Test Equipment Anonymous (TEA) group therapy thread

[Specmaster]

My HP3468A from that treasure trove in Farmingdale USA arrived today and once again due to diligence in examining the said photos and description has paid off handsomely, I now have another fully working and with in specification as regards to its calibration, another 5.5 digit meter. There's not a ding or scratch on it so cosmetically its in very good condition other than some dimwit has used a permanent marker on the top of it, but I believe I can remove or severely reduce the effect of that.

It however came with 4 broken spacers inside that hold the PCB in place, these as it happens are not required as it is held in with 4 screws anyway so these will be removed later and some photos taken for you guys to peruse. The only other thing is that it did not come with the internal battery and charging option, which I did originally think it did, thats not a major issue however as I will still have a HP3466A with that option if I need it.

In other news, I received today the other system board for the Tek TDS210 that I acquired as part of dual scope deal, the second scope was sold as "for spares" and now I have for a while 3 of these TDS210 scopes all working before I decide which ones to pass on again.

I also got myself 2 lovely Roberts mains radios recently FOC and now they are realigned, tuned up and just wanting on a couple of knobs and they will be ready for passing again, so its been a good day so far   

[mnementh]

In Other News...

   Been working on & off all day to design myself a meter stand in SketchUp... teaching myself by doing  for to print it up, since my DE-5000 is on the way. 

All I can say is... this is software that is clearly made by and for architects and materials engineers, NOT for human beings with a wetware brain. It isn't just counter-intuitive... it is anti-intuitive.  Every... goddamn... step... of... the... way... it had to shit on me in some fashion.     I've finally found a piece of software that is as much of an outright dicksore to use as Eagle. 

mnem
"Everybody needs something to believe in; I believe I'm going to bed." ~me

Aaaand the joy keeps on coming. Got everything set up to print; things actually went quite well. Set the printer up on my bench, leveled it, put up a curtain rod with my spool of filament since I knew I was printing a tall object... all before my first cuppa coffee. Then I put the card with my object in the printer and it all turned to shit.

The build volume in the firmware in my printer is still set to the generic stock figures of 300 x 300 x 400; the Tornado will actually do 310 x 320 x 400, and the difference between the two is the "margin" that Cura REFUSES to slice anything 300mm wide otherwise. Evidently Cura includes that margin on the finished GCODE; as the printer says the file dimensions are too big. 

Of course you can't reset the build volume from the front panel; that would be too easy. 

I have to plug the damned thing into a USB on my PC and learn how to use the freaking Marlin control panel... or do everything from the control line in the Arduino console like they did in the stone age. 

mnem
*Feeling like I'm the dead horse smoothee* 

[Cerebus]

...tried to mansplain it away to this dumb hick country boy that they didn't even need ...

As my late friend Fred Wedlock used to say, in his pronounced West Country burr: "Just because we sounds like we walk through it all the time doesn't mean that we 'as it between our ears."

[mnementh]

...tried to mansplain it away to this dumb hick country boy that they didn't even need ...

As my late friend Fred Wedlock used to say, in his pronounced West Country burr: "Just because we sounds like we walk through it all the time doesn't mean that we 'as it between our ears."

Yup. Of course, my inner voice is saying "Well if you don't need my permission, why the flupp are you weaseling your way up to my door for my signature?"

Uneducated doesn't mean stupid; and the existence of MBAs is proof that imbeciles can get a degree. 

mnem
"So this is a degree in buzzwords and making numbers lie? No wonder it pays so well." ~ me

[neo]

Tables done, at least the table bit itself, only my camera crapped out so i can't furnish you with pictures.

Imagine a picture of a rather large hunk of dead tree here.

[mnementh]

mnem
 

[bitseeker]

Sometimes a TEA monster resurfaces...

https://www.eevblog.com/forum/buysellwanted/ebay-large-lot-75-100-units-no-reserve/

[Berni]

Sometimes a TEA monster resurfaces...

https://www.eevblog.com/forum/buysellwanted/ebay-large-lot-75-100-units-no-reserve/

Damn you! Now i see some other items from that seller that i want now.

[bitseeker]

[Ice-Tea]

I'm about to rent office space so I have enough space for the gear I'm selling.

Can I join the club? 

[tautech]

I'm about to rent office space so I have enough space for the gear I'm selling.

Can I join the club? 

Oh goodie, another TEA enabler ! 
Welcome aboard.

[Ice-Tea]

Hou want a link to my ebay, don 't you?

DONT YOU?

[xrunner]

I'm about to rent office space so I have enough space for the gear I'm selling.

Can I join the club? 

Can you be a member of the club? A member?

I think you just became eligible to become the president & CEO.  .

[tautech]

I'm about to rent office space so I have enough space for the gear I'm selling.

Can I join the club? 

Can you be a member of the club? A member?

I think you just became eligible to become the president & CEO.  .

Until Toploser decides to join up ! 

