Test Equipment Anonymous (TEA) group therapy thread

[0culus]

Thanks for carrying forward with this; it's quite illuminating re: the P6100 probes... but I find myself wondering, given the difficulties of sampling in the 1nS neighborhood, how much of the distortion we're seeing is digital artifact...?

Technically the scope I'm using (Lecroy DDA-110 / LC574) has a rise time of 0.35nS (1Ghz). It's more than enough to test the poor little P6100 probe. But noise is minimal results are repeatable. Just compare the Kuman to the JinHao waveform, it's identical. Could do a run with averaging if you prefer but the overall distortion are going to be the same.

What's the nominal bit depth when sampling at that speed? I'll admit I'm ignorant of probably at least the last decade of development in DSO tech, but your traces did appear a bit clipped in both axes right around the transition regions; usually a sign that acquisition is operating right at the limits of resolution, which is why I asked.

On the other hand, it's entirely possible I'm misinterpreting what I see in the waveform based on outdated experience and seeing artifact where it isn't.  I mean yeah, still an apples-to apples comparison; the Tek probes and that homebrew FET probe are very clearly better. Just not sure how much better in real-world application.

mnem
Everybody needs something to believe in; I believe I'm gonna go take a nap.

Honestly, it really depends on how quantitative you want to be with your approach. For qualitative "that looks about right", you probably don't need high end probes.

[med6753]

Remember this scope? RCA WO-505A. Bought it on local CL last Summer. Paid $40 USD for it. It worked, sort of. Somewhat flaky and unstable. First order of business was to recap the power supply. It is a separate board so it should have been real easy. Got it done and lost horizontal sweep. Just a dot on the CRT. Checked over my work several times and found nothing wrong. So went searching for a manual/schematic and came up empty except for this place called “Vintage Manuals”. For $24 USD and $6 USD shipping they would send me a service manual. No thank you. So the scope went into the TEA closet.

Fast forward to now. Resumed search for a manual. Still no dice except for Vintage Manuals. Broke down and bought it. Should be here next week. Will go on the project list after the Heath OL-1 is done.

[mnementh]

Not strictly Test Equipment, but certainly related to TEA repairs, I purchased this Hitachi/Metabo power screwdriver on Shahriar's endorsement in one of the recent Signal Path episodes: https://www.amazon.com/gp/product/B07L78Y72J/

Looking forward to trying it. Unlike a lot of others, it has a very large selection of clutch settings down to very low torque so it should make disassembly and reassembly of test gear much easier.

   That thing is a effing abortion... I can see at least 6 glaring noob engineer "I'm an imbecile who doesn't actually use tools" design mistakes... and why the FUCK is the motor/gearhead portion so big/long? It could literally be HALF that size and do the job. 

mnem
*running away before the yuckyputz gets all over me*

[bitseeker]

Today a old switch that was used to toggle power to a 230V sunoy fan for fume extraction blowed .... this type of switch is very old and due to low separation between Neutral and Phase when swapping the button it arced, RCD tripped

Holy smokes, you're not kidding about it being an old switch. I'm surprised you were able to keep it going this long.

[med6753]

Damn it! Package from Mouser arrived at my local UPS hub this morning. And that's where it will sit until Tuesday. Rats! 

[med6753]

Not strictly Test Equipment, but certainly related to TEA repairs, I purchased this Hitachi/Metabo power screwdriver on Shahriar's endorsement in one of the recent Signal Path episodes: https://www.amazon.com/gp/product/B07L78Y72J/

Looking forward to trying it. Unlike a lot of others, it has a very large selection of clutch settings down to very low torque so it should make disassembly and reassembly of test gear much easier.

   That thing is a effing abortion... I can see at least 6 glaring noob engineer "I'm an imbecile who doesn't actually use tools" design mistakes... and why the FUCK is the motor/gearhead portion so big/long? It could literally be HALF that size and do the job. 

mnem
*running away before the yuckyputz gets all over me*

Don't hold back. Tell us what you REALLY think. 

[xrunner]

Damn it! Package from Mouser arrived at my local UPS hub this morning. And that's where it will sit until Tuesday. Rats! 

Yea, I hate it when that happens! 

[mnementh]

Damn it! Package from Mouser arrived at my local UPS hub this morning. And that's where it will sit until Tuesday. Rats! 

And of course, they didn't update until after closing time, so you can't go pick it up, right?

mnem
*FED-UPS Strikes Again*

[med6753]

Damn it! Package from Mouser arrived at my local UPS hub this morning. And that's where it will sit until Tuesday. Rats! 

And of course, they didn't update until after closing time, so you can't go pick it up, right?

mnem
*FED-UPS Strikes Again*

Early this morning when I last checked it was still in Syracuse. Didn't check again until now. Yes, they are closed. 

[Kosmic]

What's the nominal bit depth when sampling at that speed? I'll admit I'm ignorant of probably at least the last decade of development in DSO tech, but your traces did appear a bit clipped in both axes right around the transition regions; usually a sign that acquisition is operating right at the limits of resolution, which is why I asked.

