at itself (BlackDuck) and it found some holes. They hadn't even run their own product on their own code and it was shipping a vulnerable Tomcat implementation :-DD

Whoops!  :)  The whole recent tendency to throw whole big third party subsystems (e.g. Tomcat) into products is just asking for trouble.
Anybody got a syringe I can use to squeeze the magic smoke back into this?
 

Offline Specmaster

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #72719 on: October 20, 2020, 06:14:37 pm »
:-DD We’ve all done it  :-DD

You hit the jackpot with that. It’s one of the nice series in an old case  :-+
Good job I never put the collector on the base, that sucker has 51V on it, lucky the wire was just too short to reach eh?  >:D ::) Yeah I'm really pleased about it being newer than it looks.
Who let Murphy in?

Brymen-Fluke-HP-Thurlby-Heathkit-Thander-Tek-Extech-Black Star-GW-Advance-Avo-Kyoritsu-Amprobe-ITT-Robin-TTi
 
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Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #72720 on: October 20, 2020, 06:18:13 pm »
Well I guess it time to decide what to do with the Thurlby PL310 after all the flipping time I've spent on it and the trouble its been, so I'll just have to put it on one side and wait for the time being........ until I need to use it. Yes that does indeed mean that its fixed and working again and ready for active duty, the little beauty...

Okay... so what eventually was the culprit...? Or are you working up a big post and gonna leave us hanging 'til the big reveal...? 

mnem
he would never do that. >:D
haha, yeah, the culprit was ME.

LOL... sure proof that you are a engineer, even if only in spirit.  :-DD

Well done!  :clap:

mnem
 :-DMM

« Last Edit: October 20, 2020, 08:49:09 pm by mnementh »
 

Offline Specmaster

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #72721 on: October 20, 2020, 06:20:13 pm »
Well I guess it time to decide what to do with the Thurlby PL310 after all the flipping time I've spent on it and the trouble its been, so I'll just have to put it on one side and wait for the time being........ until I need to use it. Yes that does indeed mean that its fixed and working again and ready for active duty, the little beauty...

Okay... so what eventually was the culprit...? Or are you working up a big post and gonna leave us hanging 'til the big reveal...? 

mnem
he would never do that. >:D
haha, yeah, the culprit was ME.

LOL... sure proof that you are a engineer, even if only in spirit.  :-DD

mnem
 :-DMM


Hey, I resemble that remark!
Who let Murphy in?

Brymen-Fluke-HP-Thurlby-Heathkit-Thander-Tek-Extech-Black Star-GW-Advance-Avo-Kyoritsu-Amprobe-ITT-Robin-TTi
 
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Offline AVGresponding

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #72722 on: October 20, 2020, 06:20:49 pm »
Part 2 of the PL310 saga.

PL310 part 2
Then I decided to revisit everything as I must have missed something along the way and working backwards until I reached the pass transistor, the 2N3055, and found that all the problems had been of my own making, oh the shame of it  :palm: I had missed wired it and had the base and emitter leads reversed  :wtf:

Reversed these and powered up, bingo it is only fecking working, my only defence is that I must have had a senior moment when soldering the leads up.  :-DD :-DD :-DD

When its been warmed, the reading do agree with each other to with 1 mV.

Sounds like you've earned a nice cup of tea
nuqDaq yuch Dapol?
Addiction count: AVO-BlackStar-Brymen-Fluke-Hameg-HP-Keithley-IsoTech-Mastech-Megger-Micronta-Solartron-Tektronix-Thurlby-Time Electronics-TTi-UniT
 
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Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #72723 on: October 20, 2020, 06:31:28 pm »
:-DD We’ve all done it  :-DD

You hit the jackpot with that. It’s one of the nice series in an old case  :-+
Good job I never put the collector on the base, that sucker has 51V on it, lucky the wire was just too short to reach eh?  >:D ::) Yeah I'm really pleased about it being newer than it looks.
That's NOT how emitter-follower circuit is supposed to work...   :-DD

I think it's time for a coat of not-baby-poop-colored paint!

mnem
 :popcorn:

 
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Offline Specmaster

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #72724 on: October 20, 2020, 06:51:58 pm »
Well thats alright then, because it didn't work  :-DD
Who let Murphy in?

Brymen-Fluke-HP-Thurlby-Heathkit-Thander-Tek-Extech-Black Star-GW-Advance-Avo-Kyoritsu-Amprobe-ITT-Robin-TTi
 
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