[Specmaster]

Here are a few photos of the HP3468A that I promised you earlier today, the marker on the top of the meter that I mentioned can be seen in the first photo and you'll notice that the permanent mark has been erased using nothing more or less than a good old magic sponge eraser (dry), very pleased with the result. Might remove the sticker later using WD-40.

Going by the date codes on the chips, this was made around the later part of 1983 and I never had to do any cleaning this, it really was as clean it looks and the memory battery that retains the calibration data in RAM measures 3V so no immediate worries there and as mentioned early it still seems to be pretty well calibrated when checked against my voltage and current calibration references so I'm pleased with my 2 purchases from the Ebay seller that mnementh discovered his side of the pond. Both of them would have cost me at least double the cost, and that includes the shipping and import duty, to purchase in the same condition over here.

[xrunner]

Good equipment that. 

Nice addition.

[bitseeker]

I'm about to rent office space so I have enough space for the gear I'm selling.

Can I join the club? 

Can you be a member of the club? A member?

I think you just became eligible to become the president & CEO.  .

Until Toploser decides to join up ! 

But Ice-Tea has TEA in his screen name!

[Specmaster]

Here's some photos of the 3 TDS210's doing a probe test, interesting thing is that each is set with the display to 45% contrast setting and each of the screens has a totally different colour to it?

I think I might have a problem here, I've gone from having no digital scopes, only analogues to having no analogues, 1 combi and 3 full on digital in just over a month 

Does anyone have any ideas as to why the screens vary so much?

[mtdoc]

Here are a few photos of the HP3468A

Nice catch!

In case you haven't seen it, here's a nice HP Journal article on the design of this meter from 1983.  Good read!.

[Cubdriver]

Here's some photos of the 3 TDS210's doing a probe test, interesting thing is that each is set with the display to 45% contrast setting and each of the screens has a totally different colour to it?

I think I might have a problem here, I've gone from having no digital scopes, only analogues to having no analogues, 1 combi and 3 full on digital in just over a month 

Does anyone have any ideas as to why the screens vary so much?

Are they that different when each is viewed head on?  Those older LCDs tend to have lousy off-axis viewing angles, and if you're relatively close taking the photo, then the center one is pretty much head on, the bottom one is being looked 'down' on, the the top viewed from below.

-Pat

[bd139]

The older LCDs age as well. The bottom one looks like my Korg Triton did until I replaced the screen.

[djos]

The older LCDs age as well. The bottom one looks like my Korg Triton did until I replaced the screen.

Plus the older LCD manufacturing process had a reasonable amount of variability in it - that's why every old device, with an active matrix style LCD, had a contrast adjustment.

[Specmaster]

Here's some photos of the 3 TDS210's doing a probe test, interesting thing is that each is set with the display to 45% contrast setting and each of the screens has a totally different colour to it?

I think I might have a problem here, I've gone from having no digital scopes, only analogues to having no analogues, 1 combi and 3 full on digital in just over a month 

Does anyone have any ideas as to why the screens vary so much?

Are they that different when each is viewed head on?  Those older LCDs tend to have lousy off-axis viewing angles, and if you're relatively close taking the photo, then the center one is pretty much head on, the bottom one is being looked 'down' on, the the top viewed from below.

-Pat

Here are the three scopes again, this time each one has been photographed on its own, in the same location and looking straight on to the screen from roughly the same position each time, The scope that was bottom on the group shot is the first one, the middle one is now the 2nd photo and the top one of the group is the third photo here.

[tautech]

Spec, from what I remember from the one I had the last screen pic looks most representative of what they should look like.
I'd be checking the backlight oscillator in case it's drifted off frequency like the TDS1k models can.
Just 'near field' probe them all to see what frequency they're running at.
If they're set up the same as 1k models using push/pull bipolars on the backlight primary with frequency controlled by a RC, check the C hasn't headed towards pF values.

[GregDunn]

I had a few moments to kill while in town for band practice today, so naturally (!) I wandered over to the local pawn shop.  I wasn't really intending to buy anything, but in the tools case was this old BK Precision meter model 5360.  Yeah, not the greatest meter ever, but it is a 50,000 count true RMS meter with a bar graph.  It was marked $10, but when I asked the associate to let me turn it on, it showed a display test and then some kind of error message on every mode (not a low battery indicator).  I couldn't quite read the message because, typically, the price sticker was on the display.     The guy scratched his head and said I could have it for $5.  I was pretty sure it couldn't have anything seriously wrong with it if the display test worked, so I forked over the money and left with it. 

In the parking lot, I carefully scraped off as much of the sticker as I could and switched the meter on again.  OK, go ahead and make fun of me; I spent a minute staring at it and trying to figure out what kind of code this was; then it snapped into focus and I laughed.  Easy fix.  After replacing FUSE2, it works great.

This is an IP67 rated meter, so access to the innards was a bit weird.  You're supposed to have a tool built into the bail stand to pop the protective covers off, but of course it was missing so I had to make do with a small screwdriver blade.  the battery and fuses are easily reachable without any further manipulation, and it did have good HRC fuses inside.  So, a win - even though the fuses are worth more than the meter cost.