On the other hand, it's entirely possible I'm misinterpreting what I see in the waveform based on outdated experience and seeing artifact where it isn't.  I mean yeah, still an apples-to apples comparison; the Tek probes and that homebrew FET probe are very clearly better. Just not sure how much better in real-world application.

mnem
Everybody needs something to believe in; I believe I'm gonna go take a nap.

The scope is 8bits but I'm not sure of the effective enob. So, I did couple more captures just for you 

First one is at 4GS/s Dot mode, RAW on top (Green), Averaged at the bottom. Each dot is a different capture.


Now same scenario but with linear interpolation between the dots.


And last I increased capture rate to 10GS/s (Interleaved). So with higher capture rate the waveform is smoother, but still overall the same thing.


So averaging and increasing capture rate definitely help with the noise.

A different way of visualizing the data is the “analog” or “color” mode. Also give an impression of smoothness but the underlying data is the same. On my side I prefer linear interpolation.

[mnementh]

That's exactly what I was expecting to see in the rise & fall regions; but man, the transition areas have a LOT more DP density than I was expecting. I have NO PROBLEM accepting that plot as a reasonable approximation of the actual signal with very little artifacting. 

mnem
Dayumm.

[Kosmic]

Look like it's in really good shape. I like the front panel!

[0culus]

Not strictly Test Equipment, but certainly related to TEA repairs, I purchased this Hitachi/Metabo power screwdriver on Shahriar's endorsement in one of the recent Signal Path episodes: https://www.amazon.com/gp/product/B07L78Y72J/

Looking forward to trying it. Unlike a lot of others, it has a very large selection of clutch settings down to very low torque so it should make disassembly and reassembly of test gear much easier.

   That thing is a effing abortion... I can see at least 6 glaring noob engineer "I'm an imbecile who doesn't actually use tools" design mistakes... and why the FUCK is the motor/gearhead portion so big/long? It could literally be HALF that size and do the job. 

mnem
*running away before the yuckyputz gets all over me*

It's honestly not as big as the pictures make it seem. Feels pretty nice in the hand.

[bitseeker]

I found a picture of the one I owned one a few years back which I paid a £10 for which I thoroughly regret selling if I'm honest:

Yep, I know the feeling. It's a risk we take when feeding the TEA monster.

[bitseeker]

Remember this scope? RCA WO-505A. Bought it on local CL last Summer. Paid $40 USD for it. It worked, sort of. Somewhat flaky and unstable. First order of business was to recap the power supply. It is a separate board so it should have been real easy. Got it done and lost horizontal sweep. Just a dot on the CRT. Checked over my work several times and found nothing wrong. So went searching for a manual/schematic and came up empty except for this place called “Vintage Manuals”. For $24 USD and $6 USD shipping they would send me a service manual. No thank you. So the scope went into the TEA closet.

Fast forward to now. Resumed search for a manual. Still no dice except for Vintage Manuals. Broke down and bought it. Should be here next week. Will go on the project list after the Heath OL-1 is done.

Actually, I don't remember it, but I like it. Very shiny. If Power Designs made scopes, they might look like that one. I think PD used the same binding posts.

Oh, no. Must stop thinking about such things.

I shall look forward to its resurrection.

[beanflying]

I did promise no new HP logos for a day or two but adding a Tek one is different  Needs a slightly deeper engrave due to the finer detail on the next one but overall it works. Holding up the HP one is the slabbed Laser Cut Acrylic base, lots of benifits over the 3DP in this case, faster, heavier and it opens up different material options such as timber etc.

The SVG of the Logo I made is in the Zip if anyone wants to use it elsewhere.

[bitseeker]

So cool. If you decide to make lots of these, samples need to show up in Dave's mailbag.

[mnementh]

Not strictly Test Equipment, but certainly related to TEA repairs, I purchased this Hitachi/Metabo power screwdriver on Shahriar's endorsement in one of the recent Signal Path episodes: https://www.amazon.com/gp/product/B07L78Y72J/

Looking forward to trying it. Unlike a lot of others, it has a very large selection of clutch settings down to very low torque so it should make disassembly and reassembly of test gear much easier.

   That thing is a effing abortion... I can see at least 6 glaring noob engineer "I'm an imbecile who doesn't actually use tools" design mistakes... and why the FUCK is the motor/gearhead portion so big/long? It could literally be HALF that size and do the job. 

mnem
*running away before the yuckyputz gets all over me*

It's honestly not as big as the pictures make it seem. Feels pretty nice in the hand.

meh. I’ve bought and got rid of dozens just like it; the whole design is a recycled clusterfuck from years gone by.

Black & Decker tried the flip-out grip decades ago; they abandoned it because they got reamed by the customers over the built-in pinch points that make the design a blood-blister factory.

The rocker paddle on the side means it’s only really good in screwdriver mode; in pistol mode for righties it’s inconvenient, for lefties it’s unusable.

Proprietary single-cell packs in this day & age? 18650 cells and chargers are cheap and more common than D cells anymore.

And single-cell means slow as flurp; probably 450-550 RPM.

That pregnant motor/gearbox section tells me that even though they’re charging “real tool” prices, they couldn’t be arsed to actually design a new tool; they just made a flip-out shell for some discontinued drill gearbox and 1S-voltage motor.

That thing is no more than a Versa-Pack B&D electric screwdriver in Hitachi green.   

mnem
meh and a half.

[med6753]

I did promise no new HP logos for a day or two but adding a Tek one is different  Needs a slightly deeper engrave due to the finer detail on the next one but overall it works. Holding up the HP one is the slabbed Laser Cut Acrylic base, lots of benifits over the 3DP in this case, faster, heavier and it opens up different material options such as timber etc.

The SVG of the Logo I made is in the Zip if anyone wants to use it elsewhere.

Cool! I want one. 

[mnementh]

Urrrrggghh.

This is not good. I accidentally plugged my old spinning rust drive into an AHCI SATA port; obviously it’s didn’t boot but ever since it’s been flaky. Doesn’t resume from sleep properly, showing up as a Samsung Evo 850 SSD due to wrong driver evidently. Maybe a cross-connected file, I dunno.

Uninstalled the drive to force reinstall of the correct driver and running a CHKDSK /R; has been stuck at 17% for however the eff long it took me to tap out that last post and this one on my iPad. 

I’m going to bed.

mnem
 

[bitseeker]

Just saw this (some NOS Tek CRTs): https://www.eevblog.com/forum/buysellwanted/fs-new-in-box-old-tektronix-crts/

[VK5RC]

My 'conceit' re HP 3400A has come back to bite me!
I hadn't used it for a long time, so I plugged it in and the meter pegged - typically a fault in one of the pair of thermocouples. Fortunately the parts unit's t-couples / board were working fine - so just a board shuffle - I have managed to find some NOS of 2 matched pairs of t-couples for not crazy money - so will have a go at fixing it - they seem to be a common failure in this unit.

Re the Hitachi driver unit - I have one -happy with it - good for when you have to take out 50 screws in plastic - the torque control quite nice - but I use hand screwdrivers almost all the time really - biological torque control and no batteries! Re-charging much more fun!
Rob

[med6753]

Just saw this (some NOS Tek CRTs): https://www.eevblog.com/forum/buysellwanted/fs-new-in-box-old-tektronix-crts/

By virtue of my parts mules I already have spare CRT's for 465B and 2430. What I didn't realize is the 2430 and 2465 use the same CRT. I'll have to check that. If yes, then both the 2465's are covered too.

The 7603 CRT. I'll have to check and see if my military 7603N takes the same CRT. I assume it does but you know what happens when you ass-u-me. 

Now if he had a spare 7904 CRT I'd definitely be talking to him. 

[beanflying]

I did promise no new HP logos for a day or two but adding a Tek one is different  Needs a slightly deeper engrave due to the finer detail on the next one but overall it works. Holding up the HP one is the slabbed Laser Cut Acrylic base, lots of benifits over the 3DP in this case, faster, heavier and it opens up different material options such as timber etc.

The SVG of the Logo I made is in the Zip if anyone wants to use it elsewhere.

Cool! I want one.

Can be done. Just sorting out some full 8x4 sheets of extra material. But flatpack, Kit of fasteners and brass feet, five 3mm slabs of translucent grey for the base, display panel of choice, 100mm of white 5050 (because I have it). Circa $25 USD posted worldwide likely. Could slip a second one in the same parcel for around $15 extra.

Leaning toward making them with a single sided PCB to a micro USB over the 12V tape and wire out (bodgey ) in the slightly longer term for general use but most of us nerdy mob will have plenty of old 12v wallwarts laying around so it save a $ and uses up trash.

[med6753]

I did promise no new HP logos for a day or two but adding a Tek one is different  Needs a slightly deeper engrave due to the finer detail on the next one but overall it works. Holding up the HP one is the slabbed Laser Cut Acrylic base, lots of benifits over the 3DP in this case, faster, heavier and it opens up different material options such as timber etc.

The SVG of the Logo I made is in the Zip if anyone wants to use it elsewhere.

Cool! I want one.

Can be done. Just sorting out some full 8x4 sheets of extra material. But flatpack, Kit of fasteners and brass feet, five 3mm slabs of translucent grey for the base, display panel of choice, 100mm of white 5050 (because I have it). Circa $25 USD posted worldwide likely. Could slip a second one in the same parcel for around $15 extra.

Leaning toward making them with a single sided PCB to a micro USB over the 12V tape and wire out (bodgey ) in the slightly longer term for general use but most of us nerdy mob will have plenty of old 12v wallwarts laying around so it save a $ and uses up trash.

Well let me know when you sort out the total cost via PM and I'll get the cash (USPS money order) in route to you pronto.  Obviously I want to Tek logo.  And just one is fine.